Study Guide
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Acknowledgem,e nts
eo, er photograph: Mal'k lynden;ay, Lyndcrsay Digital, Trinidad
1
www.lyndersaydigirn1.com
fllustl'atlons: Oa\'ld Russell m usi:ration
Page malce-up: Panrck Media, Maidstone
TI1e author and the publisher would also like to thank the
foHowlng for permission to reproduce material:
t>14(t): from 'Geography in Place: Homework Copymasrers' by
Michael Raw and Sue Shaw, published byCo11ins Educational an
imprint of Harper Collins (1999); p14(b): adapted from Earth and
Man by B.J. Knapp; p22: from "Landslide Ha1.ard Geo Faccsheet' by
Simon Ross. pubHsht-<l by CuJTlCulum Press (2001). Reproduced
with permission: pSS: Nutrie1"ltS Cyc11ng in an Ecosystem
Copyright © 2009 Field Scudics Council; ppl 16•117: © \Vorld
1nde Press; p123: Dcmogra1,hk Transition Model frorn \""""·
coolgeography.co.uk Copyright © Robert Gamesby: p124: Adapted
from Demographic Statistics (various yearsl © 2012 Statistical
lnscltucc ofJamaica; pl28: Copi•1ight © United Nations 2012;
1>135(<): Copyright © 201 2. Go,•ernmenc of Barbados; pl 56: fro m
Philip's Cert.ificacc Atlas for the Caiibbean (6th Edition); p l 64:
from Caribbean 1.and!J' by J. MacPherson, published by J.,ongman an
linprinc of Pearson Education (1980); plOO: US Geological Survey.
Department of lncenorsjUSGS; pt 02: Copioighc © 2006 ilOML
All nghcs rcse,-vcd; pl03: Bureau of Meteorology Cop;oight 2012:
pl 07: Undsay, J. M.. Robertson, R.E.A.. Shepherd, J.B. s, Ali. S. (eds)
2005. Volcanic Ha1.anl At.las of the l.esscr Ancmes. Seismic Research
Unit, Tite Unlvc.rsicy of the \Vest Indies. Trinidad & Tobago, \•VJ:
p109: © National Oceanic: and Annosphe1ic AdministJ'at.ion/
Naclonal \\feather Seivkc (2004}.
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Introduction
1
1 Natural systems
1.23 Positive and negative impacts
of human activities in tropical
rainforest biomes
60
1.1 Theory of plate tectonics
2
1.24 Soil
64
1 .2 Types of plate bou ndary
4
1. 2 5 The hydrologica I cycle
66
6
1.26 Drainage system - f luvial
processes
68
1.27 River land forms
70
1.28 Coastal system - vvave
processes
76
1.29 Coastal landforms
80
1 30 Drainage patterns
86
1.3 The Caribbean and adjacent plate
boundaries
1 4 Occurrence and distribut ion of
earthquakes and volca noes
1. 5 Occurrence and distribut ion of
island arcs, ocea n trenches, fold
mountai ns and major fau lts
8
10
1.6 Int rusive and extrusive volcanic
feat ures
12
1.31 Coral reefs
88
1.7 The rock cycle
16
1.32 Mangrove \.Yetlands
92
1.8 Weatheri ng
18
1 9 Mass movement
22
1 33 Natural hazards and natural
d isasters
96
Unit 1 Practice exam questions
1.10 Limesto ne - formation,
characteristics and processes
24
1. 11 Limest o ne landforms
26
1. 12 Limesto ne landforms in the
Caribbean
1.1 3 Weather and climate in the
Caribbean
1. 14 Facto rs affecting weather and
climate
28
30
32
110
2 Human systems
2 1 Global population distribution
and density
112
2.2 Populat ion d istribution and
density in the Caribbean
116
2.3 Popu lation change
11 8
2.4 Populat ion struct ure
122
2.5 Popu lat ion growt h case
studies
124
2.6 Urbanisat ion in t he Caribbean
128
132
1.1 5 Equatorial and tropical
maritime climates
36
1. 16 Caribbean weather systems
38
1.1 7 Hurricanes
42
2.7 Problems of urbanisation in the
Caribbean: Kingston, Jamaica
1.1 8 Global warming - evidence
and causes
46
2.8 Cont rolling urbanisation
in the Caribbean
134
1.1 9 The effects of g lobal warming
48
2.9 International migration
in the Caribbean
136
138
140
1.20 Reducing t he impact of
global warming
50
1.21 Ecosystems
54
2.10 Economic sectors in the
Caribbean
1 22 Tropical rainforest biome
56
2 .11 Resources and their locations
2.1 2 Primary sector case study:
fishing
2. 13 Prima ry sector case study:
crude oil and natural gas in
Trinidad and Tobago
2. 14 Secondary sector case study:
food processing in the
Ca ribbean (CARICOf\/1)
144
146
148
2.15 Tertia ry sector case study:
tourism in the Carib bean
152
2.16 Tourism case studies:
Ja maica and Belize
156
2.1 7 Quaternary sector case study:
ICT industries and call centres
2. 18 Ag riculture in the Caribbean
~
\!.cy
2.1 9 Characteristics of com mercial
farm ing in Jamaica
2.20 Recent changes in Caribbean
commercial agriculture
168
2.21 Cha racteristics of commercial
sugar cane farming in the
Caribbean: Guyana
172
2.22 Challenges facing the
Caribbean economies
175
2.23 Environmental degradation in
the Ca ribbean as a result of
economic activities
Unit 2 Practice exam questions
158
160
164
Index
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178
182
184
This Study Gu ide has been developed exclusively with the Ca ribbean
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It has been prepared by a team wi th expertise in the CSEC• syllabus,
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Theory of plate tectonics
The structure of the Earth
LEARNING OUTCOMES
• Understand the structure o f
the Earth.
• Understand the theory of
plate tectonics and the causes
of plate movement.
If you slice an apple in half you will see three layers. The thin apple
skin is the outer layer. Beneath this is the thick fleshy layer and at the
centre is the apple core. The structure o f the Ear1h is a bit like this
(see Figure 1.1.1):
• Crust - the thin solid outer layer up to a thickness o f about 70 km.
Notice on Figure 1.1. 1 1hat there are l\,vo types of crust, oceanic
and continent al.
• Mantle - this is a very thick layer extendi ng to about 2,900 km. 11 is
mostly dense and solid, although there is a thin semi-liquid layer in
the upper mantle.
• Core - this can be d ivided into a liquid outer core and an iro n-rich
solid inner core. Temperatures here are extremely hot (5, 500°C).
The centre o f 1he Earth is 6,400 km below the surface.
-...-.i.:-··········-----··-···---·-··:--- - - - -- --......."''\..__
_ _ _ _O
_C_
EA_N_ _!
Plate - boundary
-.4
Plates
-++(huge
slabs
of the
crust)
LAND
Continental crust
·.
·-·-.
-
-
1--
Mantle
Crust
__________________,.
MANTLE
--t~ lnner core · -••
~ -outer core
Oceanic crust
...~.
Ocean ic crust (sima) - con tinuou s around the Earth's surface, mostly m ade of
basalt where silica (si) and magnesium (m a) are dom in an t
Continental crust (sial) - discontinuo us around the Earth and less d en se,
comp rising rocks such as granite where silica (si) and aluminium (al) dominate
Figure 1,1. 1
The structure of the Earth
The theory of plate tectonics
One of 1he fossils found in
Africa, Antarctica and India
that has been used to support
the idea of cont nental drift
is l,ystrosaurus, a p;g-sized
lizard t hat lived about 2 50
m lion years ago. l,ystrosaurus
was a herb vore tha t used its
horny beak to bite off pieces
of vegetation. ,twas extremely
abundant and was well adapted
to coping w "th the lo~v levels of
oxygen that ex,sted at the time.
It ·s, ho\,vever, now extinct.
_,
Unlike the skin of an apple the Earth's crust is not a continuous layer.
Instead it is broken into several large sectio ns called plates. Each plate
is about 100 km thick and is made up of the crust and the u pper part
of the ma ntle. The solid pla tes rest o n a semi-liqu id layer in the upper
mantle and this enables them to move in relation to each o ther.
Look at Figure 1.1.2. Notice the following features:
• The Earth is spli t into several large plates, such as the Pacific and
North American, and a number of much smaller plates, such as the
Cocos pla te and the Caribbean plate.
• The arrows indicate the direction of movement of the plates - on
average they move just a few centimetres each year, roug hly the
same speed as the gro1Nth o f you r fingernails!
• Earthquakes are concen trated at the edges (bou ndaries) of the
plates. This is w here pressure builds up and is then suddenly
released, resulting in an earthquake.
• There are four main types
of plate margins: divergen t,
convergent, collisio n and
transform .
•'
•'
.:•.
.,
..
,,-.·•..---..
~
,
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..
- . ..
110/lTrl f.1/EtCAS
>
What causes the plates
to move?
Deep within the Earth the
temperatures are extremely
hrgh. As the heat spreads
out and flows towards the
surface it forms a num ber of
large convection (heat) cells
(see Figu re 1.1.3). These hea t
flows, called convection
currents, rise from deep in
the mantle and move tO\'\lards
the surface. They then spread
belO\'\I the crustal plates, cool
and finally descend b.,ck down
into the mantle.
•
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Pate botJndaries and active zones o" the Earth's crust
What is t he evidence for plate tectonics?
Some 250 million years ago the continents o f the
world were joined together to form o ne enormous
continent called Pangaea. Since then the continents
have drifted apart to their current position . They are
still moving today as part of the world's giant plates.
The scientific evidence to support 'conf nental d rift'
includes:
Continental crust
~
)
Convecti~~ currents
in the Earth's mantle
'--.I
• Identical rocks in South America and West Africa.
• When two continents, such as South America and
A frica, are placed together they join up to form
a perfect fit, rather like 1\'Vo pieces of a jigsa~v
puzzle.
{
Figure 1. 1.3
\
(
-......
\___.,J
Convect·on currems in the Eanh's mant ,e
• Identical species of land-based fossils (crea tures t hat could not fly
or swim) have been found in continents that are today separated
by wide oceans.
• The rocks on the ocean floor (oceanic plate) become steadily older
the further they are from the middle of the ocean. As fresh volcanic
rocks form at a mid-oceanic ridge (divergent margrn) a conveyorlike movement pushes the rocks outwards from the centre.
During the 1960s and 1970s further scien tific evidence led to a
g reater u nderstandi ng of convection currents and of the mechanisms
involved ir1 plate tectonics. Pattems of earthquakes, volcanoes,
mountain ranges and deep ocear1 trenches provided evider1ce of the
precise location of the active plate boundaries.
Even today, scientists are still developing t heir understand ing o f
the theory of plate tectonics m the light o f recent earthquakes and
volcanic activity.
Oceanic crust
EXAM TIP
1"'- omey to start )'Yepa,i"'-0
foy 1::JOl-<Y e)(Al¾i....cttiov.1::10<-<
""'-"'st f,.Yst obtaiv. a cop!::J
of t"1e C¾l'l't vst s1::1ttab1-<s.
Rel¾el¾be, to J'YActise
c/yaw,"'-0 cliagya""'-S t"1at
!::! 0 " ""'-A tJ ...eecl to 1-<se to
it=we,- q"'estio= '"" t"1e
exa..,,._, ....atio""·
Types of plate
boundary
Divergent boundary
LEARNING OUTCOME
At a divergent pla te boundary (margin) two plates are moving
avvay from each other. This type of boundary is sometimes called a
constructive margin. This is because new crust is being formed,
effectively 'constructing' new plate.
• Understand the processes
and landforms at divergent,
convergent, co hsion and
transform pla te margins.
Look at Figure 1.2.1 . Notice the following features:
Mid-Atlantic Ridge
Islands such as Iceland
and the Azores
--~
AN
Atlantic Ocean
• A rising convection curren t is causing the
crust to crack, allowing molten rock (magma)
to pass through it on its way towards the
su rface.
• Some magma escapes to the surface as lava
erupted from underwater volcanoes. The
volcanoes at this boundary form a mou ntain
range called a mid-oceanic ridge. In places
this rises above the surface to form isla nds,
such as Iceland in the North Atlantic.
• Over millions of years, as new plate material
forms at the mid-oceanic ridge, the plates
extend outwards and diverge.
Convergent boundary
Flgure 1 .2. 1
Divergent plate marg·n: the mid-Atlantic Ridge
West
Peru-Chile deep-sea
trench (subduction zone)
East
Andes (fold
mountains)
I
..
ic
n
At a convergent (or destructive) plate
boundary tvvo plates are moving towa rds
one another. If one of the plates is made of
dense oceanic crust it w,11 dive down beneath
the other plate to form a subduction zone .
Here, immense heat melts and destroys the
su bducting plate.
Look at Figure 1.2.2. Notice the follovving
features:
• The Nazca plate to the west is diving beneath
the less dense continental crust that forms
part of the South American pla te.
• As the Nazca plate descends, friction along
the plate margin triggers earthquakes.
• The oceanic crust is melting and magma
is forcing its way to the surface to form
volcanoes.
• The crumpling of sea-floor sediments at this
boundary creates fold mountains which,
together \'Vith the ne\,vly formed volcanoes,
form the Andes.
Collision margin
When two plates of continental crust converge
they form a collision margin. Here, there is no
subduction since both are of the same density.
Instead the layers in the seabed bet\,veen them
crumple to form fold mountain ranges such as
the Himalayas (see Figure 1.2.3):
INOIAN PLATE
(continental crust)
Himalayas (including
moving north and east
Mount Everest)
EURASIAN PLATE
(continental crust)
stationary
• The enormous pressures and sudden
cracking of rocks often triggers powerful
earthquakes in these regions.
• There is no magma at these plate boundaries
O\<Ving to the lack of subduction. This means
that t here are no volcanoes.
Transform boundary
At a transform plate boundary l\,vo plates are
sliding alongside each other (see Figure 1.2.4a). f - - - - ~ - - - - - - - - - - - - - - ---'
The two plates may be moving in opposite
Figure 1.2.3 Coll:sion boundary: the H,malayas
directions or they may be moving at different
speeds in the same direction. There is no subduction taking place at
this ma rgin and no creation of magma. This explains w hy there are no
volcanoes along the San Andreas Fault (see Figure 1.2 .4b).
Earthquakes are very common at transform plate boundares. n
the great San Francisco earthquake of 1906 the San Andreas fau t
suddenly lurched by 6 m. Over t.50 persons were kil'ed by the
earthquake and much of the city was destroyed by the fires that
broke out.
.•·•• ...
a A transform plate margin
EXAM TIP
,
b The San Andreas Faull
o
100
km
·-.~ ~ ~ Francisco
,
The North American plate
.
• &
moves north-westwards by
··•!?<?
t cm a year but appears to
,l ,;,,-1?.:io
be moving south-eastwards
\, <>z.j •.f,;.s- In relation to the fasterPacttic plate '
•••• moving Pacific plate.
moving north- \
- •••
USA
westwards by
"}
•·,.
Transform plate margin,
where plates slide past
each other
PlateA
Plals B
6cm ayear
l_ ·... ·..
""b=
~
~
't,
N
·Los·..
ngeles ·•.
•
t
San"·,
Diego ··••
MEXICO
Figure
1,2.4
Trar.sform bosndary: the San Andreas Faalt, USA
The Caribbean and
adjacent plate boundaries
The Caribbean plate
LEARNING OUTCOME
Much of the Caribbean region lies on the Caribbean plate (see f igure
1.3.1). The bou ndaries of t he Car'bbean plate are extremely active as
it is being squeezed by converging plates o n either side. Notice the
following features:
• Understand the types o f
plate margins and landforms
associated with the Caribbean
plate.
• On the northern edge there ,s a t ransform boundary betv;een
the Ca ribbean plate and the North American plate. Sideways
movement occurring along 1his boundary has been responsible for
several major ea rthquakes, the most recent being the 2010 Haiti
earthquake, w hich killed over 230,000 persons.
• A t the western bou ndary, oceanic crust making up the Cocos plate
is subducting beneath the Caribbean plate, forming a zone of
volcanoes, earthquakes and fold mountains in Central America.
• The southern bou ndary is highly com plex, being part convergent
and part transform . Wh ile earthq uakes do occur here, it is not as
active as the other Caribbean plate boundaries.
0
km
500
N
NORT H AME RICAN
PLATE
Earthq ua~l · fol~ ~ulli~.Q - • .,.,,,
20foV
u.,--
~.
Fotq
-/to
1692
1907
Cayman Islands
Ridge
C A RIBBEAN
· 'l.o.-r,,' ,0
f863
1637 1824 197~6
~ "'Jt,
PL
TE
\
\
"~ fi,.2
193~
Q.
~
<,
--- "'~
"-...r--"'",..
,, SOUTH AMER ICA N
~<::P LAT E
, v;cq;i s
........_.,. •noe
~
<:,~
COCOS PLATE
~~
NAZCA
PLA TE
<Jf
r
i
.)
Flgure 1.3. 1
~
Plate boundanes n the Carib bean
<§'
"
l,•
<:-
~
•
Recently active
volcano
historic
0 Major
earthquake
Convergent plate
....._ boundarysubduction zone
rn'l1li1n:tShleld:
ancient. stable rock
_
Divergent plate
boundary
~ Tran~form plate
margin
~ Direction of plate
?-" movement
t
• To the east an active convergent
boundary exists betv,een the
South American plate and the
Ca ribbean plate. The subducting
South American plate is
responsible for the formation of
a chain of mostly volcanic islands
called the Lesser Antilles.
Formation of th e Lesser
Antilles volcanic arc
Most of the islands that form
the Lesser Antilles in the eastern
Caribbean are volcanic. They have
been formed at a convergent
plate bou ndary where the Sou th
American plate is subducting
benea th the Caribbean plate
(see Figu re 1.3.2).
Caribbean island arc
Milwaukeedeep-sea
trench (subduction zone)
MontserraJ
Quddeloupe
(La Soutnere)
PLATE
Dominica
Martinique
(Mt Pellle)
CARIBBEAN
SOUTH
AMERICAN
PLATE
St Lucia
Atlanllc
Ocean
Frlcbon lncrea$
heat causing Im
Jo rise to the
Eallti'ssurface
Figure 1.3.2 Formation of the eastern Caribbean island arc
Lines of 'Neakness develop in
the overly'ng continental crust
and magma rising from deep
underground reaches the surface to form a chain of volcanoes called
• • •
an isla nd arc. Ma ny of the volcanoes have erupted violently in the
past, such as fV1t Pelee on Martinique, which killed 30,000 persons
Kingston, Jamaica has been
in 1902. In recent years, Sou friere Hills on 1\/lon tserrat has been
struck by a number of powerful
erupting, leading to t he evacuation of many villagers from the south
earthquakes in the past In
of the island (see Figure 1.3.3).
1692 the old city of Port Royal,
south of Kingston harbour, \'Vas
destroyed by an earthquake and
2,000 persons were killed. More
recent y, n 1907, an earthquake
and fire killed over 800 persons.
EXAM TIP
w11e.,_ st1,<i;ltJ'""0
pl&ite tecta"'-•cs of tne
C&1ribbe&1"'-, ""'-&1~e &1""
effort to &1s.s.oei&1te speci-fi,e
vol ea "'-Oes wi.ti,i the
co"<"'-tries '"" wfli.en tJ.ie11
&ire fo"<~ .
Figure 1.3.3
The eruption of the Soufriere Hills volcano, Montserrat. n 1997
Occurrence and
distribution of earthquakes
and volcanoes
Earthquakes
LEARNING OUTCOME
• Understand the forma tion of
earthquakes, vo canoes and
fo d mountains.
An earthquake is a sudden violent shaking of the ground. Look at
Figu re 1.4.1 and notice the following features of an earthquake:
• The point \'Vithin the crust ~vhere an earthquake originates is called
the focus.
• The point on the grou nd surface immediately above the focus is
called the epicentre.
• The shockwaves that radiate ou t from the focus are seismic
waves. These are responsible for t he shaking that is felt on the
ground.
• An ea rthquake usually triggers movement along a crack called a
fault.
Each year there are thousands
of earthquakes across the world,
the majority of which are not
strong enough to be felt. When
earthquakes are plotted on a world
map they form an interesting
pattern (see Figu re 1.4. 2).
Epicentre
(shockwaves)
\
Flgure 1 .4.1
\
Notice that earthquakes tend to be
concentrated in clear linea r belts,
for example around the edges of
the Pacific Ocean and through the
middle of the Atlantic Ocean. This is
because the majority of earthquakes
are found at the plate boundaries
(see also Figure 1.3.1, page 6). Here
enormous pressures build up before
suddenly being released. It is this
sudden breaking or snapping, deep
within the Earth's crust, that creates
an ea rthquake.
Focus \ ~ Fault
Main featsres oi an earthquake
~tl•• tl
Ocean
AFRICA
,1
U
Volcanoes
Volcanoes are often tall conical
lndlJl'I
Oc: u n
USTR4~1
).
Flgure 1 .4.2
Major earthquakes zones around the world
landforms resulting from the
emission of lava, rocks, ash,
steam and poisonous gases such
as sulphur dioxide and chlorine.
f igure 1.4.3 shows the typical
features of a volcano. Notice ho,,v it
has become larger wit h every eruptio n and
how it is made o f alterna1e layers o f lava
and ash.
Ash cloud
Crater
.
'
Volcanoes do vary enormously in the·r
size and shape 01,i ng to the chemical
compositio n o f the magma (see page 13).
Look at Figure 1.4.4, w hich sho1,vs the
d istribution of volcanoes.
• As 1,vith eart hquakes t he majority
of volcanoes are found along plate
margins. It is here where there is molten
rock or magma to supply the volcanoes.
Alternating lava
and ash layers
• Can you identify the famous 'Ring of
Fire' stretch ing arou nd the edge of the
Pacific Ocean? This is 1,vhere the g reatest
concentration o f volcanoes lies.
Figure 1 .4.3 The typical features of a ...o!cano
• Notice that 1here are no volcanoes at
collision margi ns (such as the Himalayas)
or transform margins (such as 1he northern par1 o f the Caribbean
plate). This is because there is no supply of magma .
• Some isolated volcanoes exist a lo ng 1,vay from plate margins, such
as Mauna Loa on Hawaii. These locations are known as 'hot spots'
and are formed w here the crust is particularly weak, allowing the
underlying magma to break 1hrough along cracks and frac1ures.
~
Famous volcanoes
••• Volcanic activity
•
~~
ASIA
{}
•
i
I
Mayo'f
Mauna Loa•
PiAa 60
,.......
•• ,
I nd i an
• Ocea n
•
Agure 1.4.4
Pac ifi c
Ocea n
'
)(Ruapehu
I;)
Global distribution of volcanoes
•
('·
r,;
Cotopaxi
SOUT
,.., AMER CA
••••
•
•
.....•
Occurrence and
distribution of island
arcs, ocean trenches,
fold mountains and
major fau Its
LEARNING OUTCOME
• Understand t he occurrence
and d,stribution of island
arcs, ocean trenches, fold
moun ta·ns and major faults
Island arcs and ocean trenches
Island arcs and ocean trenches are landforms associated with
mid-oceanic convergen t plate margins. As one oceanic plate dives
benea th another a deep ocean t rench is formed. As the plate
subducts, melting occurs forming magma. This rises to the surface
to form volcanoes which eventually break the water surface to form
islands. A series of volcanoes along a length of the plate margin
creates an island arc (see Figure 1.5.1).
Lithosphere
Oceanic-oceanic convergence
Figure 1.5.1
Format on of island arcs
Figu re 1. 5.2 shows the distribution of island arcs and ocean trenches.
Notice that the majority are located around the Pacific 'Ring of f ire'.
1--Tiench
J
The highest fold mountain range
in the \'Vorld is the Himalayas
in Asia. It conta ns the top 1 5
peaks in the \,vorld, the highest
of 'Nhich is Mount Everest at
8,848 m above sea level. The
second highest moun tain 1s K2
at 8,611 m, although some have
suggested that this l"light in
fact be higher than Everest. The
debate con tinues!
"a
0
Japan
) Maliana
~~
Java
(j/J
"1/"
Tongan
Figure 1.5.2
Distribution of island arcs ar.d ocean trenches
I
Fold mount ains
At convergent and collision margins, ocean sediments and
continental crust can buckle and fold (bend) as a result of the
enormous pressures squeezing the rocks together. Huge fold
mountain ranges such as the Andes and Himalayas can form as
these folded rocks are thrust upwards by the converging plates
at these pla te margins (see Figure 1.5.3).
../
Hlm•!ay.u. /
"'"'
......
•
t
YQ\,mg fold mounu1!ni
Agure 1.5.3
Olsuibut,on of 'old mounta;ns
M ajor fa ults
The enormous pressures generated by tectonic activity ca n cause
extensive fracturing or faulting of the crust. Major faults are often
associated w,th transform plate margins where opposing forces tear
the rocks apart, for example the San Andreas Fault. Figure 1.5.4 shows
the distribution of these major faults.
The Mariana Trench is the world's
deepest trench, with a depth of
11,000 m. This distance belovv sea
level is equivalent to the cruising
alti tude above the ground of most
aeropla nes!
SUMMARY QUESTIONS
O'
90'E
180'
90~•/
1---1--~ I -K.t»,iwa!l---l-~---l--~l--l-~ - -I--I O'
1 Explain why ocean trenches
and island arcs occur
together in the ocea ns.
2 Describe the distribution of
fold mountains.
O'
3 Why do IT'ajor faults form at
tectonic plate margins?
Figure 1.5.4
t,.}ajor wor1d faults
90'E
180'
90~•/
Intrusive and extrusive
volcanic features
LEARNING OUTCOMES
• Understand the di fference
between intrusive and
extrus've foatures.
• Understand the features
associated with 1ntrus1ve and
extrus've activity.
Off the north coast of Grenada,
near Sauteurs, a dyke rose m
the sea overnigh t (during the
early part of the last century),
forming a natura breakwater
and produong a safe area ror
bathing on the normally ro.igh
north coast.
Lava flow
Laccol~h
Wh at is the difference between intrusive and
extru sive featu res?
Magma is a mixtu re of molten rock, gases and liquids and is formed
in the mantle. As it passes through the crust most of it cools before it
reaches the surface. This cooling and solidifying of magma in cracks
and joints forms intrusive volcanic reatures.
If magma reaches the Earth's surface, it will form extrusive volcanic
features, the most obvious one being a volcano. So, try to remember
that in trusive means 'in' the crust and extrusive means on the surface.
Types of intrusive volcanic fea tures
Look at Figure 1.6. 1. Notice that there are several types of intrusive
volcanic features:
• Batholith - this is an enormous mass of igneous rock, often
hundreds of kilometres across, which forms when magma cools
deep inside the crust. In the Caribbean the best-knO\<Vn example is
the Tobago bathohth, which extends from west to east and is about
half the size of the island .
• Dyke - this is formed when magma passes
Volcano
through cracks or Joints t hat cut across beds
(layers) of rock. Dykes often occur in groups
called swarms, for example at the southern
tip of St Lucia.
• Sill - \<Vhen magma forces its way
between beds of rock it may solidify to
form a sill.
• Laccolith - this is rather like a blister t hat
has been formed between two layers of
sedimentary rock, causing overlying rocks to
arch upwards.
Sill
Flgure 1 .6. 1
Volcanic features
EXAM TIP
W"1e"': Al,\,Swey["'-0
"("<tsho""5 AboL<t voLc.i"'-Des
1::1°"< s"1oL<Lel be ti bLe
to el YAW A""ci LA bet t"1e
elisti..,.,cti.ve fe.rt"<Yes of the
t1::1pe of voLc.i""o 1::fO"< AYe
ci esc ..-i. b, ""0·
Types of extru sive vol canic
features
Look again at Figure 1.6.1 and notice that some of the volcanic
features have been formed on the surface. These are extrusive
volcanic features. They are formed when magma breaks through the
crust to reach the surface. Once on the surface, the magma loses its
gases. The liquid remaining is ca lled lava.
• Volcano - most volcanoes are formed over many thousands of
years by a series of eruptions through a cen tral vent or opening .
With each successive eruption the volcano grows a little higher.
It is possible to identify t\<VO broad types of volcano: shield and
composite . Figure 1.6.2 describes the differences between them.
Ash layer
Conelet
Composite volcano
Composite
• Steep, conical volcano
Lava layer
• Typically formed at destructive
plate margins
Lava flow
• Acidic magma (lava)
~ dd ;;:;--Vent
• Explos·ve eruptio ns
Shield
Shield volcano
• Flat and broad volcano
About 110km
• Typically formed at constructive
margins
Layers of lava
• Bas•c magma (lava)
9,000m
• Gentle eruptio ns
About 400 km
Fig ure 1.6.2
Extrusive volcanic features
Occasionally a violent eruption may cause a volcano to blow its top
off leaving behi nd a huge crater called a calder a (see Figure 1.6.3) .
If the underlying magma chamber has been emptied by the
eruption, the surface may collapse to form a deep basin, w hich
may in time contain a lake.
• Lava plateau - ·n some places, for example on Iceland o n the
Mid-Atlantic Ridge, fluid (basic) lava spreads ou t from linear
cracks to cover large areas o f the ground surface. These eruptions
are called fissure eruptions (fissure= crack). One of the most
extensive lava plateaus in the vvorld is the Decca n Plateau in India,
which covers nearly 650,000km' (for comparison, the size of
Jamaica is 10,991 km'!) .
Types of lava
It is possible to identify two broad types of lava (and magma):
• • •
•
The Yellowstone Caldera in
Wyoming, USA measures
55 x 72 km' 1n size and Is
the site of one of the ~vorld's
'supervolcanoes'. The caldera
formed when t he underly ng
magma chamber elT'pt'ed
during an eruption and the
surface co.,apsed to form a huge
basin. Yellowstone last erup1ed
some 17,000 years ago.
• Basic lava - this is rich in iron and mag nesium but has a low
silica content. It is very hot, often reaching temperatures of
1,000-1,200°C. It is very 'runny' (fluid) and will flovv on the
surface for considera ble distances to form
broad, gently sloping cones. When it cools it
fo rms an igneous rock called basalt. Basic lava is
associated w ith constructive plate margins and
wi th the formation o f shield volcanoes.
• Acid lava - this low-temperature magma
(800-1,000°C) is rich in silica, v,hich makes
it more viscous (thicker, less fl uid) than basic
lava. It does not flow far on the su rface befo re
it solidifies and results in high steep cones.
Acid lava ·s associated w,th the formation
of composite volcanoes at destruct ive plate
margins. Eruptions tend to be more violent than
at basic (shield) volcanoes.
Figure 1.6.3
The water-lilied Qui,otoa caldera in Ch le
LEARNING OUTCOME
• Understand intrusive and
extrus've vo canic andscapes.
Intrusive volcanic landscapes
In trusive volcanic features are often formed many hundreds of
metres belo\<V ground. It is o nly w hen the overlying rocks have been
removed by erosion that they become exposed o n the surface to form
landscape fea tures.
In trusive igneous rocks are usually tough and resistant to erosion.
When exposed at the surface they are of1en eroded more slO\<Vly t han
the surrounding rocks and form ridges or upland areas.
• Vast batholi ths may be exposed to form uplands, such as Dartmoor
and Bodmin IV1oor in south•\<Vest England (see Figu re 1.6 .4).
rs•es ol
Scilly
Danmoor
Bodmn
I
A
~1-0or
Land's
End
B
N
Dartmoor
+
Bodmin Moor
Newquay
s'esof
Sci':y
•
•Plymouth
Land's End
Figure 1.6.4
0
20 km
Exposed granite batholith in south-west England
• Sills and dykes are much smaller than batholiths and, when exposed,
tend to form dips or ridges in the landscape (see Figure 1.6.5).
EXAM TIP
Wne"': a"'-!:werii,,,g
questLO"'-S a bout volcci ""'c
features it i.s ""'-)'Orta ""t
to cl.iffere~icite betwee"" ci
feciture a""ol ci Lei""°'foYI¾.
For ex.a"'-ple, a sill ei""°' a
d!jk.e cire features wl-iile
a plateau a.,.ol Cl volca.,,,,c
"'-_OUi,\.tCIL"'- Cl Yt la "'-ol fo f'l%5 .
SLLls al'\.ol o11::1ius forl¾
Lei""°'f0 rl¾s sucl-i as Yiolges
a ""°' es caYJ' "'-t ....ts .
Figure 1.6.5
Landscape features formed by sil sand dykes
Extrusive volcanic landscapes
Extrusive volcanic features create immediate landscapes, either in the
form of spectacular volcanoes o r as extensive lava plateaus. On the
surface t hese landforms are affected by weathering processes, such
as oxidation (volcanic rocks are often rich in iron) and freeze-thaw.
Rivers and glaciers will sculpt these landscapes, forming valleys and
gorges.
• Lava plateaus tend to form relatively flat landscapes. Rivers will
carve broad valleys and the channels t hemselves \'Viii often be
meandering (see Figure 1.6.6).
1
3
Rlvervaney cuts
through tava
Into rocl<S
below
Pipe throughwhich
lava 11ows
magma reaches thesu~ace
Figure 1.6.6
Formation and erosion of a lava plateau
• Steep-sided volcanoes will be subj ected to severe river erosion as
t he steep gradient leads to fast-flo\,ving rivers. Deep gullies and
valleys \'Vi I radiate ou t from the centre of the volcano and large
deposi ts of sediment (alluvial fans) will spread out at its base. Over
a very long period of time all that \,viii be left is the volcanic plug in
the centre of the volcano (see f igure 1.6.8) .
• • •
2
1
Magma
solidffles in vent
Volcano
Agure 1.6.8
A vo canic plug
Volcanic plug
Sides of volcano
gradually worn
away by
weathering
,,:,and erosion,.;::::'½
I
Pett Piton is one of several
volcanic plugs on the island of
St Lucia. Petit P'ton itself rises
spectacularly straight out of the
sea to reach a heigh t of 743 m.
It 1s a UNESCO World Heritage
Si te and forms a chal'enging
ct:mb for experienced
mountaineers.
The rock cycle
LEARNING OUTCOME
• Understand the rock
cycle and forrration of
igneous, sedimentary and
metamorphic rocks.
The rock cycle
The rocks that make up the Ea rth's crust are in a constant state of
change d ue to processes such as weathering, erosion, transportation
and deposit ion . It is this recycling o f the Earth' s rocks that is termed
the rock cycle (see Figure 1.7. 1).
Fi ure 1.7 .1
The rock cycle
Figu re 1.7.1 shows that the Earth's crust is made o f three types of
rock:
• Igneous rocks - these are rocks that have formed from the
cooling of magma (ignis is the Latin word for ' fire') either belov.r
the surface (intrus ve) o r above the surface (extrusive) . Igneous
rocks are crystalli ne and are usually hard and resista nt to erosion.
Examples include granite (in trusive) and basalt (extrusive) .
• Sedimentary rocks - these rocks form from t he accumu lation of
sediment, most commonly in the oceans. They include sandstones,
shales and limestones and t hey often contain sig ns of life (fossils).
Sedimentary rocks usually form layers or beds. They tend to be
\'\leaker than igneous rocks and are more easily eroded.
Figure 1.7.2
Limestone rock on
Bathsheba oeach In
Barbados
• Metamorphic rocks - these rocks have undergone change as a
resu lt of intense heat or pressure. They are extremely strong and
resistant to erosio n, forming moun tain ranges in many parts of the
\,vorld. Examples o f metamorphic rocks include slate (formed from
shale and used as roofing), quartzite (from sandstone) and marble
(from Iimestone).
There are examples of all three types of rock in the Caribbean, with
the sed imentary rock limestone being o ne of t he most common
(see Figu re 1. 7.2).
<l<loleil ""'8"•~~:."~
n,e w igneous ,
7
Ma•'"'•• f
\
River to the sen
"
'1elted rocks
Sediment
•
•
form magma \
• •
L1fT'estone 1s a very useful rock. It
is used to manufacture cemen t
and to spread on fields to
make soi.s less acidic. Crushed
limestone can act as a filter
in power stations to remove
harmfu l gases. Next time you
brush your teeth, be aware that
the toothpaste may we I contain
some imestone as it acts as an
abras vel
St:dirnent fonn~
sedimen1arv rQC-~
J
when com,;res~I
or heated
l\·letamorphk "-._
rocks
_________.....
Intense heat or pressure
1urns scdirnenrary rocki; 10
metamorphic rod~
Figure 1.7.3
Sedimentary roclcs
Sequence of movement wth:n :rhe rock cycle
As Figu re 1.7.3 shows, rocks are constantly 'o n the move' vvi thi n the
rock cycle.
For example, ig neous rocks at ground surface w il be \'\leathered and
eroded by the wind and rain. The broken pieces o f rock will then be
transported by rivers or glaciers to be deposi ted in the sea. The layers
of sediment that build up on the seabed will then be compressed and
heated to form sedimentary rocks . These rocks may then be subjected
to intense heat or pressu re causing them to turn into metamorphic
rocks. If the rocks are melted, magma will be formed \'Vhich, when
cooled, wil l form new igneous rock- and so the cycle is complete!
SUMMARY QUESTION
Ora\'\/ a flow diagram to show ho1N a grain of sand n the
mountains can eventually be turned into the metamorphic rock
quartzite.
Figure 1.7.4
Granite rocks on a beach
Weathering
LEARNING OUTCOMES
• Understand the meaning of
weathering.
• Understand that there are
three types of weathering:
physical, chemical and b otic
(b1olog1cal).
• Understand the processes of
physical weathering.
Weathering is the gradua l breakdown or decay of rocks in their
original place (in si tu) at or close to the ground surface. As the name
suggests it usually results from the weather such as rainfall and
changes in temperature.
When rocks have been weakened they are easily picked up and
carried avvay by wind, water (rivers and the sea) and ice (glaciers).
This is called erosion. The combination of wea thering and erosion m
lowering a landscape is called denu dation .
It is possible to identify t hree types of wea thering:
1 Physical weathering . This involves rocks breaking apart but
vvithout any chem ical change taking place.
2 Chemical weathering. This is where a chemical change causes
rocks to dissolve or decay.
EXAM TIP
Lear.,, tne ~ei:J ten¾s a.,,i;1
be c&1ref1,1.L "'-Ot to co"'-f1A.Se
'ti:Jpts' of weatneril'\..C\
(f111;1s•c&1,L, cvie""-,c&IL~&I .,,&I
b,ot.c) w,tn 'processes'
of ':'e&rtner,...g (e.g. f rost
/;IChOI'\.) ,
3 Biotic (biological) weat hering . This involves living organisms,
such as plants and animals (for example rabbits), or acids from
rotting vegeta tion.
Several factors influence the type of weathering that occurs at any
one place, such as the climate, the type of rock and the amount and
type of vegetation. Often more than one type of weathering occurs
at any one place.
Physical weathering
Day
11 \
I• \
~
Water collects in
, crackS in rock
.
• (• Night
I \
'
Water freezes toform Ice
ExPansion causes stresses
• and cracks areenlarged
/ • (• Repe_ated
freezing
and tllawi!lll
I '
I\
I
Frost acti on
Frost action, sometimes called freeze-thaw or frost shattering, is one
of the most effective processes of physical weathering, although it
is not very w;despread 'n the Caribbea n. Look at Figure 1.8.1 to see
ho,N it operates.
In order for frost action to be effective, there needs to be:
\j
I,,- ,-
You need to understand three types of physical weathering: frost
action, pressure release and temperature changes.
-.V, offRockandfragment
breaks
collects as
,·. \ scree at the foot of the
rockface
Figure 1.8. 1
I The process of freeze•
tha•N vv'eathenng
• plenty of rain fall
• frequently fluctuating temperatures above and below freezing
• rocks vvith cracks or holes.
This explains \,vhy frost action is severe 1n sub-Arctic regions, such as
northern Canada, and mou ntains, such as the Rockies and the Andes.
Much of the Caribbean is too wa rm for frost action to occur and, at
the other extreme, Anta rctica is too cold!
When frost action affects rocks on an exposed cliff or mountainside,
angular rock fragments collect at the base to form scree. The jagged
rock fragments may be ca rried by rivers and ice, where they become
important 'tools' of erosion.
• •
Temperatures 1n hot deserts can
reach over 45°C during the day
and plummet below freezing
at nigh1. Th:s is because the
lack of cloud cover maximises
daytime temperatures but al lows
heat to escape at night. The
highest recorded tempera ture
\,vas 56. 7°C ·n Death Valley,
California, USA, in 1913.
Figure 1.8.2
Crack caused by pressure release
Pressure release
Rocks deep underg round are compressed by the
immense weight of the rocks on top of them.
When these overlying rocks are eroded, the
pressure is released and the rocks belo,N expand
upvvards, rather as if they were breathing outf
This is pressure release.
During the day
Outer layer expands
during lhe day ...
Pressure release causes cracks to form parallel to
the surface (see Figure 1.8.2).
Pressure release is responsible for causing largescale rounded landforms, such as Half Dome in
Yosemite National Park, USA. In the Caribbean,
pressure release has been partly responsible for
some of the granite landforms on Tobago.
Exfoliation
Extreme changes in temperature, such as
those experienced in hot deserts, can also
lead to exfoliation in rocks. High terrperatures
can cause the ou ter layer of rocks to expa nd
whereas very cold temperatures lead to
contraction. Regular tempera ture fluctuations
will weaken the outer skin, eventually causing ,t
to flake a\,vay (see Figure 1.8.3).
Some rocks, such as granite, are made up of
different minerals. These minerals expand and
contract at different rates causing the rock to
break apart into granules. This is cal led gra nular
disintegra tion.
Al night
and contracts
al nJg'11
Alter a period al lime
~ - - -Next layet now open
IO diurnal neallng and
cooling
Pieces of outer
layer broken off
-
Figure 1.8.3
The pre<ess of exfoliation
LEARNING OUTCOME
• Understand the processes
of chem·ca and biotic
(blolog1cal) ,,veathering.
• •
Carbon diox'de is more soluble
in water at lo•N temperatures.
This means that 1he process of
carbonation Is more effective
in cold clill"ates than warm,
tropical clima tes.
Chemical weathering
Chemical \,veathering involves chemical changes taking place within
a rock. It most commonly occurs when rocks are in contact \,vith
water. This explains ,,vhy it is most active in tropical environments
that experience high rainfall totals. Chemical weathering may cause
minerals to be dissolved or cause them to turn into weak and easily
eroded clay.
Carbonation
Carbonation is a process of chemical \,veathering that affects
calcareous (calcite-rich) rocks such as limestone. Limestone is a
common rock in t he Caribbean. Look at Figu re 1.8. 4 to see how
carbonation operates.
/
/
/
/
/
/
/
/
Rainwater picks up carbon dioxide CO ) from the air
6
/
/ ~
/
/
6J/
/
/ \5)
/
/
~
~
Rainwater becomes a weak carbonic acid
/
/
///
/
/
/ / / / /l / /,, / / / /
/
/
/
/
/
,·
, C ';)
/
Acidic rainwater reacts with calcium carbonate (CaCo,) to form calcium
hydrogencarbonate (!2._rmerly called calcium bicarbonate): which then dissolves
,
,
,
/
/
/
/ :)
/
/
- ~-- - •
n some parts of the world,
for example n Cheshire, UK,
salt deposits underground are
del•bera tely d1sso'ved using
pumped water. Once dissolved,
the salty water (called br ne) is
pumped back to the surface
and the water is evaporated to
leave behind the solid salt. Sa,t 1s
commonly used in the chemical
industry.
Fi ure 1.8.4
/
LIMESTONE or CHALK (CaCoJ
The process of carbonation
Carbonation is responsible for a number of landforms associated ,,vith
limestone (karst) scenery, such as limestone pavements and swallow
holes (see pages 26-7).
Hydrolysis
Hydrolysis involves chemical change due to reaction ,,vith •Nater.
When mildly acidic rainwa ter falls on grani te, a common igneous
rock, the mineral feldspar reacts and turns into a ,,vhite clay called
Figure 1.8.5
Gran seweathered by hydrolysis
kaolin (or china clay). This process weakens the granite,
causing it to disinteg ra1e (see Figure 1.8.5).
Biological weathering
Biological weathering results from the physical and
chemica l effects of living organisms. One of the most
effective processes involves the growth of tree roots,
which can prise apart joints in rocks (see Figure 1.8.6).
Tree roots are amazingly s1rong and can penetrate
several metres into underlying bedrock. INater may flow
along these roots causing chemical weathering too.
Joints in rock
Animals such as earthworms, coneys, rabbits and
insects burrow into soil and weak rocks. This not only
further vveakens the rock bu1 also ena bles vvater to
soak into the ground where it may carry out chemical
weathering .
Rotting vegetation \,viii increase the acidity of rainwater
as i1 collects on the grou nd and then soaks in1o 1he
soil and rock. By increasing its acid ity, 1he water
becomes more effective in V'tea thering the bedrock.
Rock
Bedding planes where
roots have grown
Figure 1.8.6
SUMMARY QUESTIONS
Look at Figure 1.8.5.
1 What is the evidence that the rock is being
affected by processes of chem1ca weathering?
2 Do you th nk b ological weathering is happening?
3 Do you think frost action is l"kely to affect the
rocks here?
Bedding
plane
Tree root action
Join! where
rootnas grown
Mass movement
Mass movement is the downhill movement of soil and rock
LEARNING OUTCOME
under the influence of gravity. l andslides are an example of a fast
movement whereas soil creep is an example of a slow movement.
• Understand the processes
associa ted with mass
movement.
-
Land slides
Pi'o!onged ralnlall
Tti1s wilt :;aturnte the soil
and encourage mov~men1
io.--,,. -
D
D
Human !actor
Physical lac1or
Buildings
l11Crease weight on slope and
add 10 downward pull ol gra\'lty
Removal 01 vegerallon
Roclflype
Roors bind lhesoil 1oge1her.
Vege1a1lon uses up some of
Weai. weaitte,ed male·li
ot sfiatteted ,ock Is ,ro,e
the soil moisture
hkely lo move \hansolid
..6...
ed..
•o...
ck....,::--"""":-'' Permeablllly
vfate· flgl'llng on sorlace
cl lmpe•meabfe 1aye1
Bed,ock
SolidbedrQc< below lveak <oa1er1a1. !he
1unctioa lo•frs lMlikely slide pla~e
Fi
ure 1.9.1
-=-~~
Factors contribut;ng to the
Destruction caused by
landslides after heavy ran
in Brazil
Ercavallon
Unde•cul1ing ol slOpe
Increases lnstabillry
A landsl id e is a sudden downslope
movement of part of a hillside. Landsl ides
can involve large blocks of rock sliding
downhill very rapidly. Alternatively,
saturated soil and rock can 'flow' downhill
and travel some distance. These are
mudflows.
Several factors make a slope unstable and
likely to collapse (see Figure 1.9.1). Notice
that there are both physical and human
factors.
There is usually a sudden event that
triggers a landslide on an unstable slope,
such as heavy rain, an earthquake or a
volcanic eruption, as follows:
• Heavy rain. Water lubricates and adds
\<Veight to a slope. Water pressure often
increases within the slope and this can
trigger a landslide. Extreme rainfall events,
ands!ide hazard
such as hurricanes in the Caribbean or
monsoon rains in India. frequently trigger
landslides and mud flows. In 1999, torrential rain in Caracas,
Venezuela triggered mudflows that killed over 30,000 persons and
left over 200,000 persons homeless. In 2010, heavy rain triggered
a massive landslide in the Brazilian city of Niler6i, close to Rio de
Janeiro. A \<Vall of mud and rock slammed into an area of slum
housing causing about 200 deaths.
• Ea rthquakes. Sudden ground shaking may cause an unstab1e
slope to collapse. In 1970, a powerful earthquake caused the
partial collapse of Huascaran mou n1ain in Peru. The avalanche of
rock and ice, travelling at speeds in excess of 300km/h destroyed
1he town of Yungay in the Rio Sa nta Valley and killed some 20,000
persons.
• Volcanic eruptions. Volcanic eruptions are extremely violent
events. Melting ice and snow can combine ~vith ash to form a
devastatmg mudflo\<V called a lahar. In 1985, the volcano Nevado
del Ruiz in Colombia erupted. An immense and fast-moving wall
of mud slammed into the town of Armero, killing an estima ted
22,000 persons.
' CASE STUDY
Lands ides in the Caribbean
Mameyes, Puerto Rico (1985)
Following a period of torren tia l rainfa I associated with Tropical Storm Isabel, a huge sla b of hills•de
collapsed in Mameyes, part of the sprawling city of Ponce. The landslide destroyed about 120 houses and
killed over 100 persons, possibly as ma ny as 300. This is t he grea test number of casualties from a single
landslide event in the Ca ribbean. Scientists believe that sewage discha rged directly into t he ground,
together with a leaking pipe, may have contributed to the disaster.
Tob ago (2004)
In November 2004, t1No ind ividuals were killed and five wounded in a landslide that followed six hours of
torrential rain. The clearing and bu rning of land on hillsides has been a contributory factor in landslides
on t he island.
• M ining. Coal mining can occasionally trigger landslides. In 1903,
76 persons were killed \o.,hen a 30 million cu bic metre chunk of
Turtle Mountain collapsed on the small mining settlement of Frank
in Alberta, Canada. In 1966, one of the UK's worst natural disasters
involved the col lapse of a coal spoil (waste) tip at Aberfan in Wales:
116 children and 5 teachers died when the landslide smashed into
the primary school.
• •
The biggest landslide ever
recorded occurred ,n 1980
\o.,hen a huge section of the
north face of Mt St Helens
volcano collapsed unleash·ng a
devastat ng volcanic eruption.
Soil creep
Soil creep is an extremely slow downhill movement of soil. While it is
too slow to be able to see it ha ppening, you can see evidence of the
process on hillsides (see Figure 1.9.3).
EXAM TIP
Wet soil is more likely to move downhill, which is why the process
is qui te active during the wet season in tropical climates, such as
the Caribbean . Movement often involves the alternate expa nsion
and contraction associated wi th wetting and drying or freezing and
thawing . This process is called heave.
Telegraph pole tilted
Tension gashes
in road
Base of tree turned downslope
Expansion (wetting/
freezing)
_,.._
1---1-Contraction
(drylng/
thawing)
Sol particle
moves downhill
ThlnJer soil at
top of slope Thicker soil at
bottom of slope Soil plied up behind wall
forcing It to bulge and break
Figure 1.9.3
Causes and effects of soil creep
Limestone - formation,
characteristics and
processes
LEARNING OUTCOME
• Understand the formation of
limestone, ts characterist cs
and associated processes.
Formation
Limestone is one of the world's most common types of rock. It
is a sedimentary rock that forms in shallow seas under tropical
conditions. In fact, new limestone is being formed at the present time
m calm waters close to the Bahamas and in coral reefs throughou t
the Caribbean .
• Limestone is very rich in the chemical calcium carbonate (CaC0 3)
and is known as a ca lcareous rock.
• Most limestone is formed from t he remains of organic matter, such
as shells, corals and plants. This accounts for its high concen tration
of calcium carbonate and explains vvhy limestone is often full o f
interesting foss•ls (see f igure 1.10. 1).
There are several different types of limestone:
• Carboniferous limestone. This grey limestone forms upla nd
areas in the UK, such as the Penn ine Hills. It was formed some
340 million years ago in tropical seas that vvere rich in shellfish and
corals.
Figure 1.1o.1 A pair of fossi ised shrimp
• Jurassic limestone. This type of limestone is found throughou t
the Caribbean. Formed 120-1 50 million years ago it is widespread
in Cuba, Jamaica and Puerto Rico.
• Oolitic limestone. Ooliths are tiny balls of limestone, usual ly
smaller than a pea. When a small fragment of shell or rock is rolled
on the seabed, calcium carbonate dissolved in the \'Valer may be
precipitated to form limestone. Over time, as more and more
limestone forms on t he shell or rock fragment, it grows in size to
form an oolith. The ooliths eventually form grea t thicknesses and
become compressed to form oolitic limestone. In the Caribbean,
oolitic limestone can be found on the Turks and Caicos Islands. It is
currently being formed on the Bahamas Platform .
• Chalk. Chalk is a \'Vhite type o f limestone that \'Vas formed ·n the
Cretaceous geological period (145-65 million years ago). It is very
rich in calcium carbonate (97 per cen t) and is commonly found in
the UK. Have you heard of the 'whi te cliffs of Dover'?
Characteristics of limestone
Limestone has a number of impor tant characteristics that affect
the processes acting on it and the landforms it produces. These are
described in Figure 1.10.2.
Processes
The physical and chemical characteristics of limestone (see Figure
1. 10.2) affec1 the types of processes that opera te on it.
Limestone
Limestone
Limestone
Physic ally, Is pervious as
is also
is made of
Vertical limestone water percolates
permeable as
calcium
joints is a tough
through joints
water can filter
carbonate
rock
and along
through the
and is vulnerable
bedding planes pores in the rock to carbonation
I_
_J -
_1 - I
I
Figure 1.10.2 Characteristics of I mestone
• Carbonation . This type of chemical 1Neathering is very effective
because limestone is so rich in calcium carbona te. Rainwa ter that
has absorbed carbon dioxide from the air becomes mildly acidic
(carbonic acid}. This reacts with the calcium carbonate and causes it
to slowly dissolve (see page 20). Carbon dioxide is more soluble in
colder cond itions. This explains w hy carbonation in the Caribbean
is more likely to be effective during cooler nights rather than during
t he day. Chem ical weathering is responsible for producing the
extraordinary jagged limestone ou tcrop at Hell on Grand Cayman
(see Figure 1.10 .3) .
The formula for carbonation is:
caco,
Calcium
carbonate
+
co,
Carbon
dioxide
+
H10
\/1/ater
->
Ca(HC0,) 2
Calcium hydrogencarbonate
(calcium bicarbona1e)
• Frost action. This is common in temperate regions
of the world . Water can collect m joints and cracks
in the limestone. ~Vhen it freezes, it expands,
forcing the crack apar t. Repeated cycles o f freezing
and thawing will even tually cause fragments o f rock
to break away (see Figure 1 .8. 1, page 18).
• Mass movement. Occasionally blocks of limestone
may become detached resulting in landslides.
Frost actio n may be responsible for rockfalls, \"Jhen
individual rock fragments fall from cliffs.
• River erosion. Limestone is pervious and water
will readily flow through the jo ints and along
bedding planes, sometimes forming fast- flowing
underground rivers. These rivers are capable o f
carrymg out intensive erosion to form features such
as caverns. On the surface, ho,"Jever, there will be
few rivers. This lack of surface river erosio n partly
explains \"Jhy limestone tends to form upland areas.
Limestone landforms
Limestone landscapes
LEARNING OUTCOMES
• Understand the characteristics
of imestone ,andscapes,
• Understand the forma tion of
surface landforms (limestone
pavements, gorges and dry
val eys, and swallow holes).
• Understand the forma tion
of Jnderground and forms
(caverns and caves, stalactites,
sta agm tes and pi llars).
Limestone is a physically tough and resistant rock that usually forms
upland areas. Its permeability resul ts in few surface rivers unless the
water table (the upper level of u nderground water) is particularly high .
Chemical \'Veathering causes it to dissolve, leaving behind very little
rock material to form a soil. This explains why limestone areas are
often bare and rocky, w ith few trees.
Look at Figure 1.11.1. It shows some of the landforms 1hat can be found
in limestone areas. Notice that some of the features are underground .
Surface landforms
Limestone pavements
• Limestone pavements are large and generally fla t, exposed areas
of limestone.
• The joints are often enlarged by weathering to form deep cracks
called grykes. The blocks of rock between the grykes are called
dints.
• Limestone pavements are very common in the Pennines in the UK.
This is because, in the past, advancing glaciers stripped away the
pre-existing soil and vegetation, exposing the limestone to weathering .
They are also present around St Lucy and Barbados, and on Antigua .
Gorges and dry valleys
• In the past, when water tables were higher or when limestone was
frozen during an ice age (for example in the UK some 12,000 years
ago), \'Vater would have been able to flo,N over the surface of the
limestone.
Limestonepavement wl:h clin'.s and g,vkes
Impermeable rock
1Joints l-~
□ ry valley
Permeabte
carboniferous
limestone
gence (sprlnO)
Figure 1.11 ,1
limestone .:eatures
• Valleys and steep-sided gorges were eroded by fast-flov,ing rivers
or glacial meltwater (Fern Gully is an example of a limestone gorge
in Jamaica).
• Since \'Valer tables have fallen, these valleys and gorges have
become 'dry'.
Swallow holes and surface depressions
• A swallow hole or s•nk is an enlarged joint down which water
plunges as ·1 flo\,vs off an impermeable rock onto limestone.
• Erosion and \'\leathering processes often lead to the swallov, hole
becoming wide enough for potholers to enter underground cave
systems (see Figu re 1.1 1.2).
• Large surface depressions cal led dolines are formed by extensive
chemical \,veathering or the collapse of limestone. These can be up
to 30 m in diameter.
Underground landforms
Caverns and caves
• As water flows along joints and bedding planes it is often con fined
in to small spaces. This increases water pressure and can enable
the \'Valer to be a powerful erosive force, carving passages and
enlarging them to form underground caverns (see Figure 1.1 2.4,
page 29). In the formation of caverns, processes of carbonation
and solution also aid in enlarging joints.
• When the water eventually reappears at the surface as a
resurgence (spring) it often forms a cave. (A cave has an opening
to the outside whereas a cavern is totally enclosed underground.)
An example of this is the One Eye river near Balaclava in Jamaica.
• •
Bermuda has recorded over 150
limestone caves, many of which
are no\,v submerged below the
sea. Bermuda's longest cave,
the Green Bay Cave Systerr,
is totally submerged and
contains over 2 km of explored
passageways. They contain an
amazing range of cave-adapted
species of invertebra tes, some
of which are extremely rare. The
fact that many of t he caves and
caverns are now below sea level
is evidence that sea levels have
risen over the ast 10,000 years,
since the features were first
formed .
EXAM TIP
Rt•••-tw,cber, stt:il.clctite I-las
ti-le letteY 'c' t:i""d LS forn.ed
o"" tne ceiti""fJ. stt:ilag"<ite
1-it:is ti-le lettey 'g' avcci is
foY1M.td o"' tt-ie gmu,,,.;_
Stalactites, stalagmites and pillars
• Wa ter seeping t hrough limestone is
very rich in dissolved calcium carbonate.
When the water evapora tes, for example
inside a large abandoned cavern, it
leaves behind a tiny deposit of calcite.
• If water is dripping down from the
ceiling, the calcite deposits slowly form
an icicle-like feature called a stalactite.
• Immediately below the stalactite, where
wa ter has dripped onto the floor of the
cavern, ca Icite may also be deposited to
form a stumpy stalagmite.
• Over thousands of years a stalactite
might become joined to the stalagmi te
below to form a pillar or column.
• Underground rivers may flow through
limestone to emerge as resurgences on
t he ground surface.
Figure 1.11.2 cavers explore a huge cavern
Limestone landforms in
the Caribbean
LEARNING OUTCOMES
• Understand the charactefistics
and format on of surface
karst landforms in the
Caribbean, nc uding <:ockpit
ka rst and tower karst.
• Understand the character sties
and formation of Harrison's
Cave in Barbados, an example
of an underground limestone
feature.
Limestone is widespread throughout the Caribbean, for example
in Cu ba, Jamaica, Barbados, the Bahamas and the Cayman Islands.
There are ma ny excellent examples of surface and underground
landforms.
Tropical karst landscapes
The term 'karst' is sometimes used to describe the barren dry
landscapes associated with limestone. The term itself comes from
sou thern Europe, from the Kras region in Slovenia.
Two distinctive types of tropical karst have been identified, both of
which exist in the Caribbean. They are cockpit karst and to,Ner karst.
Cockpit karst
• Cockpit karst 1s characterised by rounded conical hills rising up
lo about 150 m 1n height, separated by depressions called cockpits
(see f igure 1.12.1 ).
EXAM TIP
z:,?""'t ~o""f<A.Se cockpits
w•ti1 ct•""ts a""ol 0Yt1kes.
R.emembe,- ti1at ct,v,,t,s av,,ol
0t'):J"'es a,-e smaLL featuyes
ov,, _Limestov.e paveme""ts
wi1,te cockpits aye ci,-e,uLay
olep,-essio....s llon,ftYeol bu
'1iLLs.
u
Figure 1.12.1 Cockpit Coum,y in Jamaica
• The conical hills usually rise up to a uniform height.
• This landscape is thought to result from intens ve chemical
\'\leathering (carbonation) that is focused on widened joints and
solution holes, creating the cockpits.
• Cockpit karst may be part of a sequence of landscape development
(see f igure 1. 12.2) in tropical regions where limestone outcrops are
roughly horizontal and there is a regular pattern of joints.
• River erosion during times of higher water tables may have
contributed to the formation of the cockpits as \'\/ell as the collapse
of roofs of underground caverns.
Tower karst
• •
• Tower karst has a much more variable relief, with the hills rising
'Cockp t Country' was the name
given to the area by the British
in the 17th century because it
reminded them of the thenpopular cock-fighting arenas,
\>Vhich were hot, humid and
dangerous places where men
gathered to wa tch and bet on
the 'sport'.
to a range of different heigh ts (see Figure 1.12.3). The hills (to1Jvers)
are often steep-sided and may have caves and solution notches at
their base. Examples of tower karst can be seen m Chona, Malaysia
and Cuba.
• Tower karst may represent a landscape t hat has developed from
cockpit karst (see Figure 1.12.2). The tropical conditions lead to
active weathering and eros·on, eventually causing the towers to
break apart and collapse. The land between the towers becomes
flat as the cockpits are in-filled with sediment.
Harrison's Cave, Barbados
Harrison's Cave in Barbados exhibits many spectacular features,
including stalactites, stalagmites and pillars (see Figure 1.12.4). The
cave system was first identified 200 years ago but \>Vas only opened
to tourists from 1981. It is no,,,v Barbados' top
tourist attraction. There are several caves and
caverns open to the public and accessed by
Solution holes
tram. The largest cavern is the 'Great Hall',
Solution hole
which reaches a height of over 30 m.
Widened Joints
I
The surface is broken up by many small solullon holes but
lhe overall surface remains generally level.
Cockpil karsl
.
~
' '
' '
'
Cockpil ,
.
'
.'
I
'
IA
'
. .
~·
a
.I.
Water table
Cockptt karsl is usually a hilly area In which many deep
solution holes have developed to give it an 'eggbox·
appearance.
Tower karsl
Lt;,._
,
Towers
W1'er table
6.._
~
Sediments
'
"
.
'
, '
'
'
The widening and deepening of the cockpits has destroyed
much of the llmestone above the water table. Only a few
limestone towers remain. sticking up from a flat plain of
sediments that have filled In the cockpits at a level just above
the water table. Eventually the towers will be entirely eroded,
and disappear.
Figure 1. 12 .4 Harr son's Cave in Barbados
Flgu~ 1.12 .2 Features of tropical karst
'
Weather and climate in
the Caribbean
What is the difference between weather and
climate?
LEARNING OUTCOMES
• Understand the di fference
between weather and
cl ma te.
• Understand how weather is
recorded n 1he Caribbean.
• Understand the characteristics
of the Caribbean 's tropical
marine clima te
• Understand the effec1 of relief
on c imate.
• Weather - the short-term day-to-day cond ition of the atmosphere,
relating to rainfall, humidity, pressure, temperature, cloud cover
and winds.
• Climate - the long-term average weather, usually calculated over a
period of 30 yea rs.
While the weather may change from day to day the climate remains
the same. Any changes to t he cl imate take place over several decades.
Scientists have found evidence of a slig ht warming of the world's
clima te, which has led to the current issue of global warming .
The \'\leather varies from day to day and from place to place. A
coastal loca tion may be cloudy and a bit cooler than a place inla nd ,
and rain on the coast may fall as snow on the top of a mountain.
Some places have climatic conditions that are slig htly differen t from
neighbouring areas. Th is is known as a microclimate.
• Large towns and cities have slightly \¥armer climatic conditions
than nearby rural areas. This is because urban areas genera te heat
(bu ildings, t ransport and 'ndustries) and absorb and re-rad iate heat
from the Sun. This is called the heat island effect.
• Wood lands experience less varia tion in diurnal (daily) tempera tures
because the tree canopy provides shade during the day but
prevents heat escaping at night.
Weather in the Caribbean
Look at f igure 1.13. 1. It describes the weather forecast for Antigua
for five consecutive days. Notice that it includes details of the
tempera ture, rainfa ll, humidity, cloud cover and winds. The current
weather described at the top tells us that it is:
*
wind: from the north-east at 26 kph
relative humidity: 78%
barometer: 76.3 cm
temperature: 75 'F (23 •C)
air/sky: partly cloudy
C_0
5-0ay Forecast
weather station: Antigua
last updated: 5:14am CT
TUE
WED
THU
FRI
SAT
• partly cloudy with a temperatu re
of 75°F (23°C)
• the winds are blowing from the
north-east at 26kph
• it is humid (78 per cent) but not
ra1nmg
• the atmospheric pressure is 76.3cm.
The weather forecast for the next
few days is not so good.
rainy
rainy
rainy
rainy
rainy
82'F (27 °C) 82 'F (27 •C) 82•f (27 ' C) 80 •F(26 °CJ 82 'F (27 ' C)
to 73 •F(22 °C) to 71•F(21°C) to 71 'F (21 ' C) to 73 ' F (22 °C) to 73 °F(22'C)
Climate in the Caribbean
Figure 1, 13. 1 I \'\leather forecast for Antigua
The Caribbean experiences a tropical
maritime climate.
Average daily t emperature (•c)
J
Location
M
F
M
A
J
s
A
J
0
N
0
Kingston, Jamaica
30 (19) 30 (1 9) 30 (20) 31 (21) 31 (22) 32 (23) 32 (23) 32 (23) 32 (23) 31 (23) 31 (22) 31 (21 )
c.astr es, St Lu a
28 (21) 28 (21) 29(21) 31 (22) 31 (23) 31 (23) 31 (23) 31 (23) 31 (23) 2' (22) 29 (22) 28 (21)
Bridgetown, Barbados 28 (21) 28(21) 29 (21) 30 (22) 31 (23) 31 (23) 30 (23) 31 (23) 31 (23) 30 (23) 29 (23) 28 (22)
St Clair, Trinidad and
Tobago
31 (21) 31 (20) 32 (20) 32 (21) 32 (22) 31 (22) 31 (22) 31 (22) 32 (22) 32 (22) 32 (22) 3· (21)
Average daily maximJm (m n mum n brackets)
Average m onthly rainfall (mm)
Location
J
F
M
A
M
J
J
A
s
0
N
0
Annual average total
Kingston, Jamaica
23
15
23
31
'02
89
89
91
99
180
74
36
852
castries, St Lucia
135
91
97
86
150
218
236
269
252
236
231
'98
2,199
Bridgetown, Barbados
66
28
33
36
58
112
147
147
170
178
206
97
1,278
St Clair, Trn:dad and
Tobago
69
41
46
53
94
193
218
246
193
170
183
125
1,631
Figure 1.13 .21 Climate data for a selection of ocafons in the caribbean
• Tempera tures vary little throughou1 the year (21-27°C), althoug h
in the wet season (May-November) tempera tures tend to be a little
higher than in the dry season.
• Rainfall to1als are quite high (generally over 1,000mm a year) with
mos1 of i1 falling as tropical storms during the hurricane season
from June to November.
Look at Figure 1.13.2. It describes the climatic characteristics of a
selection of places in 1he Caribbean. No1ice that cl imatic condi tions
are broadly similar across 1he Caribbean .
Figure 1.13.3 is a cl imate graph that sho\<VS the climate for
Bridge1o\<Vn, Barbados. Notice 1hat temperatures are shown as line
graphs w hereas rainfall is shown using bars . This is a standard type of
diagram t hat you may be asked to in terpret in an examination.
30' ~ ~ irnurn
-
e_ 20·
1=
.3
!!!
.,
~
~
I
-
--
rn•nirnurn
-
C.
E
I
l
J
E
200 .§.
J
I
-
-
-
F M A M J J A
Months of year
~
s
0 N D
Figure 1.13 .31 Climaie graph for Bridgetown. Barbados
150 -~
a:
100
50
0
• • •
•
In 2009-2010 the Caribbean
countries of Guyana, Grenada,
St Lucia and Barbados
experienced a record drough t.
It began in October 2DD9 typically the region's wettest
mon th of the year.
Each of t hese coun tries recorded
their lowest ramfall totals
for October to March since
records began, according to
the Caribbean Institute for
Meteorology and Hydrology.
In Barbados as of 8 Aprl 2010,
there were more than 1,000
brush fires for the year to date,
compared with 361 during 1he
same period in 2009.
For more Information, go to
http://www.ncdc.noaa.gov/sotc/
hazards/2010/4#drought.
Factors affecting
weather and climate
LEARNING OUTCOME
Several factors affect the \'\leather and climate of a place. They include
latitude, altitude, relief, distance from the sea and winds.
• Understand the ma ·n factors
affecting weather and
cl mate.
Latitude
Latitude is the main factor affecting temperature. At t he Equator, the
Sun is directly overhead for much of the year. This results in a high
intensify (concentration) of insolation (see Figure 1.14.1 ), leading to
high temperatures. In contrast, at the Poles, the Su n is lower in the
sky. This causes the radiation from the Sun to be spread out over a
larger surface area and therefore the temperatures are lo\,ver.
Notice also on f igure 1.14. 1 that the radiation from the Sun has
to pass through a greater thickness of atmosphere at the Poles
compared \,vith the Equator. This accentua tes the temperature
differences.
The hig her temperatures a t the Equator resu lt in rising air, the
formation of clouds and periods o f heavy rain. This accoun ts for the
equatorial climate being warm and 'Net.
Near the Poles lnsolation has
more atmosphere to pass through
Solar radiation
(lnsolation)
•
~ Atmosphere
At the Equator lnsolatlon is concentrated, but
near the Poles It Is dispersed over a wider area
Figure 1.14.1 The effect oi lat 1ude
Altitude and relief
The al titude or relief of an area can affect both temperatures and
rainfall :
• Tempera ture - temperature decreases with al titude, roughly 10°C
every 1 km (1,000 metres) . Th,s is because as altitude increases,
air pressure is reduced and this causes a drop in temperatu re
(see Figure 1.14.2).
• Rain fall - if air is forced to rise up and over a mou ntain range it 1s
forced to cool. This will lead to condensation and rain formation.
This type of rainfall is called relief rainfall and it is common in the
Caribbean, as the St Lucia example on page 34 demonstrates.
Lower pressure s·c
High pressure
2s·c
Figure 1.14.2 The effect of altm,de or rel'ef
Distance from the sea (continentality)
Coastal areas tend to experience high levels of humidity and rainfall
and more moderate (less extreme) temperatures t han areas inland.
Such areas are said to experience a maritime climate. In contrast,
areas further inland, avvay from the influence of the sea, tend to
experience a more continental climate, with less rainfall and grea ter
extremes of temperature.
This factor is of little importa nce on most of the Caribbean islands
as they are too small to experience any degree of continentality.
However, elsewhere in the world (such as the USA and Europe), this
is an extremely important factor, accoun ting for very cold winters and
hot summers in the interiors.
Winds
Winds are important in transferring moisture and heat. The dominan t
wind direction is called the prevailing wind. The Ca ribbean is mostly
affected by prevailing winds from the north-east - the trade winds.
This explains why nort h· and east-facing coastlines may receive more
rainfall and experience more moderate tempera tures than further
west and south.
• • •
•
Wa ter has a higher spec ftc
heat capacity than land. It takes
five times as much hea t to
raise the temperature of wa ter
by 1•c than it does to raise
the temperature of land. This
explains \'Vhy land warms up and
cools down much more quickly
than water. Can you think why
\'Va ler has a higher specific heat
capacity?
al, drjfts out to sea,
day
ail' dtifts over land. cools,
night
cools, becomes dE!nser
becomes denser and sinks
and sinks
cooling may
provide a 'cloud
curtain'
descending air
low
sea br&ete
blows from
high to low
air in contact with land Is
heated, rises, and forms an
areaoflowerpressure ◄•i,...._ pressu,e
land heat~d more
rapidly than sea
nnsolation)
'
high
descending alt
cteates an a,ea
c,eates an area
of higher pressure
land breeze
blows ftom
-... ......-
of higher " - • - . . high to low
i
.
pressure
-..
pres.sute
-.....
~
-
high
h
sea ret21Ins, e.iu 1onger
than land: relatively
warm atrrises to givean
pressure
...p area of lower
high
land coo1smore
rap(dly thM sea
sea
sea
(radiation)
Figure 1,14.3 Land-sea breezes
Land an d sea b r eezes
Coastal areas can be aHected by local land and sea breezes, w hich
introduce cooler air, lowering tempera tures (see Figure 1.14 .3).
Factors affecting weather and climate in St Lucia
Look at Figure 1.14.4. No tice that the relief (variations in height) of
St Lucia has an impact on the pattern o f rainfall in the island . The
highest rai nfall totals are over the mountains tovva rds the sou th.
Rellel (metres)
Annual ralnlall {mm)
□ 0ver 600
0500- 599
0400- 499
0 200- 399
0 100-199
• under 100
Soufnere
O Underl,500
0 1,500-1,799
D 1,800-2,499
1:1 2,500--3.799
• ave,3,aoo
\
Mount Gi'11ie
•950m
• Petit Piton
Gros P1to1,if
,N
~ l"v
t
Vieux Fort~'
0 km 10
Figure 1,14.4 Rainfall and relief n St Lucia
Study Figure 1.14. 5 to see \,vhy the highest rainfall is over the
mountains.
South-west
Heavy rain over
mountains
Air sinks, warms
/
Air forced to rise, cools and
water vapour condenses
Mount
Gimie
"'---
North-east
Moist northeasterly trade
winds
------,_ _ _ _ _ _ jA/lanllc
Ocean
Figure 1.14 .5 Relief rainfa l over Mt Gimie, St Lucia
• The prevailing (most frequent) winds are the northeasterly trade winds . They bring warm, moist air to St
Lucia from the Atlantic Ocean.
• As this air reaches the mountains, it is forced to rise. It
cools and water vapour ·n the air condenses to form
thick clouds and heavy rain.
• High amounts of rain falls over the mountains.
• When the air descends, it \'\/arms and becomes drier.
This drier, sheltered down-slope region is sometimes
called a rainshadow.
Mountains tend to experience lower temperatures than
lowla nd areas, decreasing by 1°C for ever; 100 m of
ascent. This is caused by a reduction in air pressu re wi th
increasing altitude.
SUMMARY QUESTIONS
1 Use a labelled diag ram to explain why equatorial
regions experience higher temperatures than polar
regions.
2 How and why might the east coast of a Caribbean
island experience weather that is different from
that fn the 'Nest?
3 Explain the formation of a sea breeze.
Figure 1~14.6 Mount Gim,e, St Lucia
Equatorial and tropical
maritime climates
Equatorial climate
LEARNING OUTCOME
Figu re l .15.1 shows the global distributio n of the equatorial climate.
It broadly corresponds wi th the distribution of the tropical rainforest
biome. The main characteristics of the equatorial climate are:
• Understand the ma ·n
characteristics o f equator al
and trop ca maritime
cl mates.
• ho t conditio ns- generally 26°C or higher throughout the year
• hig h rainfall totals, in excess of 2,000 mm per year
• lack of d istinctive seasons (summer/winter) but there is a wet/
dry season - for example, in M anaus, the wet season lasts from
November to May whereas in June-October it is rela tively d ry
• greater diurnal (daily) range in temperature than seasonal
differences (see the climate data for Ma naus, Brazil in
Figure 1.1 5 2).
Rainfall usually takes the form of torrential downpours in the
afternoon as clouds build due to the high humidity and rismg
tempera ture. Cloud cover restricts tempera tures d uring the day so
tha t it never becomes excessively hot.
Figure 1.15, 1
The eqcator'al d :mate
J
F
M
A
M
J
J
A
s
0
N
D
Average monthly
temperature (°C)
28
28
28
27
28
28
28
29
29
29
29
28
Vlonthiy total
rainfall (mm)
278
278
300
287
193
99
61
41
62
112
165
220
Flgure 1, 15.21 Cl mate dasa <or Manacs, Braz I
Tropical marine climate
Figure 1.15.3 shows the distri bution of the
tropical marine climate. It is focused on
eastern coasts of tropical lands, exposed to
the trade winds throughout the year. It is
the clima te experienced across most of the
Caribbean . The main characteristics o f the
climate are:
·--·····- -----·
Cmt~~f
• high temperatures, usually in excess of
26° C
• hig h rainfall, betvveen 1,200 mm and
2,000 mm per year
figure 1 .1 5.3 The tropical marine cl 'mate
• d istinctive wet and d ry season, w ith the
hig hest rainfall to tals being in the late
su mmer and autum n (see the cl imate data
fo r Montego Bay in Figure 1.15.4).
• • •
In the Caribbean, the north -east trade w inds blow all year round,
bringi ng moisture from the Atlan tic Ocean. Rain ca n take t he form
of relief rainfall, w here the air is forced to rise over moun tains, o r
convectiona l rainfall triggered by high tempera1u res du ring the
afternoon.
Some tropical waves develop
into tropical depressions or even
hurr canes.
Places w ith tropical marine chmates may also experience tropical
waves (see page 41 ). These are belts o f low pressure w hich generate
a heavier burst of rainfall.
J
F
M
A
M
J
J
A
s
0
N
D
Average mo nthly
temperature (' C)
25
25
26
26
27
28
29
29
28
27
26
26
Month y total
rainfall (mm)
70
30
30
60
80
80
60
80
110
130
120
100
Figure 1.1 s.41 Oimate data for Montego Bay, Jamaica
SUMMARY QUESTIONS
1 Study Fig ure 1.15.2. Draw a climate g raph for
M anaus and add labe's to d escribe the main
characteristics of the eq uatorial climate.
2 How does the tropical marine climate differ
from 1he equato rial climate?
Caribbean weather
systems
LEARNING OUTCOMES
• Understand the global
atmospheric o rculafon.
• Understand the forma tion of
the ITCZ.
• Understand the formation of
common \-veather systems in
the Car"bbean (anticyclones,
cold fronts and tro pical
waves}.
The global atmospheric circulation
The \,veather systems affecting the Carib bean are part of the global
atmospheric circulation. Look at Figure 1.16.1. Notice that there
are three la rge circu lation cells in each hemisphere. These cells are a
major influence o n the ~veather experienced on the g round.
Notice that the Caribbean lies beneath the Hadley Cell in the northern
hemisphere. It is this part of the global atmospheric circulation that is
responsible for much of t he \-veather experienced in the Caribbean.
• A t the boundary of the two Hadley Cells, close to the Equator, air
converging at the ground is forced to rise. This creates an unstable
zone of cloud and rain called the Inter Tropical Convergence
Zone (ITCZ). The posi tion of the ITCZ is largely determined by the
position of the overhead Sun .
• At about 30° Nair is sinking towards the surface. This forms a large
area of high pressu re called an anticyclone. This is responsible
for crea ting t he prevailing north-easterly w inds - the trade w inds that blo,N towards the Caribbean for much of t he year.
• As the overhead Sun moves between the Tropic of Cancer and
the Tro pic of Capricorn, so the circulation cells shift slig htly north
and south of the Equator. This explains the changes in \'Veather
experienced in the Caribbean during the course of a year.
Troposphere
,
30't\
30' N
North-east \ Hadley
trades
\ \ Cell
Equator
ITCZ
'\
Stratosphere •
Antitrades
Earth
30' S
South-easy
trades
H di
a ey
Cell
Antitrades
30'~J
Clear conditions
,'
,I
'
F1gure 1, 16 .1 Genera c.rcu!ation mode1 and the caribbean
Th e Inter Tropical Convergence Zone (ITCZ)
The ITCZ is a broad zone o f very unstable weather t hat forms at t he
boundary of the two Hadley Cells (see Figure 1.16.1).
• At the ground surface, warm moist air converges and is forced to rise.
• This resu lts in rap id cooling and the forma tio n o f tov;ering
thunderstorm clouds (see Figure 1.16.2).
In winter (in the northern hemisphere) the ITCZ moves south to
lie close to the Equator. The \'\leather in much of the Caribbean is
affected by the large anticyclone to the north and is general y settled
with more sunshine and less rai nfall.
In summer (in the northern hem isphere), as the overhead Sun moves
nort h of the Equator, the ITCZ shi f ts northwards to affect much of
the southern Caribbean. This accounts for the heavy rain fall and more
unsettled conditions experienced in the regio n.
The ITCZ brings periods of very heavy rainfall to countries in the
southern Caribbean, such as Trinidad, St Lucia, Guyana and Barbados.
It is responsible for the marked ~vet season that occurs in these
regions beh,veen June and November (see Figure 1.13.2, page 31).
The ITCZ is also an important factor in the forma tion o f hurricanes
(see pages 42- 5), w hich explains w hy the Caribbean is most affected
by hurricanes in the period between August and November.
Air diverges and moves poleward
.-.◄---.....:::, l
r-----~.,
Air cools, condenses
and forms towering
storm clouds
HADLEY
CELL
HADLEY
CELL
• • •
Air converges and rises
--
.,
He.avy rain
0'
Equator
Figure 1. 16.2 Formation of the ITCZ
-
•
The Hadley Cell \,vas identified
by the Englishman George
Hadley in 1735. He developed
the sim p e rr,ode of a c,rcular
trop,cal ce heated by the
Sun's energy to explain the
existence o f the trade winds. He
recognised the importance of
the Earth's rota tion in affecting
the winds and weather systems
in the tropics.
Anti cyclones
24
<1\
An anticyclone is an area of relatively high
atmospheric pressure that causes settled
'Nea ther conditions. The \'\leather associa ted
wi th an anticyclone is often sunny and there
'Nill be little rainfall.
Look at f igure 1. 16.1. Notice 1hat a large
anticyclone, which is known as the Azores
High Pressu re Cell, has formed at a latitude
of abou1 30° N, to the north of the Hadley
Cell. This ,s because air is sinking in 1his region
leading to the high pressure on the ground.
This an1icyclone is responsible for t he dry
season months experienced throug hout much
of the Caribbean.
•
Cross-seclion lhrough a cold Iron!
SE
NW
Towering
cumulonimbus
clouds
Warm air
rises along
the front
Cold
air ,...,,~-►►
Figure 1.16.3
Cold front
Warm air
As \'Vinds circulate around this area of high
pressure they blow towards 1he Ca ribbean
from the north-east. These are 1he north-east
tra de winds and they form 1he preva iling
winds in the region.
The sinking air reduces the likelihood of
surface air rising, cooling and condensing
to form cloud and rain . With an absence
of clouds, long hours of sunshine will be
experienced. At night, temperatures can fall
sharply as surface heat escapes to space.
Cold f ronts
Occasionally in the winter, cold air sweeps
across parts of the nor1hern Caribbean from
North America. The boundary of this colder air
on 1he ground is called a cold front .
Figure 1.16.3 shows a cold front on a weather
Synopt,c map showing northers (a cold from)
map. Notice that the V'tarmer air ahead of the
cold front is forced to rise. This forms cloud
and heavy ra in, which can be damaging to
crops on north- facing slopes. The northerly wmds behind the cold
front are locally known as northers.
Some Northers have reached as far south as Trinidad , bringing
periods of heavy rain and a drop in temperature. The cold air from
the USA is warmed as it moves south and travels over the Caribbean
Sea. This means that the tempera1ure drop is less significant in the far
south of the region.
.'
Tropical waves
Tropical waves are belts of relatively low pressure t hat travel across
the Atlantic Ocean along the edge of the ITCZ. They bring periods
of unsettled weather with heavy rain, most commonly between May
and November.
As Figure 1. 16.4 shows, the trade winds have a relatively moist lower
layer and a drier upper layer. If a wave develops (rather like a wave
at sea), the moist surface layer rises to a height of 7,000 m or more.
A1 this altitude. air becomes sufficiently cool to condense and form
cloud and ra in.
Tropical 'Naves are generated by heat, \'Vhich forces the air to rise,
creating an area of relatively low pressure. They are large features,
often extend ing over 1,000 km. This mea ns that unsettled \'\leather
could last for several days in any one place. Once a tropical wave has
passed, 1he wea ther will tend to be cloudy for a few days.
._
Metres
7,000
<l
>
.5l
Drier upper
tradewinds
6,000
"'.,
"'
~
5,000
Boundary of
4,000
moist air
3,000
J:
2,000
-"'..
0
·.;
""
:,::
1,000
0-
----
Trade wind stream
... zone r
::...
::;,:;........::,,.
.............
..... .,, .... ..
,'.'.',',';
1/
-------/
'
,
'
MolitsUfla<;e
. ' layer
....
·'.
"
'
....___
500-1,000 km
Figure 1. 16 .4 Cross-section oi a tropical wave
,,.
. .
41
.
----;;_
'
Hurricanes
LEARNING OUTCOMES
What is a hurricane?
• Understand the defin tion of
a hurricane.
Look at f igure 1 .17. 1. It is a satellite pho to of a hurricane in the
Carib bean. Can you see the 'eye' of the hu rricane, right in the cen tre
of the swirling mass of cloud?
• Understand how hurr"canes
form and develop.
A hurricane is a massive and very PO'Nerful tro pical storm that can
cause widespread destructio n and loss of life. The Caribbean is of1en
affected by hurricanes that form over the Atlantic Ocean off the
coast o f West A frica and then move westwards. They usually occur
between July and November. The official hu rricane season is from
June to November.
What forms a hurricane?
While scientists are not certain w hat triggers a hurricane, they tend to
form in the following cond "tions:
• over warm \'\later (over 26.5°C), w hich explains \,vhy they occur in
the tropics
• \'\/hen sea temperatures are at their highest
• at a latitude g reater than 5 degrees North or South. Closer to the
Equator the air is calm in the 'doldrums' and there is no t enough
'spin' resulting from the rota tion of the Earth
• in tropical regions o f severe air instability (ITCZ) where air is
converging o n the surface and rising rapidly.
When these conditio ns occur a hurricane can form . f igure 1.17.2
shows the main hurricane-forming regio ns of the world and the
common tracks taken by hurrica nes.
How do hurricanes develop?
Look at f igure 1 .17.3, which shows a cross-sectio n through a
hurricane. This is how a hurricane forms and develops.
• Air n ses rapidly over a warm ocean \'\/here huge quantities of water
are evaporated very quickly. As the air rises it cools and the vapour
condenses to form cloud .
• The rotation of the Earth sets up a spinning motion and the storm
assumes its cha racteristic Catherine-wheel shape, spinning in an anticlockwise direction (in the northern hemisphere) (see Figure 1. 17 .1).
• The area of disturbed weather that forms is first described as a
tropical depression and is given a number. If the winds intensify then
a lropical storm forms and the wea ther system is given a name.
• \Nhen su rface \'\finds reach an average of 120 kph the storm
officially becomes a named hurricane.
• Once formed, the hurncane is carried across the ocean by the
prevailing \'\finds from east to west .
• On reaching land, the supply of warm water (the hurricane's fuel) is
cut off and the storm begins to weaken.
Notice on Fig ure 1. 17.3 the narrow tube of cold dense air sinking
towards the surface in the centre of the storm. This 1s the eye of the
hu rricane that you can see clearly in f igure 1 .17. 1. The edge of t he
eye is a towering ba nk of cloud called the eye wall. It is here that the
strongest vvinds will be experienced .
Hurricanes
Auir-Oc1
Tropic of
Equator
1
June-0ct
\
Tropic of Capricorn
9
/
2,900km ;
'
r
17% Percentage of global
Areas of fofl11ation
total of tropical
~ Main hurricane paths
cyclones in each zone
Local names given and
for the period 1958-77
season of occurrences
ncer
n \
Northem hemisphere --,....It!
....to,!al: 69%
% \
Typhoon
May,aDec-Eastern Asia
c. , adagascar
/
33%
_~.
0
13%
Jan-Mar
11%
Dec-Mar
\i.
Fi ure 1. 17.2 The location and tracksof hurr·canes
4 Co air in , entre sinks
14
+--.__ /""\
I
-"'
. Ql
<.>
:c
i
0
r
Approach of hurricane
70-100 km
:Temperatures and pressure
,begin to fall. Winds are gentle
:and from the north-west.
!Clouds begin to form and
:showers develop. Wind
! begins to gust.
1
14
I"'-. ,,...+3
j
ll
J
I
~
l,
bus clouds and heavy rain
I
upwards
1 warm, moist air is forced to rise
:
30-50 km
30-50 km
l 5-2Ebekm
, Pressure falls
; Period of ;Onslaught begins
: rapidly. Wind
,calm.
;again, with
! speeds increase - : Pressure :hurricane-force
: up to 100 kph.
!very low. !winds and
: Cumulonimbus
; Tempera- ;torrential rain.
: clouds with thunder : tures rise :Winds now in
! and torrential rain j as the Sun j south-east.
, (250 mm In aday). ; makes a :Temperatures drop
!
j brief
jagain, but pressure
;
; appearance.; begins to nse.
Direction of hurricane movement
Agure 1.17 .3 The structure of a harricane (in the northern hem,sphere)
j
End of hurricane
70-100 km
; Pressure and temperatures
; rise. Rain decreases to
:showers and some sunny
j.Intervals. Winds decrease.
...
...
..
.
.
.
0
LEARNING OUTCOMES
• Understand the effects of
a hurricane on sands and
coastal regions
• Understand the irrpacts of
hurrcanes on the Car'bbean.
• Understand how the mpacts
can be reduced.
W hat are the effects of hurricanes?
Hurricanes can have a number of effects on islands and coastal
regions.
• Strong winds. With wind speeds in excess of 120 kph and gusts
of over 200kph, hurrica nes can cause a g reat deal of damage.
Roofs will be blown off houses, power lines torn down and crops
fla ttened .
• Heavy rainfall. The torrential rai nfall (often over 200 mm) associated
v;ith hurricanes can bring v;idespread flooding and landslides,
damaging roads, bridges, crops and buildings.
• Storm svrge. Driven onshore by the strong winds, h;gh seas (often
3-Sm in heigh t) surge inland over low-lying areas and up river
valleys. Storm surges caused by hurrica nes a re the biggest killers.
A storm surge will flatten everything in its path rather like a tidal
vvave. It will destroy crops and inundate vast areas wit h salty water.
/ CASE STUDIES
I
1 Hurricane Omar 2008
2 Hurricane Ivan 2004
Hurricane Omar developed in t he eas1ern
Caribbean Sea in October 2008. It took a n
unusual 1rack south-west\,vards and t hen turned
to the north-east, intensifying to become a
category 4 hurricane wi th a wind speed up to
215kph.
In September 2004, Grenada was devasta ted
by a powerful category 4 hurrica ne that caused
immense damage to the isla nd a nd killed 39
persons. The to tal damage was estimated at
over USS 1 billion.
Hurricane Omar struck the Caribbean islands
of Antigua a nd Barbuda causing over
US$50 million damage, destroying several
homes a nd devastating farmland . Large areas
were inundated by floodwa ter and services such
as electricity were cut off. Puerto Rico was also
badly affected.
Despite the widespread and costly damage
nobody was killed by the hurricane. This was
thanks to careful forecasting a nd pred iction by
scientists who were able to use satellites a nd
radar to track the storm. VVarnings \<Vere given
and many locals were moved to higher ground
and to the safety of hurricane shelters. On
Anguilla tou ris ts \'Vere told to leave t he isla nd
ahead of the s torm.
• Over 14 ,000 homes were destroyed as the
island was lashed by 200 kph winds and
18,000 persons were le ft homeless.
• Almost every building in the capital,
51 George's, \'Vas damaged o r destroyed by the
hurricane.
• 75 ou t o f 1he 77 schools on the isla nd were
damaged or destroyed .
• Services such as \'Valer and electncity were cut
off.
• There was widespread damage to cro ps,
resulting in losses o f up to 90 per cent.
How can the
hurricane hazard
be reduced?
Satelli1e and radar enable
scien1ists to view and
to track hurricanes, and
computers can be used to
predict their likely course.
Warnings are then issued
to areas at risk.
Hurricane Watch - Be
prepared! Hurricane
conditions are likely in t he
next 36 hours. Batten the
windows, collect ~vater
and emergency supplies.
Hurricane Warning -
n me to act! Hurricane
conditions are expected
in 12- 24 hours. Evacuate
lo\,v-lying areas or seek
shelter.
Atlantic Ocean
NORTH AMERICA
I
'/
(
Gull of
/ 4ck of Hurricane
Omar2008
../'
Puerto Anguila
Mexico
RIC:
/
l,;~---Barbuda
r
Jamaica
Caribbean
Sea
//
::.------ Grenada
~
SOUTH AMERICA
--
-- --
Track of Hurricane Ivan 2004
Figure t .17.4 Tracks of Hurricane Omar (2008) and Hurricane Ivan (2004)
Those living in the Caribbean are a\,vare of the dangers of hurricanes
and kno\,v how to respond when warnings are issued. Many areas
have hurricane shelters, which are strong and secure build ings
constructed to withstand the full fury of the storms. Despite these
preparations, hurricanes continue to be a major threat to the
residents and economies of the Caribbean.
• • •
Ca ribbean hurricanes
Figure 1.17 .5 A demo•1shed bollding front a'ter Hurricane Ivan
The Abaco Is ands have been
struck by 1B severe hurricanes
since 1851 . They are the
hurricane 'capital' of the
Caribbean. Smee 1944, Cuba,
Key West and Nevis have
been struck by 7 major storms
(roughly one every 8-9 years).
Bonaire and Cura~ao have been
struck the least.
Global warming evidence and causes
LEARNING OUTCOMES
• Understand the meaning of
global \<Varming.
• Understand the sc1ent fie
evidence for global warr'ling .
• Understand the causes of
global warming and 1he
concept of the greenhouse
effect.
What is global warming?
Global warming is the term used to describe the increase in average
g lobal temperatures that has taken place in the last few decades.
Scientists believe that global temperatures have risen by 0 .74°C since
1900 and by 0 .5°C since 1980. This may no t sound very much bu t it
is a global average - in some places tem peratures have increased by
much more.
This t re nd is expected to continue. By 2100, the average global
tempera ture could increase by 1.8°C to 4.0°C. This would lead to
considera ble changes to the world's na tural ecosystems a nd the
world's climates. The poss•ble impacts of global warming will be
d iscussed in Unit 1.19.
08- - - - - - - - - - - - - - - - - - - -
g
"'
5J
-;g'
0
I»
Ii i;
Jl1 E
0.6 -----------------•
04 - - - - - - - - - - - - - - - -'
0.2
0
'6 ~
I!? 6, -02 -
!~
What is the evidence for
global warming?
Evidence comes from direct
temperatu re readings, together with
the study of histonc records.
Instrument readings
-
-0.4
' -06---------------------
p
-OB--------------------1880
1900
1920
1940
1900
1980
2000
2020
Ve.a.-
Figure 1. 18. 1 Global temperature change since 1850
Direct measurements of
temperature using thermometers
have been ta ken since about 1850.
Ho\-vever, it 1s only in the last few
decades tha t thermometers have
provided accu ra te in forma tio n
across the world. Since 1980, direct
measurements have recorded a clear
upward t rend, providing very strong
evidence fo r global warming.
Ice cores
When snow falls and turns to ice, water molecules and air bubbles
become tra pped a nd provide a frozen record o f the Earth's climate at
the time when the sno,N fell. Scient ists have taken deep ice cores in
Antarctica a nd Greenla nd and have a nalysed the \<Valer and t ra pped
a ir. Their results suggest a stead y rise in tempera ture over the last few
decades.
Arctic ice cover
Figure 1. 18. 2 An ice core being
examined in the Antarct c
' ;
Over the last 30 years, the Arctic ice has 1hinned to a lmost half its
earlier thickness. In the fu ture, scientists believe th at pa rts of 1he
Arctic may become completely ice-free du ring the summer. By the
e nd o f !he cen1ury, !here may no longer be any Arctic ice.
Gla cier retreat
• •
The World Glacier Monitoring Service estimates that up to 25 per cent
of global mountain glaciers could have disappeared by 2050. There is
considerable photog ra phic evidence of rapid gla cier retreat across the
world, supporting the belief t hat the \,vorld is becoming warmer.
Global.y; the \,varmest year o n
record was 2015 - bu t it was
probably 2016 . Re<ords show
that 1 5 of the 16 warmest years
have occurred s·nce 2000.
What are the natural causes of global warming?
To unders tand the causes o f glo bal warming, you first need to
u nderstand an important natural fea ture of the atmosphere called the
greenhouse effect.
Look at Figure 1.18 .3 and
notice how it works:
• Incoming short-wave
radiation (visible light)
from t he Sun passes largely
uninterrupted through the
atmosphere to reach the
Earth.
Greenhouse gaaea (able to absorb heat}
• Car'oon d OX•C~
• Methane
• Nit,ous oxid$$ \
Atmosphere
{
lor.g•wave rao..ation Reflec11on aid
hem Eanh abscted
s:an8, .ng
. .. .
In ttie atmosptie1e
.•
· .
• ·
.
..·
. • •
• Partic~s (e g. dus1)
•
• • • . f'> . . .
. ·,
,
• Gases \e.g n,trogen) . , . , , • • I , . • '
•
•
• Liquids (e 9. wa:er)
.
Earr, warms up ar.Q ~Ives ofl
.
lnooming sh:r:-wave
so:ar rad.al on
•. • Some long-wave
· . · radia: on eseao~
~ - - - - - -10_"..:0_•w_·av_e_,a_d_~t_,on_ _ _ _ _.....c:,,,. to si;:ace
• The incoming solar radia tion
• Si-tort-wave aol~ radla:ion Long•·Na•1e Ea'1h , actia~on
that heats the Ea rth is called
insolation.
Figure 1, 18.3 Greenhocse effect
• This energy heats up the
Earth's suriace, which ·n
turn gives oH heat in the form of long-wave radiation .
• Some of this heat from the Earth escapes to space but some is
tra pped a nd absorbed by greenhouse gases in the atmosphere.
• This warms the atmosphere, creating a kind o f insulating bla nket
around the Earth . This is the greenhouse effect Without it, the
temperature would be too cold and li fe \,vould no t exist on Earth .
How have human
activities affected global
warming?
Scientists believe that, in recent
decades, there has been an
increase in the emissions of
g reenhouse gases, fo r example
carbon dioxide released by burning
fossil fuels in power sta tions
(see Figure 1.18.4). The increased
concentration o f greenhouse gases
in the atmosphere has resulted in
more heat from the Earth being
absorbed, thereby increasing the
greenhouse effect.
Ma ny scientists believe that this
enhanced greenhou se effect
resulting from human activities
accounts for the recent rise in
global temperatures.
Greenhouse gas
Human contrib utions
Carbon d ioxide: accounts for
an estimated 60 per cen t of the
'enhanced' greenhouse effect.
Global concentra tio n of carbon
d ioxide has increased by 30 per
cent since 1850
Burning fossil fuels (e.g. oil,
gas, coal) in industry and power
statio ns to produce electricity,
car exhausts, deforestation a nd
burning wood
Methane: very effective in
Decaying organic matter in
land fill si tes and compost tips,
rice farming, farm livestock,
burning biomass for energy
absorbing heat . Accounts for
20 per cent of the 'enhanced'
greenhouse eHect
Nitrous oxides: very small
concentrates in the atmosphere
are up to 3 00 times more
effective at capturing heat than
carbon dioxide
Figure 1.18.41 Greenhouse gases
Car exhausts, power sta tions
producing electricity,
agricultural fertilisers, se\,vage
treatment
The effects of global
•
warming
The effects of global warming worldwide
LEARNING OUTCOMES
Most scientists agree that global warming is happening and that it is
likely to have an impact on the vvorld's natu ral systems. It is, however,
uncertain what those effects will be and vvhich parts of the world wil l
be affected most.
• Describe and expla n the
possi ble impacts of g obal
warming.
• Understa nd that global
warming may bring
both advantages and
disadvantages.
• Understand the possible
impacts on the Caribbean
Any effects of global warming will take place over a long time period,
probably decades. Only through looking at long-term trends will
scientists be able to conclude wi th any certainty that global \'\/arming
1s having an impact. Any single event, for example a powerfu l
hurricane, cannot be blamed on global warming.
Predictions about the likely impacts of global \'\/arming are made
using computer models. Some of the possible impacts, both
advantages and disadvantages, are described belo\'\I and shown in
Figu re 1. 19 .1 .
Advantages
• Current cold environments will become warmer and \'Viii be able to
gro\'\I food crops.
• Areas where cereal crops, such as wheat, are grown may become
more extensive O\'Ving to a longer gro\,ving season, increasing the
production of food .
• Canada 's Northwest Passage may become ice-free, allowing it to be
used for shipping.
rler condlbons
reduce grain haivest
More temoerate
ellirale leads 10 Increased
wheat produc1101
-
Likely to be flooded
by rise In sea level
Wellerthan now
Drier than now
Flgure 1, 19.1 Possible impacts of g!obal warm'ng
•
• As temperatures increase in densely populated areas, demand for
energy for hea ting may fall.
• •
• There may be fewer deaths or injuries caused by cold weather.
In Siber a, warmer temperatures
have led to melting of the
permafrost (permanen tly frozen
ground), releasing methane,
a greenhouse gas, into the
atmosphere.
Disadvantages
• Global sea levels are expected to rise by 18-59cm by 2100, putting
low-lying islands and deltas at risk from flooding. Such areas
include the Netherlands, Bangladesh, the Maldives, the Cayman
Islands, t he Baha mas, and Turks and Caicos in the Caribbean.
• Parts of Africa may become d rier,
leading to droughts, migration and
possibly increased famines.
• Cereal yields may fall in parts o f India,
Africa and the Middle East.
• Melting glaciers in the Himalayas may
increase flooding in Nepa I, India and
China.
• Hu rricanes may become more violent
in the North Atlan tic.
• An addi tio nal 220-400 million people
may be at risk from malaria in China
and central As;a_
• Climate change w ill affect ecosystems
and some species; for example polar
bears in the Arctic may be threatened
by the melting of the floating ice that
they need for hunting and survival
(see Figure 1.19 .2)
' CASE STUDY
Figure 1.19.2 Are polar bears i1ke!y to become ext net in the future?
Irr.pacts of climate cha nge in the Canbb ean and L;SA
Caribbean
USA
• Rising sea levels could flood low-level islands
such as the Bahamas and the Cayman Islands.
• Weather patterns could cha nge significan tly,
bring ·ng floods to some areas and drought to
o1hers.
• Increased ra tes o f coastal erosion could threaten
beaches and coastal ecosystems. This in turn
could have a negative impact on tourism.
• Modera te wa rming may lead to Increased cro p
production .
• The warming of tropical seas can cause harmful
bleaching of corals. Between 2005 and 2015,
an estimated 300 km of Belize's barrier reef
v;as bleached and it could die. With global
\'\'arming, this could become more extens;ve,
t hreatening the fishing industry and tourism.
• Fragile moun1ain and arctic ecosystems may
suffer habi1at loss and some species may
become exti nct.
• Warmer ocean temperatures could result in
more intense hu rricane activity, which could
prove very costly to t he Ca ribbean.
• Tropical diseases could spread more \,vide!y,
t hreatening human health.
• Erra tic rainfall could affect crop yields, water
su pply and irriga tion, leading to poverty and
migration .
• Sea-level rise could flood low-lying coastal
areas, e.g. the Gu lf of Mexico and parts of
Florda's coastal wetlands.
• Warm ng will increase electricity demand, e.g .
for air conditioning.
Reducing the impact of
global warming
LEARNING OUTCOMES
• Exp ain how Ind vid uals,
national governments and
international ag reements can
address the issues of global
warming.
• Descn be rene\lVab!e energy
projects in the Car bbean.
How can greenhouse gas e missions be reduced?
Individual actions
Individuals and local communities have a very important part to play
in reducing greenhouse gas emissions. Ways to achieve this ·nclude
the following :
• Conserving energy at home by using low-energy lig ht bulbs,
swi tching off electrical appliances when not in use and wearing an
extra swea ter rather tha n turning on the heating (i n colder regions).
• Walking, cycling or using public transport rather than private cars
to reduce vehicle emissions.
• Reducing waste by recycling materials.
• Becoming involved in campaigns to put pressu re on governments
to reduce emissions.
National actions
Governments ca n adopt policies to red uce emissions. These might
include the follov,ing:
• Setting ta rgets for reduction in emissions.
• Encouraging renewable energy production, such as wind, solar and
hydroelectricity, by providing g rants and tax incentives.
• Using technology and intro ducing strict regu lations to reduce
emissions from power stations and car exhausts.
• Encouraging the development of public transport systems,
pa rticularly in towns and cities .
• Encouraging people to recycle and to red uce waste.
• Providing g rants for people to insula te their homes to reduce
energy consump tio n.
International actions
Global warm ing is an international problem that spreads beyond
national borders. In the long term, the solu tio n to the problem has to
be through ·nternational action.
ar-
-
In 2005, the Kyoto Protocol became in ternatio nal law. It states that:
Over 170 countries agreed to reduce carbon emissions by an average
of 5.2 per cent below their 1990 levels by 2012 . Of the maj or
g reenhouse gas emitters, only Australia and the USA refused to sig n
the treaty.
In 2015, 195 countries adopted the Paris Agreement, the fi rst ever
u niversal and legally binding global climate deal. The major target
1s to keep the global temperature increase below 2•c and li mit it
to 1.5°C above pre-industrial levels. Prog ress w ill be reviewed every
five yea rs.
Carbon trading and climate protection payments
Carbon trading
If a coun1ry or organisation within a country has cu t its ca rbon
emissio ns to a level that is below its ta rget, it has 'spare' carbon
credi ts. These carbon credits can then be traded (carbon trading)
with a country or organisa1ion that has not been able to cut its
emissions. Overall, a balance is maintained through internatio nal
cooperation and trade.
Tree-planting prog rammes ca n also
be used lo 'buy' carbon credits. Trees
absorb carbon dioxide and 1herefore
remove it from the atmosphere.
Climate protection payments
In many tropical regions, burning is
used as a method to clear rainforest
land for agriculture. This releases
huge quantities of carbon d ioxide
m1o 1he atmosphere. A recent
approach lo reducing emissions has
involved the mterna1ional community
throug h climate protection
payments, which es1ablishes a
value for an area o f forest and
pays governmen15 not 1o carry out
defores1a tion. In this way emissions
can be reduced and importan t
natural ha bitats protected .
Renewable energy in the Caribbean
In an attempt to reduce ca rbon emissions, several countnes in the
Caribbean have introduced renewable energy projects:
• Jamaica - supported by the Netherlands, 1/\figton wind farm has
23 wind turbines and already meets Jamaica's
renewable energy targ ets.
• Barbados- there are over 32, 000 solar water
hea ters o n 1he roofs o f h ouses, businesses and
hotels. They save around USS6.5 million in fuel
that vvould o therwise have been imported .
• Barbados is considering the use of offshore \<Vind
turbines lo genera1e electricity.
• St Lucia, Dominica and Grenada - these countries
are seeking to become the world's first noncarbon-fueiled economies by developing wind,
wave and solar power to meet all their energy
needs.
• Nevis, St Lucia and Dominica - here there are
opportunities for exploiting geothermal energy.
•
LEARNING OUTCOME
• Understand the ind ividual
and government responses
to global warlT'ing n a
developed country, the UK.
Responses to global warming in the UK
The growth of the 'green' movement
In common wi th many countries, the UK has seen a g rowing public
av,areness and concern abou t environmen tal, or 'green', issues. All
the political parties in the UK have policies aimed at conserving the
environment and reducing the impact of global warming. Actions are
ta ken by individuals, focal authorities and the government to try to
reduce the emissions of greenhouse gases.
Individual responses
in some parts o f the UK,
parents and their children are
encouraged to join together
with o ther parents and children
to form a 'walking bus' to travel
bet\,veen home and school. This
cuts down o n the use of vehic es
and provides children (and
parents!) wi th useful exerc•se.
Energy conservation
lndiv1d ual households conserve energy by usmg lovv-energy
appliances and double glazing to retain heat during the winter.
Governmen t grants are ava ilable to encourage people to use solar
panels to generate electricity that ca n be fed into the national grid . In
some areas, grants are also available for home insulation.
Recycling
Waste recycling is \,videspread, \'Vith products such as paper,
cardboard, glass and plastics being sorted in homes before being
collected to be recycled . Households are encouraged to compost
kitchen waste.
Carbon offset payments
Some people choose to pay a ca rbon offset fee when making
bookings for airline flights. Air travel is a hig hly polluting form o f
tra nsport and is responsible for emitting g reenhouse gases into the
atmosphere. These paymen ts can be used to plan t trees.
Figure 1,20.4 Solar panels on the roof of a house in the UK
Government responses
Developing renewable energy
The UK government is committed to red ucing carbon emissions
by 80 per cent by 2050. 1\/luch of this saving \'Viti come from the
development o f renewable energy. By 2020, the UK aims to meet
15 per cent of its energy req uirements from renewa ble sources.
The UK is fo rtu nate in having a vanety of op tions for renewable
energy, including w ind, wave, hydroelectric and geothermal. Much
of the focus in recent years has been on the construction of wind
fa rms. Wind power contributed 11 per cent of the UK's electricity
generation in 2015. The UK is the sixth largest producer of wind
energy in t he world, w,th around 7,000 w ind turbines in operatio n.
•
.. . . ~
. -~.
..
1·a.
.. .. -
•
Figure 1.20.5 An oikhorewir.d farm
Reducing vehicle emissions
The UK has in traduced stricter M OT (Ministry of Transport) tests o n
vehicle exhausts and it has set higher taxes for vehicles t hat require a
large amount of petrol. Computer technology is used to ma ke vehicle
exhausts more efficient and less polluting.
Additio nally, the government supports transport initiatives such as
bus lanes and cycle ways to encourage people to use alternative
forms o f transport. In some cities, such as Lo ndon, congestion
charges are used to try to reduce the number o f vehicles travelling
into the city centre. In London, the charge in 2016 was £1 1.50 a day.
Ma ny UK cities have ' park and ride' schemes. Cars are left in huge
car parks on the outskirts of ci ties and a frequen t cheap bus service
transports people to and from the city centre.
Figure 1.20,6 Cycl•sts do not have to pay
the congestion charge ·n
London
Ecosystems
Wh at is an ecosystem ?
LEARNING OUTCOMES
• Understand the defin tion of
an ecosystem.
• Understand how nut(ents are
recycled ·n an ecosystem.
• Understand the iwportance
of clima te and so'ls in the
developmen t of ecosystems,
An ecosystem is a community of plants and wildlife together with the
environment in which they live. This includes the soil and the atrrosphere.
All the different aspects (components) of an ecosystem interact \,vith
each other and often depend on each other for their survival.
It is possible to identify living (biotic) and non-living (abiotic)
components of an ecosystem . Living components include plants
and animals, whereas non-living components include rainfall,
tempera ture, rocks and soil.
Ecosystems can be small scale, such as a freshwater pond (see Figure
1.21 .1) or coral reef, or they can be large scale, such as a tropical
rain forest or desert. l arge-scale global ecosystems are called biomes.
Pond margin- plenty Of
oxygen and light here.
Plenty of shelter for the
plants, insects and
small animals to eal
Energy from the Sun
Pond surface - there is
plenty Of light and oxygen
here Animals breathe
~ ragonfly
through their gills, lungs
or skin.
~ Marsh
Reed mace
marigold
(bulrush)
Above pond surface - birds
and animals breathe oxygen.
Food is found in or on the
Kingfis~
water or in the margins.
Heron
beetle
~ Dragonfly
nymph
a
Water flea
Midge arvae Tadp;:S
~ Predatory fish
(e.g. perch)
Small fish ~
(e.g. stickleback)
Pond snail
Rat-tailed maggot
aterworrn
Mid water - animals breathe
through gills or skin. Fish are
the main predators. Food Is
found on the surface or on the
pond bottom.
Flgure 1.2 1, 1 Freshwater pond ecosystem
One of the most importan t
featu res of an ecosystem is the
constan t recycling of nutrients
(plant foods). Look at Figure
1.21.2 and notice the following
featu res:
• The Sun is t he source of energy.
water boatrnan~_..:"":la
::;te::;rl~ily~~ A:,;lg~ae:Ji~.,..
~q
~~i~~~
How are nutrients
recycled in an
ecosystem?
Key
Habitat
Pond bottom - little oxygen or
light. Plenty of shelter (rotting
plants and stones) and food
on the bottom. Decomposers
and scavengers live here.
• Energy from the Sun is
converted into usable energy
(carbonates) by producers
(plants) through the process of
photosynthesis.
• Energy is then passed on through
being eaten by consumers.
• When the producers and
consumers die, they decompose
and fungi and bacteria return
the nutrients lo the soil.
• Plants (producers) make use of
nutrients ·n the soil to help them
lo grow.
The importance of
climate
Rainfall and temperature affect the
types of ecosystems that exist in
a particular region. f or examp!e,
tropical rainforests are well suited
to hot and vvet d imates. Rainfall is a
source of nutrients for plants, and water is
essential for plant growth and animal life.
Temperatures affect plant g rowth too.
The minimum temperature for pla nt
g rowth is 6cc. In the Caribbean this
means that there is continuous growth
of plan ts as they are not limited by
low temperatu res. High temperatures
together w ith moisture speed up
decomposition, which explains w hy
fallen leaves decompose rapidly m
tropical enviro nments.
Given a source ol energy an
ecosystem is sen-supporting
PRODUCERS
- - - .ENERGY
algae, lichens and......_ ,
sunlight
_ , / ' green plants · ~
water and
mineral salts
eaten
\
HERBIVORES - eat plants
CONSUMER_...... CARNIVORES _.d'. _
18
animals ::::::- - eat animals
SOIL
humus and
minerals
\
OMNIVORES - eat plants
~
and animals
die
The importance of soils
decomposition
~
Soil provides material m \,vhich plants
can anchor their roots, as well as
important nutrients to help them gro,N.
Soil is formed from two sources:
DECOMPOSERS . - , , , '
fungi and bacteria
All lnlviduals of the same species = a population The populations
together = the community. The community + the non-living part of
the environment = the ecosystem
1 Mineral ma tter derived from the
\"lea thering of bedrock. In the tropics,
Figure 1.21.2 Nutrient cyd'ng nan ecosyStem
chemical weathering is very effective
in breaking down rock, which explains vvhy
some soils may reach a dep th o f 30 m.
2 Organic material from rotting vegetation.
Organic ma terial decomposes to form
material called humus, w hich in the
Caribbea n often appea rs colourless.
Air
Air + water = 50%;
proportions are variable,
depending an conditions
Mineral
material
25%
Look at Figure 1.21 .3. Notice that soils contain
Organic
water and/or air, together vvith mineral and
material
orga nic ma terial. It is also an importa nt
Water
25%
habitat for earthworms and small insects. The
characteristics of a soil - its fertility (the ease
with \<Vhich nutrients are available to plants),
thickness, colour and texture - depend o n
Figure 1.21 .3 The parts of soil
several factors such as climate, vegetation, rock
type and human activities. 11 can take thousands
of years to form, yet can be washed away by a flash flood in a few
minutes. Such a precious resource needs very careful management.
The tallest trees on Earth,
reaching heigh ts 1n excess of
The importance of biotic conditions
115 m, are the sequoias or
Living orga nisms p lay an important role in the development o f
Ca1ifornian redwoods. They are
ecosystems. Figure 1.21 .1 shows the importa nt relationshi ps that
evergreen trees and are very
exist between the species. Figure 1.21.2 shows the role of o rganisms
long living - some are thought
in nutrient cycling w ithout which an ecosystem would collapse.
to be 1,200-1,800 yea rs old!
Before logging and widespread
Huma ns also play an importan t part. Those tha t live nearby often form
deforestation, they used to be
an important part of natural ecosystems, managing them to supply
\,videspread along 1he coast of
useful products. Many natural ecosystems are fragile and can easily
California, USA.
be ha rmed . For example, a coral reef can be severely damaged by o il
pollution or agricultural chemicals. For this reason ecosystems need to
be managed carefully to preserve them for future generations.
Tropical rainforest
biome
Global location
LEARNING OUTCOMES
• Understand the distributon
and climate of the 1ropical
rainforest.
• Understand the characteristics
of vegetation and soils n the
tropical rainlorest.
The tropical rainforest is the most productive natural ecosystem
in the vvorld. An estimated 40 per cent of the world's species of
plan ts and animals live in the rainforest. It covers an area of some
375 million hectares and 5 per cent of the world's land surface.
Look at Figure 1.22.1. Notice that tropical rainforest stretches
across the •Norld from Sou1h America, through parts of Africa and
into South East Asia. The densest areas of rainforest lie between
1 O degrees north and 10 deg rees south of the Equa tor.
---
- -
~
y
,,..
Tropic of Cancer
...
'
r;r·
...
•
..
...;,.
-""-
Equator
', (}
Tropic of Capricorn
-
~.,
~
"
Equatorial rainforest
Fl ure 1.22.1 locat'on of the tropical rainforest b,ome
Currently there is a grea t deal of concern about the threat of
deforestation. Deforestation is causing many natural habitats to be
wiped out and may be having an impac1 on the world's climate and
on global warming .
Climate
The climate in a tropical rain forest is, as the name suggests, warm
and wet. Throughout the year the temperature averages about 2 7°C
and it changes little from mon1h to mon th. Rainfall totals are high,
usually 1,000-2,000 mm per year, and rain fall occurs th roughou t the
year.
Fig ure 1.22.2 shows the climate graph for Zamboanga, Philippines.
• Temperature remains high throug hout the year, hardly changing
from mon th to month.
• Rain fall is also high throug hout the year, although there is a wetter
period from IVlay to December. October 1s the 'Nettest month with
an average of 142 rr: m of rain .
Soils
The so·ls in tropical rainforests are surprisingly low in nutrients
considering the lush vegetation they su pport. There are several
reasons for this:
• IVlost of the nutrients are fou nd at the surface where dead leaves
decompose quickly m the vvarm and wet conditions. Once relea sed
they are quickly absorbed by the plant roots so do not enrich the
soil.
• The plants are 'Nell adapted to absorb these surface nutrients
quickly through their shallow roots.
• Fungi growing on roots also hel p to transfer nutrients directly to
the growing plants.
• Heavy tropical downpours quickly dissolve and wash avvay nutrients
through the soil - this is called leachi ng (see Figure 1.22.3).
I
30
I
I
I
o
~
E 25
~
.,
''
.3 20
'
~
~
E
-'...,=
.,"'""
.'t
~
-
-E
.
E
•
--
µ ri:~~
,- -
'
I
--
'a;
C
.§
150
too l
50
J F MA M JJASO N D
0
Months
Figure 1 .22.2
t
Climate graph for
.
Zamboanga. Ph,hpp nes
• • •
There s great competition for
light in the canopy. It is survival
of the fittest! S-ome t rees have
leaves vvith ilexible stems so that
they can twist and turn to follo\,v
the movement of the Sun during
the day. In this ~Vay they are able
to rnaxim1se photosynthesis and
grow at a more rapid rate than
other trees.
Vegetation
The climatic conditions (warm and wet) are ideal for plant growth,
which explains the lush vegetation found in equa torial regions.
One of the main features of a tropical rainforest is the layering
(stratification} of the plants and trees.
Top canopy
Here the very tallest trees (called emergents) can be found, often
reaching heights in excess of 40 m. These fast-growing trees
outcompete other trees to reach maximum sunlight. Many birds and
insects live in this unique habitat.
Middle canopy
This is the main canopy of the rainforest, forming a dense green
cloud-like 'top' to the rain forest. Some 90% of the vvildlife rves in this
layer, including most birds, mammals like sloths and many species
of monkeys. Specialist pla nts such as epiphytes (plants that can
absorb nutrients directly from water and air) and lianas (vigorous
creepers rooted to the ground far below) are found here. The canopy
intercepts up to 80 per cent of the rain falling on the rainforest and
70 per cent of the light.
Lower canopy
This extends between 5 m-10 m from the forest floor and mostly
comprises small trees and saplings. vVi th limited sunlight, the
vegetation is more open.
Shrub and ground layer
Conditions here are very shaded, apart from \'Vhere fallen trees have
enabled shafts of sunlight to penetrate through the dense canopy
above. Shade-loving pla nts such as small ru bber and S\'Viss cheese
plants are found here, along with some ground cover plants. Wildlife
here eats fruit and seeds from the litter.
Rainforest plan ts have become \'Veil adapted to living in an equa torial
clima te (see f igure 1.22.5).
Figure 1.22.4 An example oi cauhf orous
uee, the cacao tree
• Trees have smooth bark on their trunks - the lack of frost and fire
means that they do not need thick protective bark.
• Taller trees, typically the emergent species, have wide buttress roots
to provide extra stability.
• The warm and wet clima te mea ns that there is no seasonal leaf fall,
so t rees grow and shed leaves throughout the year.
• Tree leaves tend to be leathery in texture to resist the strong
sunshine. They have a drip tip to help them shed water quickly after
a tropical dov,1npour.
• To promote productivity, flowers and fruit grow directly from trunks
and branches of trees - t his is known as cauliflory (see Figure
1.22.4). The seeds of emergent trees are light and fluffy, enabling
them to be readily dispersed by the wind that blows above the
main canopy.
Nutrient recycling is very importan t in tropical rainforests. The vvarm
and vvet conditions promo te very rapid decomposition by fungi and
bacteria, and the rapid take up by fast-gro\<Ving plants. This accounts
for the relative low levels of nutrients in the soil. Heavy rainfall
can remove nutrients from the soil (leaching). The vast maJority of
nutrients are stored in the biomass (living matter, particularly pla nts).
Many leaves have
flexible bases so
that they can turn
Trees are
to face the Sun.
evergreen since
They also have a
there is no dry
Fast-growing trees, such season or distinct drip tip to allow
as capoc, out-compete period in which
the heavy rain to
other trees to reach
leaves are shed. drip off theleaf.
sunlight. Such trees
are called emergents.
Water drips
off leaves
~-
45
40
35
15
->
. , C.
10
;,: c:,
c:, C:
.... "'..,
-E'.,
:c:
5
I
Shrub layer
and ground layer
Thin, smooth bark on
trees allows water to flow
down easily.
Massive ridges, or buttresses,
suppor t the base of the tall trees and
help transport water. They may also
help oxyger\icarbon dioxide exchange
by increasing the surface area.
Plants called epiphytes can
live on branches high in the
canopy to seek sunlight they obtain nutrients from
water and air rather than soil.
Lianas - woody creepers - are
rooted to the ground but carried
by trees into the canopy where
they have their leaves and flowers.
Figure 1.22.S Stratification and ye,getation adaptationsIn a tropical rainforest
'.
·.
59
--
'
Positive and negative
impacts of human activities
in tropical rainforest biomes
LEARNING OUTCOME
Human activities can have positive and negative impacts on tropical
rainforest biomes.
• Understand the positive and
negative impacts o f huma n
activi ties in tropical rainforest
biomes.
Positive impacts
Many people believe that deforestation should be stopped. Indeed ,
there are many good reasons to support this poin t o f view. However,
the economies of countries in the tropics, including t he Caribbean,
often depend to some extent on forest products and gain some
benefits from deforestation.
If the solution is to avoid placing a
ba n on deforestation, then it has to
involve sustainable management
so that forests are utilised bu t
protected for future generations.
This involves the protection of virgin
rai nforest and careful ma nagement
of commercial operations. Trees
need to be replanted and illegal and
unregulated deforestation needs to
be outlawed (see Figure 1.23.1).
Sustainable management
in Guyana
Forestry is extremely im portant in
Guyana. Timber produc1s account
for 5 per cen1 of Guyana 's gross
domestic produc1 (GOP) and the
industry employs around 20,000 persons. While Guyana still has
almost 75 per cen t of its land area covered by forest, it has seen
significant deforestation since the late 1990s. This is la rgely the
result of demands for commercial agriculture, mining, logging, road
building and fuelwood collection.
Reafforestation
Reafforestation involves repla nting trees. The Guyanese
government has set up a number o f projects using money from aid
agencies such as the World wide Fund for Natu re and the World
Conservation Union. These have ·nvolved replanting local species of
trees that have been cut down.
One example is in the Barima region w here local communities are
growing Euterpe oleracea, a type of manicole palm, to be repla nted
in local forests. Palm hearts from Euterpe oleracea palms supply a
.'
U5$2 million export canning industry. It is the most important
non-forest product in nort h-west Guyana.
lwokrama Project
The lwokrama Project is a conservation and research project in central
Guyana, set up in 199610 promote the sustainable use of tropical
ra 'nforests. It has become a living natural laboratory for sustainable
tropical forest management and research into global warming.
There are also opportunities for ecotourisrn in the forest, w hich
enable tourists to learn about the forest ecosystem. The rain forest
here is incredibly nch in vvildlife, w ith over 1,500 species of flowers
and 400 mam mals. The region's wa ten,vays are home to the world' s
highest recorded d iversity of fish species. Aerial \'Valkways have been
constructed (see Figure 1.23.2) to take visitors high into the canopy
where the bulk of the plants and animals live.
lwokrama is home to several of
the world's largest and rarest
creatures on Earth, fncludlng
the green anaconda, the \'VOrld's
largest snake that can grow to
9 m in length. Other creatures
inc ude jaguars, vampire
bats, eag'es and t he bone ess
arapaima fish that can g row to
3 m in length.
In ad dition 1o research and tourism, forest products such as timber,
honey and tro pical fish for aquariums are being exploited sustainably
to earn money to support the local communities.
Forest Stewardship
The Forest Stewardship Council (FSC) is leading the way in promoting
sustainable management of tropical rainforests. It awards a
certificate to companies that have demonstrated enviro nmentally
friend ly practices, such as low-impac1 logging and reafforestation
prog rammes. Consumers of limber are, increasingly, only buying
wood that has the FSC stamp.
In 2006, the Bari ma company's forests in the \'Vest of Guyana
received 1he FSC certificate. However,
just nine months later, in 2007, the
certifica1e was suspended when
a number of irregu larities were
d iscovered . This is a major blo\,v to
both the co rr pany and to Guyana .
Satellite monitoring
In 2008, the Guyana Forestry
Commissio n announced that it
would be using satellite tech nology
to monitor its tropical rainforests
and check for signs of illegal
logging. Using satell ite images, it \'Viii
be possible to digitally tag timber
and track its movements. The project
is part funded by the Japanesebased International Tropical Timber
Organisation.
Negative impacts
Deforestation can lead to economic
benefits as resources are exploited
F1gure 1.23.3 lov,.r impact logging in lwokrama
CASE STUDY
Flooding n Haiti' (2004)
In 2004, Hu rricane Jeanne caused devastating floods, killing over
3,000 persons. Over 330 mm of rain fell in just a few hours.
The scale of the floods was blamed on many years of
deforestation. The lack of tree cover and the very thin topsoils
were unable to store water, resul ting in rapid surface run-off and
flooding.
In the past, 98 per cent of Haiti \'Vas forested . Much of this was
cleared to make \'Vay for sugar plantations and to provide fuel for
the sugar mills. Valuable mahogany was shipped to Europe to be
made into furnitu re.
Recently, rapid population growth and increased poverty have led
to people chopping down trees to make and sell cha rcoal. The
loss of trees has also caused \'Valer tables to fa ll, creating water
shortages for farmers.
and land is used for commercial
farming . However, the long-term
negative impacts of deforestation
tend to outweigh the positives.
Impacts of deforestation in
the Caribbean
Increased flood risk
The removal of forest exposes the
soil to the full force of the tropical
storms that hit t he Car'bbean.
Without the umbrella effect of the
trees, water flows quickly over the
ground surface into rivers, and
floods often result.
Soil erosion
No longer protected by forest, the thin
topsoil is easily eroded during heavy
rainstorms. Deep gullies form and the
land becomes useless for farming.
Rivers become choked with sed·menl,
increasing the flood risk downstream.
Soil exhaustion
Figure 1 .23.4 Hasians try to fix their homes a•ter a flood destroyed ,heir
houses during a storm
Tropical rainforest soils lea k nutrients
and they can quickly become
exhausted if used intensively for
farming. They are then even more
likely to be eroded by wind and rain.
Damage to coral reefs
n Jamaica, young t rees are cut
down to make yam sticks. These
are used by farmers to support
yam vines so that they produce
larger tubers. An estima ted
15-45 million yam sticks are
used by farmers each year.
Sediment washed out to sea following
heavy rainfall can lead to sedimentation, caus•ng coral to die. The
clouding of the normally clear tropical vvaters reduces sunlight and
increases stress on the organ·sms of the coral reef. Scientists believe that
reefs in Jamaica. the Dominican Republic and Puerto Rico are all at risk
from sed imentat·on caused by deforestation.
Decline in aqu ifers
Wa ler stored in rocks below the surface forms underground reservoirs
cal led aquifers. These are extremely important sources of \'Valer in
the Caribbean and many farmers draw water from wells lo irrigate
their crops.
The presence of trees retai ns water on the la nd and enables it to
soak slowly into the soil and the rocks. When trees are cut do\<Vn,
the \<Valer tends to flow quickly over the surface and less filters
downwards. This causes the water table to fall. Rivers and wells dry
up as a result and water shortages are caused.
Ecological damage
The loss of habitats and subsequent reduction in biodiversity is a
major concern in the Caribbean's rainforests. A number of endangered
species, such as 1he Puerto Rican parrot, are under threat. Coastal
forests are importan t breeding grounds for Hawksbill turtles (see Figure
1.23.5), and these are under threat from deforestation in Guadeloupe.
Tourism
Tourism is an important source of income as many people are attracted
by t ropical rainforests. Damage and destruction will have a nega tive
effect, with tourists deciding to visit rainforests elsewhere in the \<VOrld.
Global impacts
Tropical rainforests act as huge carbon sinks. That 1s, they absorb
carbon from the atmosphere and hel p to reduce the build up of
greenhouse gases. If ra inforests are destroyed, less carbon will be
absorbed and the greenhouse gases will become more concentrated
and effective. This could lead to increased global warm ing.
An addi tional problem is that when trees are cut do\<Vn and burned,
carbon is released back into the atmosphere.
/ CASE STUDY
I Deforestatio.n
n Jama,<c~
Causes of deforestation
In the past, most of Jamaica was covered by
rainforest. Today, there are only fragments of
forest in Jamaica's remote and moun tainous
interior. Over 75 per cent of original rainforest
has been lost. The main causes of deforestation
have been:
• baux·te mining and the construction of access
roads
• commercial agriculture, particularly coffee
plantations
• tourist developments around the coast
• logging
• charcoal burni ng.
Impacts of deforestation
Deforesta tion has had several impacts:
• Exposed soil is no\<V much more vulnerable to
soil eros:on and landslides following heavy
rain. In 1988, torrential rain associated wi th
Hurricane Gilbert caused widespread flooding
and loss of life, much of which was bla med on
deforesta tion.
• Sedimentation Is a major cause of damage to
coral reefs. This is caused by loose soil being
swept out to sea following heavy rainfall.
• Rainforests help to retain water during dry
periods. Deforestation has led to water
shortages and some rivers have dried up.
• Species diversity has decreased as forests have
been cut down.
• Trad1t1onal lifestyles and knowledge about local
plan ts and their medicinal uses is being lost.
Soil
LEARNING OUTCOMES
• Understand the man
consti tuents o f soil,
• Understand the factors
affecting the development o f
latosols.
Soil can be defined as a mixture of minerals, o rganic matter,
gases, liquids and organisms that together support life on
Earth . Put another vvay, soil 1s ' the stuff that plants g row in' !
(See Figu re 124.1.)
There are five main constituents of soil:
• Inorganic (mineral) matter - this is derived from weathered rock
or sediment (the parent material). It provides the physical bulk of
most soils, providing an anchor for plant roots. Wea thered minerals
release important nutrients or plant foods. This process occurs
rapid ly in tropical regions such as Lhe Caribbean, promoted by the
high tempera tures and rainfall ,
• Organic matter - this is rotted (decomposed) vegetatio n t hat
adds bu lk and cohesion to the loose rock material. It provides
important nutrien ts for pla nt g rowth and also helps to retain
moisture 1n the soil.
Trop•cal soils are the deepest
soils ·n the world, up to 30 m
deep. This is because the
high temperatures and high
rainfall crea te ideal conditions
for chemical weathering. The
climate is also idea fo r fungi
and bacteria which enable
dead vegeta tion to be rap·d,y
decomposed.
• Gases and liquids - soil con tains air pockets which may contain
gases or \'\la ter, both of which are important in soil formation and
in maintaining healthy growing conditions for pla nts.
• Organisms - biota such as earth,,vorms are very important in
mixing a soil, particularly in dra~ving down surface litter into the
topsoil. Fungi and bacteria are also importan t in soil formatio n,
especially in the decomposition of dead vegetation.
Figu re 1.21.3 page 55 shows the main constituen ts of soil. Notice
that air/water accounts for 50 per cent of soil.
Latosols
La tosols are deep soils that typically form ·n tro pical rainforest
environments. They are characterised by being red in colour due to
high concentratio ns o f iro n and aluminiu m. They
are generally not very fertile.
Figure 1.24.2 shows a typical latosol soil profile. It
describes the main characteristics o f the sod and
identifies some factors affecting its development.
Flgure 1.24.1 Soil crumb structure
..
• Climate - the warm and wet climate causes rapid
chemical wea thering o f the parent material,
accounting for the grea t depth o f the soil. The
high rainfall leads to water draining through
the soil, dissolving minerals such as iron and
redepositing them further down. As we have
seen, this is called leaching (see f igure 1.22.3,
page 57). It accoun ts for the low levels o f fertility
and the reddish colour o f the lower soil horizons
(layers). The ch mate also promotes decomposition
as fungi and bacteria thrive in these conditions.
• Vegetation - the lush rainforest vegetatio n provides plenty of
dead o rganic matter to be decomposed. Although this adds large
quantities of nutrients to the soil, the plan ts quickly absorb them
and leave the soil impoverished and relatively in fertile.
• Biota - many o rganisms thrive in the soil' s warm and 'Net
conditions. They help to mix u p the nutrien ts, ma king them
availa ble to the plants. These conditions are ideal for decomposers
such as fungi and bacteria, w hich release nutrients from ro tting
vegetation.
• Wa ter - water drains rapidly t hrough soils, dissolving and carrying
away nutrien ts (leaching), and causing the soils to be relatively
infertile.
F = fermentat'on
Thick
H• humus
Jitter layer --,_ .,.
Th!n-1 o'.a~
humus fayer
0 hori zon
A horizon
- mlneols
Q)
Rain washes
Iron and
aluminium
!
wa.shed out
c;ompOU'lOS
downward
B horizon
- mlne,rals
@
washed In
Sol's depth
can reach
30 m
Yt11ow1,.,i .., _
SUMMARY QUESTIONS
C hori zon
1 What s soi l and hO'N does
- rock.
·1 form?
bre,a~·ng
down to
maiite so.I
_,_._ .
-
ciot- ► ·~~~-..
iii ~
.., - "'> ~' ~ @
-·
~
~
Throughnow of
sonwater leads
to ossof
30m
de.0th
r,utr:ents
Figure 1.24.2 Latosol so I pro'ile
Adapted from D 1Naugh (2009) Geography: An Integrated
Approach, 4i h edition, Nelson Thornes p. 318
2 Draw a s"mple d iagram
to describe the main
characteristics and processes
responsible for the formation
of latosols.
The hydrological cycle
Wa ter is the most precious resource on Earth. Without water 1he
Earth would be a dead planet. Water is constantly on the move,
being recycled between the ocean, the land and the atmosphere. This
is called the hydrological cycle (see Figure 1.25 .1).
LEARNING OUTCOMES
• Understand the hyd ro logical
cycle and t he processes of
evaporation, condensa tion
and preclp tation.
Notice 1ha t the hydrological cycle involves stores (e.g. oceans
and ice) and flows (e.g. groundwater flovv and rivers). There are
three importan t p rocesses in the hyd rological cycle th at convert
water into different states: eva po ration, condensation and
precipita tion.
• Under,tand the dra 'nage
basin hydrolog,ca cycle.
Ice caps and snow
...
Condensation
Precipitation
(snow or rain)
Transfer of water
vapour by winds
--
Freshwater
storage
Saltwater
storage
I
Surface run-off
by nvers
d
sand lakes
0.6% water
stored as
Transfer
(flows)
Lake
Evapotranspiratlon from
water surfaces and plants
Sea
Evaporation
from the sea
7.2% of wortd's,
Figure 1.25.1 The hydro ogical cycle
EXAM TIP
Leans, tl-ie cl.if{tYevcce
betwee..,, pyecipitciti0 .,,
Cl v,,cJ.
COl'\.cl.tVI.SQtt.ov,, Cl v,,cJ.
be J>Yt pa yecJ. to give civ.
exa""-ple of eacn.
• Evaporation - the conversion of water
liqu id into wa ter vapour. Evaporation is
most effective in sunny conditio ns w hen
the air is warm and d ry and w hen 1t is
mov,ng over the surface (v11ndy). Under
these conditions vva ter is absorbed by
the air and converted from a liquid to a
gas - w ater vapour. Evaporatio n requires
energy, commonly in the form of heat from
the Sun . Most eva poration occurs over the
oceans.
• Conden sation - the conversion of wa ter
vapou r (gas) into \'\later liquid. When air
is forced to cool, either by trave'ling over
a cold grou nd su rface (e.g. ice) or \'\/hen
it rises, the air contracts and is no longer
able to hold so much water vapou r. ~Vhen a
critical temperature (d ew point) is reached,
the air becomes saturat ed and the wa ter
vapou r begins to be converted to wa ter
d roplets. This is condensatio n. The water
d roplets suspended in the air form cloud s
o r, 1f close to the grou nd, mist and fog.
Condensation can be seen in homes on
glass windows, o n the outside of a glass of
ice water or other cold liq uids, or inside ca rs
if warm moist air is in contact \'Vith a cold
surface.
• Precipitation - the transfer of water from the air to the g rou nd.
When 'Na ter droplets can no longer rema in suspended in the air
they usually fall to the g round as rain . Other forms of precipitation
include hail, snow and sleet (a m,xture of rain and sno\'V) .
Drainage basin hydrological
cycle
• over 2oo m
100-200 m
r~-U
~d~~~:,
A drainage basin is an a rea of la nd
d ra ined by a river a nd i1s tributaries
(see Fig ure 1.25.2).
1
The movement of 'Na ter 1hrough
a d rainage basin is shown in
Fig ure 1.25.3 . This is called the
drainage basin hydrological
system. Notice tha t there are seve ral
s tores, t ra nsfers and outputs within
the system .
Mainrlver ffows - -,...._----- - - - - - ' ,
Inagen&ralty
So.rce01
Source ot.
souttlertydq matnRIV&rX
small~1ver Y
11
t;:~~~:~ 1
1
lllles Is the
'
,
~
<1>
I drainage baSin l ,
I ofRlverX
I
•-------"
~
'
/"
x."
\
(I
Tributary
to River X
'1 +N
_,/
{Confluence
1
v·lthRlverY
•
- R,verY /
River X)
_,.,,,
,,
' ,,
..__......._
',,
,~
sea
f--Watershed lorming
/
the boundary of 1he
drainage
basinand
1
f
adjacent basins
Mouthof Rivet X
O
200 km
Input
Evaporation
-
[ Transpiration
Spring
Unsaturated
rock/Soll
[ Infiltration J
·1.vaie;liible--.
Soll molsl!Jre
---
I
Surface run,ott
(overland flow)
· (~~-~~
Throughflow j
1 Percolation l
l
-.
··~ ..,···-
Aquifer
Groundwater
Precipitation: any source of moisture reaching theground.
e.g. rain, snow, frost
Interception: water being prevented from reaching the
surfaceby trees or grass
Surface storage: water held on theground surface.
e.g. puddles
Infiltration: water sinking Into sari/rock fromthe
ground surface
Soll moisture: water held In the soil layer
Percolation: water seeping deeper below thesurface
Groundwater: water stored In the rock
Evaporation: water lost from grouncttvegetation surface
Fig ure
Output
~
·~··············l ···...... -.·····Saturated
rock
...
.......
[ Evaporation
Storage
Flow (transfer)
1.25.3 Dra,nage basin hydrolcg.cal system
.., ......······
River carrying water
to a lake or the sea
-------......
··-.
'
··- ......········
[ Groundwater How
·•··· ... ... ···-
I --------•
Transpiration: water lost through pores in vegetation
Surface run-off (overland flow): water flowing on
top of theground
Throughllow: water flowing through thesoil layer
parallel to !he surface
Groundwater flow: water !lowing through the rock
layer parallel to the surface
Water table: current upper level of saturated rock/
soil where no more water can be absorbed
Aquifer: saturated rock forming an underground water reservoir
Spring: water emerging onto the ground surface from
underground
Drainage system fluvial processes
Fluvial processes
LEARNING OUTCOME
• Understand the fluv al
processes of transportation,
erosion and oeposi tion.
Most of a river's energy is used to overcome friction . Only about
5 per ce11t is used to transport sediment downstream or erode the
river's banks and bed.
One of the most important factors affecting river processes is velocity
- the speed of flow. While velocity increases slightly downstream, it
does vary considerably w ithin the river channel i1self. It also va ries
from day to day and betv,een the different seasons. A 1orrential
downpour can lead to a sudden increase in river velocity, as can
snowmel t in the late spring or early summer in countries that
experience \<Vinter.
Transportat ion
There are four processes by which a river's sediment, or load, can
be transported downstream. Notice in Figure 1 .26.1 that the larger
particles tend to be rol led along the river bed whereas the smaller
(lig hter) particles are more easily picked up and suspended. You
can see how important velocity is in affecting w hich particles are
transported by which process.
RIVER FLOW
• •
TRACTION
Rolling stones along
Ille bed. (This needs
Ille most energy.)
Figure 1.26.1
. .. .
•
SALTATION
Sand-sized particles
bounce along the bed
In a 'leap frog'
movement.
•
SUSPENSION
Silt and clay-sized
particles are carried
within the water flow.
SOLUTION
S6me minerals dissolve
in the water. (This
needs the least energy.)
Transportation
Erosion
There are four processes of river erosion:
• Hydraulic action - the sheer force of flowing water.
• Corrasion - the scou ring action as rocks carried in the river are
scraped along the bed and ban ks.
• At1rition - as rocks are bashed against each other and are dragged
along the bed, they gradually become smaller and more rounded.
This explains why river sediment tends to decrease in size and
become less angular \<Vith distance do\<Vnstream (see Figure 1.26.2).
EXAM TIP
Particle
size
Iv. AY\. ex,ci..,._,ilA,/,ltco,,., tfO<-<
ci..-e ofl:ev. Aslud to desc..-ibe
A111.d, give ex.ci""-J>Les of
Sj>ecsfi,c fecituyes ,,,., Cl
Yive..-·s COt.<YSt. MA!u
.su..-e tfO<-< cci"" i.LLustrcite
tne feCltures .,,i.tl1 ci weLLLA beLLed dicigyci .....
Distance downstream
Figure 1.26.2 Erosion byattri1ion
• Solution - the dissolving of rocks, such as limestone, ow ng to the
mildly acidic effects o f carbon dioxide being dissolved in the \'\la ter.
Deposition
Deposi tion takes place w hen velocity decreases and the river is unab le
to transport its load . This happens when a river enters the sea or a
lake, \,vhich explains the extensive deposits o f mud in river estuaries
and river mouths. Deposition will also occur on the inside bend of a
meander where velocity is lo,Ner (see f igure 1.27.5, page 72).
In most rivers there is an order o f depositio n, \'Vith coarser
sediment being deposi ted near the source and very fine grained
sediment - silt and clay - being deposi ted towards the river mouth
(see Figu re 1.26.3).
Order of deposition
River source
River mouth
I
I
I
I
Sedimect size
I
I
I
I
Boulders
Cobbles
Pebbles
:
Sand
Silt
Clay
I
I
I
-.. --.. r
>256 mm
.
,' 64 - 256mm ,
2 - 64mm
Figure 1.26.3 Order of deposition n a river
0.0625 - 2 mm
I0.002 - 0.0625 mrrl <0.002 mm
River landforms
LEARNING OUTCOME
• Understand the fluv al
processes of transportation,
erosion and oeposi tion.
River valleys
While all rivers are unique they often d isplay similar characteristics and
landforms from source to mou th. In 1he upper course a river often
carves a steep-sided V•shaped valley (see f igure 1.2.7.1 ). Notice that
mass wasting is an important process aHecting the shape of the upper
slopes o f the valley. Harder outcrops of rock ju1 into the valley forcing
the river to flow around them. These are called interlocking spurs. The
river itself, which is usually narrow and shallow, tumbles over the rocky
river bed to form swirling eddies and whirlpools.
Potholes
KEY TERMS
Mass wa sting: the downslope
movement of rock and/or soil
1n response to gravity, usually
involving sl ps, s ides and flows.
The swirling action o f 1he vvater ma river' s upper course o ften
forms hollows or depressions 1n 1he river bed called potholes. They
are formed mainly by the process of corrasio n, when o ne or more
pebbles g rind ou t a hollow as t he \'\la ter swirls round and rou nd ,
rather like the action of a d rill!
Rapids
If the river bed is uneven, possibly O\'Ving to alternating bands of
hard and soft rock, a series o f small s1eps called rapids may form .
Figure 1.27, 1 A v~shaped valley 1n Dom inica
These are rather like m 'ni-waterfalls and they often provide exciting
challenges for canoeists. There are many examples of rapids in 1he
Caribbean, for example at Kurupukari on the Essequibo River in
Guyana .
• •
With a fal of over 225m,
Kaieteur Fa Is in Guyana is one
of the ,,vorld's tal est single-drop
,,va terfal 's. The ta' lest ,,vaterfall
in the v,or d is Angel f a Is in
Venezuela, whrch drops an
incredib e 979m .
Waterfalls and gorges
A waterfall is a sudden 'step' in the long profile o f a river. It
often forms when a river crosses a relatively hard band o f rock
(see Figu re 1.27.2). It may also form w here a river flov,s over a
cliff or escarpment.
• Erosion of the weaker rock beyond
leads to the forma1ion o f a step
over which the water plunges.
• Over a period of thousa nds of
years the ,,vater erodes a deep
plunge pool benea th the waterfall.
• Corrasion and hydraulic ac1ion
slowly undercut the waterfall,
resulting in the forma tion of an
overhang.
I
so1~er, less'llSls~nllcck
7
°"""IIIO
· O,..,ar<1
I -,.-~,: CO.'a?stl
I
Plo,01 PGOI
• Unable to hold its own ,,veig ht,
the overhang collapses and
the waterfall retreats upstream
forming a steep-sided gorge .
Figure 1.27 .2 Formation of a waterfall
Figure 1.27.3 Kaleteur Fa.ls, Gs;-ana
Figure 1.27.4 Angel F,;lls, Venezue 1a
LEARNING OUTCOMES
• Understand the charactefistics
and format o n of meanders,
oxbow lakes and bra ding.
• Understand the charactefistics
and format on o f floodp ,ains,
levees and deltas.
Meanders
A mea nder is a sweeping bend in a river. It is a common f eature of
a river m its middle and lower course. The land on either side of a
meandering river is usually fla t and forms the river' s floodplain .
Look at figure 1.27.5, which shows the main fea tures of a meander.
• Highest velocity occurs around the outside bend of the meander.
• Erosion occurs on the outside bend, vvhere velocity is high, to form
a river cliff.
• Deposition occurs on the inside bend, vvhere velocity is low, to form
a point bar (sl ip-off slope).
Floodplain
A- - - - - - - - - B
Slowest Fastest River
current current cliff
~-- -
-)
_..
~
~
\:
\
~
Sand and shingle
deposited
Bank w,11
, eventually
'icollapse
Outside bank
is undercut by
lateral erosion
Figure 1.27.5 Meander feat"res
EXAM TIP
Gl.uesti.o....,s o"" ""'-t""'-ciers
""'cl oxbow lG!)us "Ye veyi::,
co""'-""'-0 Y\, i.t,\, f,/(/;I Y\o\.i.""" ti OVI.$ •
MG!ke SKYe 1::JOK C,/;IY\,
clescycbe tl,e stG1ges fro..._
tvie cievelo-p>¾e...t of "
v><.ea"'-cieY to tvie fon,,,,,ati.ovc
Pf tl,e CIA.t-off.
Over a long period o f time the lateral (sideways) erosion on the
outside bend, together \'Vith deposition o n the inside bend, causes
the meander to move across the floodpla in. This is called meander
migration.
Oxbow lakes
Oxbow lakes are horseshoe-shaped la kes tha t are found on river
flood plains d ose to a mea ndering river. They are former meander
bends that have been cut off by the river during a period of high
discha rge or flooding.
Look at Figure 1.27.6.
• Figure 1.27.6a. Notice that the meander is almost doubling back
on itself.
• Figure 1.27.6b. As erosion ta kes place on either side of the
meander the meander 'neck' gets narrower.
• Figure 1.27.6c. During a flood the water breaks throug h the
meander neck, cutting off the old meander. Deposition at the side
of the new channel gradually seals off the old meander, which nov,
becomes an oxbow lake.
The term 'oxbow' comes from
the shape of the wooden yoke
that traditionally fits on the neck
of an ox when it is pulling a
plough.
Once formed, the oxbow la ke will slowly become silted up and it will
eventually dry up altogether.
a
b
C
Meander loop
bends Increasingly
Outside of bend
wrth river cliff
Oxbow
lake
\~~
-----....
I
Inside of bend
~ with slip-off ; 1
,slope
/, /
---::::-----+Fastest current on
outside of bend
\
f
Slowest current \
on Inside bend
-------
~
Lateral erosion
Deposttion
Fastest current
Meander
neck
....______
...._ - - - - -1
---.:::::::::;i..._-=-::..::..-:_- _--+t1-::::::::::::::=~
► __,...
_,
Neck gets
narrower
Agure 1.27.6 Formation of an oxbow lake
Braiding
A braided river is one that is divided into several smaller cha nnels,
separated by islands of deposited sed imen t (see Figure 1.27.7).
Braiding occurs most commonly in rivers that have variable rates of
discharge and carry large amounts of sediment. Seasonal changes
m river discha rge occu r as there is limited rai nfall in the dry season
and greater rainfall in the \<Vet season. During intense and prolonged
rainfall in the wet season the river is able to transport larger gravels
and boulders. Af1er the intense rainfall, the discharge is reduced and
the heavier bedload is deposited on the river bed. These gravels and
boulders form obstacles in the path of the sluggish river and cause
more sediments to be deposited. The river oflen splits into several
separate channels and flows around the objects. After some time this
deposited sediment forms river islands, aits or eyots.
Water is taken (abstracled) from several rivers in the Caribbean, which
can reduce their discharge and also cause the bra iding to occur.
River cuts through Uie neck
of land during a time of flood
In Canada and Iceland, many of the rivers are fed by glacial me!twater.
Even though the nvers in
the Caribbean are small, the
variation in d 'scharge produces
some braiding, for example on
the Yallahs River in Jamaica.
• The high volume of discharge during the spring and ea rly summer
(when ice and snow is melti ng) transports a great deal o f sed iment,
pa rticularly sand and gravel.
• However, during periods of lower d ischarge (at night and d uring
the autu mn and winter), heavier sediment is deposited rapid ly,
causing the river to spli t into several separate cha nnels that vveave
around the deposited islands.
Floodplain
A floodplain is an area of flat land o n either side of a river. It is most
extensive in the lower course of a river and is usually found w here the
river is meandering .
Floodplains are largely made o f fine river sediment called silt, which
is very fertile. This explains w hy floodplains are very product've
agricultural areas (see Figure 1.2 7.8). Oxbow lakes may also be found
o n floodplains.
Tv,o important processes operate to form floodplains:
1 Meander migration over thousands of years slowly widens the
valley as erosion at the outside meander-bends nibbles away at
the valley sides.
2 Extensive depositio n o f silt occurs every time the river bursts its
ba nks during a flood. This may ha ppen several times a year.
Levees
A levee is a raised river ba nk. ll is formed w hen the water in the river
channel overtops its banks during a flood (see f igure 1.27.9) .
• As the water overflows, velocity fa lls and coarse sediment such as
gravel and sand are deposited on the river bank.
Gentle
valley side
River flowing above
height of lloodplaln
Flat lloorplain
---~
Coarse material forms
natural levees
Figure 1,27 .9 Cross-section of a river f oodp!a1n
Gentle
valley side
Levee artfficially
heightened and
strengtllened
Layers of silt
deposited during
several floods
• Repea ted flooding, over ma ny years, results in
the gradual raising of the river banks above the
level of the floodplain to form distinct levees .
Distributary
Delta builds up
River banks can be raised artificially to protect
floodplains from flooding. In some parts of
the world, for example the USA, these artificial
embankments are also called levees.
Deltas
A delta is an extensive area of sediment formed by
deposition at the mou th of a river or \'\/here a river
flows into a lake. Look at Fig ure 1.27.10 w hich
shows how a delta is formed.
• A river carries a vast amount of sediment in its
lower course.
• When it meets the sea or flows into a lake, the
velocity decreases rapidly, leading to deposi tion
of l he sed iment.
• Heavier sediment (sand) is deposited first,
followed by finer silt and clay as the velocity
continues to fall.
• Over time, the layers of sedimen t build up to
form ne\,v land. Gradually l he coast extends
out into the sea or the lake.
• Rivers flowing over deltas are often forced
to split into separate channels called
distribu taries . This is because the red uction
in the river's velocity leads to increasing
amounts of deposition.
Fi
River velocity reduces as It
enters the sea: deposition of
progressively finer sediments occurs
ure 1.27 ~10 Format on cl a delta
The delta stretches
approximately 160 km in
each direction (northsouth and east-west).
The River Nile in Egypt forms an excellent
example of a delta as it flows into the
Mediterranean Sea (see figure 1.27 .1 1). This
triangular-sha ped delta is called an arcuate
delt a. The other main type of delta is a bird's
foot delta, w here the distri butaries extend
into the sea, flanked by deposits of sediment.
The Mississippi is an excellenl example of this
type of delta
The Mediterranean Sea is
shallow and has no tide.
It does not have enough
energy to remove the silt.
rt Said
/
•
-A
_svez
}Canal
N
~--'-~
'
The river forms
distnbutaries as
it flows through
the delta.
EXAM TIP
0
km
f
Cairo
Red
100
Sea
The River Nile carries a huge quantity of silt as It approaches the sea.
The silt contains many nutrients, so makes good farmland, and fish
thrive In the nutrienl-Iich water. The silt, which has accumulated
over centuries, forms a flat, fertile delta, which is now a densely
settled area.
Figure 1.27 .1 1 The Nile delta
Coastal system - wave
processes
LEARNING OUTCOMES
• Understand the forl"1at1on of
waves.
• Understand the forma tion
a nd character sties of
constructive and destn,1ctive
waves.
• Understand how waves affect
Caribbean coastlines.
What causes waves?
Waves are most commonly formed by frict ion as the wind blows
over the surface of the sea. They can also be formed by ea rthquakes,
volcanic eruptions or u nderwa ter landslides. These events a re ra re but
can lead to the formation of devastating tsunami.
In 2004, a massive earthqua ke triggered giant tsunami waves that
swept across the Indian Ocean killing some 240,000 persons. In
2011, a massive ea rthquake in north-east Japan triggered tsunami
waves that killed over 16,000 persons a nd disrupted the supply o f
nuclear e nergy to the economy.
What causes waves to break?
The reason why the prevailing
north-east winds are called the
trade winds s because they
were very important in the past
in enabling sea trade to take
place between Europe and the
Americas. Sometimes dust from
African deserts can be blown
a the way to the Caribbean by
these winds.
Look a t f igure 1.28.1. No tice tha t in deep water the surface waves
form part of a circula r movement of wa ler. This explains why there
1s actually very little horizontal movement of 'Na ter in the oceans.
However, look vvhat happens as the waves get nearer to the coast:
• As the sea near the shore is shallow the circular motion of the
\,vaves is interru pted by friction with the seabed .
• The water motion becomes more elliptical (shaped like a rugby
ball).
• The wave grows in height a nd beg ins to topple forward .
• Eventually the wave breaks on the shore. Water moves up the
beach as the swash and then drains back down the beach as
backwash.
The power of the waves when they reach the coast depends o n three
factors:
1 Distance of open water over which the wind has blown. This is
called the fetch . The longer the fetch the more powerful the waves.
2 Strength of the wind. The stronger the wind, the more pov,1erful
the waves.
Top of wave
moves faster
0
Wave becomes more
Circular orbit
elliptical in movement
in open water
"own base of wave
Ftlcllon slows u
Flgure 1.28.1 \'\laves approaching '"" coast
Wave begins
to break
Water from
previous
wave returns
Water rushes
up the beach
--
~
Increasingly
elliplical orbit
•
Shelving seabed
3 Duration of the wind. If strong \'Vinds have
blown over a long period of time, this will
resu It in powerful l'Vaves.
Strong swash:
pushes material
up the beach
- - - - - ~~~ ·)
Constructive wave
(smaller In height)
,··-~~··_
Constructive and destructive
waves
~
Weak backwash 4
little erosion
.,'-'""
.
•
It is possible to identify two types of 1,vaves.
1 Constructive waves
Constructive waves are lo\'V bu t powerfu l
waves that surge up the beach when they
break (see Figure 1.28.2). Their swash is much
more po1,verful tha n their backwash, much of
which percolates through the beach as the
water flows back to the sea. Constructive
waves are created by storms ma ny miles away
from the coast and they travel fast across the
ocean. They are called 'constructive' waves
because they transport beach ma terial to the
top of the beach, thereby 'constructing' it.
2 Destructive waves
Figure 1.28.2 A consm.,ctive wave
Weak swash: llttle
beach-building
Destructive wave
(larger in height)
Strong backwash: scours
the beach, pulling sand and
shingle down the beach
Figure 1 .28.3 A desm..ct\•e wave
Destructive waves are essentially the opposite
to constructive waves (see Figure 1.28.3).
They are taller and tend to crash down on to a
beach rather than surging up the beach. There is little swash but the
backwash is powerful. This leads to the erosion of the lower beach,
hence the term 'destructive'. Destructive waves are usually formed
during local storms that are centred close to the coast.
Winds and waves in the Caribbean
Look at Figure 1.28.4. It shows the winds and waves
affecting the coast of Barbados. Notice the following
features:
• The prevailing (most common) winds (the trade
winds) blow from the north-east.
• East-facing coastlines tend to be affected by highenergy waves. This explains why surfing is popu lar
along these exposed coastlines. It also accounts for
the features of erosion that are formed by these
powerful waves.
• West-facing coastlines are sheltered from the
trade winds and exper" ence less powerful 1,vaves.
Depos'tion dominates, forming wide sandy
beaches. Tourism is popular along these sheltered
coastlines.
Adantic
Ocean
Crab Hill<
7 • _•. \
) Spring
<"
\ Hall
~0
~ Speightstown
~
·-
"'
~u \
.,
North-easterly
_,,,. trade winds
It',/
High-energy
.•
o, / waves driven
Belleplame \
"o , / onshore by
Bathsheba,._ <i.sI 11
prevailing
IJ e trade winds
......
-,::,
.,
--.,
8 A R 8 A OOS
•
Belair
,:;
"'
St Patricks
•
- ...._..:D::.:Istins
.\._.r
Caribbean
Sea
Figure 1.28.4 BMbados: wind and waves
Low HIiis MIS.
LEARNING OUTCOMES
• Understand the processes of
coastal eros·o n
• Understand the processes of
sed ·men t transportation and
deposi tion.
• Understand the characteristics
and format o n of beaches.
Processes of coa stal erosion
There are four processes of coastal erosion:
• Hydraulic action - the sheer force of the waves as they break
against a cliff, causing bro ken rock fragments to be dislodged
(see Figure 1.28.5).
• Corrasion (or abrasion) - pebbles are picked up by the sea and
flung against a cliff. The constant sa ndpapering e ffect o f pebbles
pushed up a nd down a rocky platform by wave action is called
abrasion.
• Solution - the dissolving o f soluble rock, such as limestone.
• Attrition - as rocks ru b aga inst each other they gradually become
smaller a nd more rounded. This process rela tes purely to rocks
coming into contact with o ne another, and is no t about the erosion
of cliffs.
Figure 1.28.5 \+\laves break against the rocks r.ear Devil's Br dge in Ant:gJJa
Coastal erosion is most effective when the waves are powerful
a nd contain a lo t of energy. These waves need to break a t or close
to the foot of a cliff if they are to carry ou t erosion. This expla ins
why erosion 1s active on coasts that have narrow beaches, steeper
u nder.-vater gradients a nd face the prevailing vvinds, such as the east
coast of Barbados.
Sediment t ran sport and deposition
There are many different types of sediment at the coast , including
beau tiful white cora l sand, the more common yellow sand, pebbles
(shingle) and mud. The waves, tides a nd offshore currents constan tly
move this sediment up a nd down t he beach and a long the coastline.
This is coastal transportation .
Look at Figure 1.28.6. It shows the common processes of sed 'men t
transportation . These processes will usually operate at the same time.
moving particles of different sizes. Small particles w ill be picked up
and suspended in the \'\later whereas larger particles will be rolled or
bounced along the seabed.
DISSOLVED LOAD dissolved chemicals
TRACTIONrolling along seabed
SUSPENSION Cilfried in the water
SALTATION-
bounced along seabed
•
.•
..
0
Figure 1.28.61 Sediment movemem
One important factor affecting the movement of sediment at the
coast is the direction of the approaching waves:
• If waves approach the coast head o n, sediment will simply be
moved up and down the beach.
• If the waves approach the coast at an angle, sedimen t will move in
a zig-zag pattern along the beach. This is called longshore drift
(see Figure 1 .29. 7, page 83). It \'Viii o ften result in a build-up of
sediment at o ne end of the beach.
Deposition of sediment occurs when the velocity (speed of flow) of
the water is red uced and the sediment can no longer be carried or
moved by the sea. This occu rs most commonly in sheltered areas, for
example in a bay (see Figu re 1.28.7).
Agure 1.28.7 Par 1atuv1er Bay. Tobago
Coastal landforms
LEARNING OUTCOMES
• Understand the charactefistics
and format on of cliffs and
wave-cut platforms.
• Understand the charactefistics
and format on of head ands
and bays, caves, arches and
stacks.
• • •
Landforms of coastal erosion
Cliffs and wave-cut platforms
•
The 21 m high limestone cliffs
at Negril, Jama.ca are listed
as one of the top ten most
dangerous cliff jumps on
Earth. Chff diving - so met mes
known as 'tombstoning' - s a
popular extreme sport across the
world. However, it is extreme y
dangerous and should only ever
be done by experts. Each year
several 'tombstoners' die or
seriously iniure themselves when
they misjudge the depth of the
water.
Figure 1.29.1 Linle Say, Barbados
Look at f igure 1.29.1. It shows the main featu res associated with a
cliffed coastli ne. Over hu ndreds of years the cliff gradually retreats
and the wave- cut platform at its foot becomes wider. Figure 1.29.2
describes what happens.
• Repeated erosion (hyd raulic action and corrosion) at the foot of the
cliff results in a wave-cut notch.
• The wave-cut notch becomes enlarged, creating an overhang of
rock above it.
•
:.:::::..-.- · · -:.. ··- ...
_ ---..:
..._--
Cliff retreats
V----....
:
~--.J
I
:--._ _
,___.J
---..__,,_;;)
___
,
'
i
'
.
:
J/:
__.,i
.
/
··v
i
--........._ -......J
-
/
..•,i
'
Original
position of cliff
Clttf is undercut
by waves and
collapses High tide
wave-cut pfaiform
Figure 1.29.21 Fom,ation of a •1, ave,-cut platform
:
'
• The overhang of rock collapses,
perhaps following a period of stormy
wea ther, to form a pile of rocks at the
foot of the cl iff.
• The sea erodes away the loose pile of
rocks.
• Abrasion smoothes and extends the
underlying wave-cut platform.
• The sequence repeats itself so that the
cl iff face retreats and the wave-cut
platform becomes more ex1ensive.
In parts of the Caribbean \<Vhere
limestone is exposed at the coast,
solution (chemical dissolving) and wave
action can crea te a low-tide platform.
Unlike a wave-cut platform, it is not
exposed at low tide (see Figure 1.29.3).
Headlands and bays
Headlands and bays are common coastal
features in the Caribbean and elsewhere
in the \,vorld.
• Headland - a section of rocky
coastline that protrudes ,nto t he sea.
• Bay - a pronounced indentation in the
coastline usually found between 1\,vo
headlands.
_,--Visor
Low-tide platform
High tide
Low tide
1 metre
Limestone coast
Figure 1.29,3 A low•tide p atiorm
Relief (metres)
0 0ver500
0 200-500
0 100-200
□ Under 100
• swamp
N
t
0
km
30
~.,,,"'in,.__
Port of Spain
Gulf of
Paria
Montserrat
HIiis
Headlands and bays most commonly
form when rocks of different strengths
are exposed at the coast or \<Vhere
Figure 1.29.4 Relief map ofTr'n:dad and Tobago
alternating bands of high and IO\'V land
reach the coast. Look at Figure 1.29.4
which shows the relief of Trinidad. Notice hO\'V the headlands (points)
and bays on the east and west coast match the high and lo\'V land.
On the north coast, the headlands and bays are carved in the toug h
metamorphic rocks with bays at the mouths of
the river valleys formed along areas of IO\<Ver
resistance.
Caves, arches and stacks
Exposed headlands are affected by po\,verful
erosive waves. There are several distinctive
landforms associated \'Vith the erosion of a
headland, such as sea caves, arches and stacks
(see Figu re 1.29.5). A sequence of events
expla ins the formation of these landforms
(see Figu re 1.29.6).
Headland, for example the Foreland in Dorset, UK 4 Roof of arch becomes too heavy
to be supported and collapses
_.,.,. /
H- 1
\ '
*__,, _. . ,.__ ·
f
Joi~t or fault in
, res,staf:1 ,IOC~ • _
'
, /
-.J
Corrasion and hydraulic
action of waves widens
lhe weakness In the cliff
to form a cave
1
~~
l
•
N'-,;, ~
"
~J
5 A stack is an isolated
portion of the cliff
6 Toe stack ls undercut and
collapses to leave a stump,
which is covered up at
h1
e
3 Waves cut through headland
to form an arch, which is
continually widened at Its base
Figure 1 ,29.6 Arch and stack formation
• Weaknesses in the cliffs, such as joints (vertical cracks) and faults
\,viii be exploited by the processes o f hyd raulic action and corrosion
to form sea caves on opposite sides of a head land .
• Over time the sea caves become enlarged a nd eventually join to
form an arch.
• Weathering and erosion processes enlarge the arch, a nd the roof
gradually becomes thinner.
• Eventually the roof o f the arch col lapses under its own weig ht,
leaving behind a n isolated pillar o f rock called a stack.
• Gradually the stack is eroded until all that is left 1s a low rock
outcrop exposed only at low tide. This is called a stu mp .
Landforms of coastal deposition
Beaches
A b ea ch is a deposit of sand and/or pebbles found at the coast.
Beaches are the most common a nd \,videspread landforms o f coastal
deposition. Sandy beaches are most likely to be formed in sheltered
stretches of coast, where the gentle waves are o nly capable o f
carrying finer sediment. Beaches made of pebbles (shingle) tend to
form a long high-energy coastlines where the more powerfu l \,vaves
can transport larger particles onshore.
Look a t f igure 1.29.8. Notice how a beach has formed in the bay.
This is called a bayh ead beach . Deposition has occurred here
because the waves in the bay have less energy than at the headla nds.
This is caused by the waves being distorted by the shape o f the
coastline - a process called wave re fract ion.
• In the open water, wave energy is spread ou t evenly along the wave
fronts.
• As the \'\laves approach the shore they become distorted by the
shape of the coast.
• This ca uses energy (shown by lines called orthogonals) to become
concentrated at t he headlands to form features of erosion such as
cliffs.
• In the bays, energy is reduced (notice that the orthogonals spread
apart) and sediment is deposited to form a beach.
Wooden groynes slow down
movement and widen the beach
Depletion
ol sand"--
Accumulation
ol sand
Backwash carries
material directly
down the beach
under gravity
\0
I
.-
Direction of longshore drift
"-
0
CThird
position
o BSecond
position
o AFi/St position
01pebble
...._ Waves approach beach at an angle· ~ often determined by the prevailing wind
Figure 1.29.7 Longshore drift
B
Beach
Headland w~h
features of
erosion
Wave
fronts
A Energy concentrated - erosion
B Energy spread out - deposition
Agure 1.29.8 Wave refraction
Wave refraction - waves are
distorted as they enter the bay
Lines of energy
called orthogonals
LEARNING OUTCOME
• Understand the charactefistics
and format on of spits,
tombolos and bars,
Spits
A spit is a narrow finger of sand or pebbles that juts out into the
sea from the land. It is formed when sediment t ransported along the
coast by longshore drift is deposited at a bend in the coastline.
Look at f igure 1.29.9 to see the development of a spit.
• Over time the sediment gradually extends in to the sea at the point
\'\!here the coastline changes its shape.
• Fine muds are deposited in t he very calm sheltered \<Vaters behind a
spi t 10 form mudflats and saltmarshe s.
• The tip of the spit becomes curved to form a recurved tip or hook
O\<Ving 10 changes in the wind and \'\lave direction.
The important thing to remember about a spit 1s that i1 is actual land.
It does not become submerged by the sea at high tide.
Prevailing
posrtions
G) Successive
of thegrowing spit.
wlnd
® The 'hook' forms when
there is a change ln the
® direction of windiwaves.
\
The longest spit in the world is
the 11 Okm long Arabat spit ·n
the Sea of Azov, an extension of
the Back Sea bordering Russia
and Ukrame. There are several
other spits n the Sea of Azov,
some of which are over 30km
long.
in v;rg1nia, USA, the Willoughby
spit in Norfolk 1s said to have
been formed by hurricanes in
the 18th and 19th centuries that
washed up huge quantities of
sand onto the coast.
Headland
Short-term
change in wind
and wave
directio~
Figure 1.29.9 Formation of a spit
Tombolos
Figure 1.29.10 Atomboloconne<tsan
Island to the manland
Occasionally a spit grows away from the shore and becomes attached
to an island (see f igure 1.29.10). This is ca lled a tom bolo. A good
example is Sco11s Head tombola in Dominica. The Palisadoes tombola
just south of Kingston, Jamaica, is a highly complex 13 km tom bolo
that connects several offshore cays. 11 is the site of Kingston's Norman
Ma nley International Airport.
Bars
A bar 1s a long narrow deposit of sand or sh ingle that usually forms
parallel to the coast. There are l\,vo main types of bar:
1 A bay bar is a deposi t of sand or shingle that forms across a
bay, often trapping a freshwater lake or lagoon behind it
(see f igure 1.29.1 1).
2 An offshore barrier bar is a narrow sand or shi ng le deposit
tha t runs parallel to the coast ju st out to sea . It is usually only
exposed at lo\'V tide. A shallo\'V saltwater lagoon forms behind
the bar, topped up at each high tide when water washes over
the bar. Over time the offshore bar may form a long na rrow
isla nd called a barrier beach (see Figu re 1.29.12). The Miami
su burb of Miami Beach in the USA has been developed on
an offshore bar now connected to the mainland by several
major bridges. In the Caribbean, !\'Vo bars along the coast of St
Thomas, Jamaica, enclose a lagoon known as the Yallahs Pond.
1
2
Offshore bar/barrier
Sand moved offshore
from rivers and by tides
Mangrove
forest
/
Barrier beach
agoon
Fi ure 1.29.12 Formaf on o.: a barrier bar and lagoon
Tidal
currents
Drainage patterns
LEARNING OUTCOMES
Drainage patterns
• Understand and recognise the
distincfve dra nage patterns
formed by rivers.
When viewed on a map or an aerial photo, rivers often form
distinctive drainage patterns. Look back to Figure 1.25.2, page 67.
Notice that the river and its tributaries form a pattern similar to the
branches of a tree. This is called a dendritic drainage pa11ern.
• Understand that dra nage
patterns reflect the phys ca•
geography and geology of
an area.
There are three common drainage patterns: dendrit1c, trellised
and radial. They are largely determined by gradient, rock type and
geolog ical structure.
Dendritic
Over 97 per cent of all water
is stored in the world's seas
and oceans. Of the rest, 2.1
per cent is stored as ice, mostly
in Antarctica and Greenland,
0.6 per cent as groundvva ter,
0.1 per cent in rivers and lakes
and just 0.001 per cen t in the
atmosphere!
This tree-like dra'nage pattern develops in gently sloping river basins
with a uniform rock type (see Figure 1.30.1). Streams flow into
each other almost at random. The Caroni River in central Trinidad,
which flov,s over relatively vveak sands and clays, is a good example.
Dendritic drainage patterns are the most common in the Caribbean.
Streams flOwing
dovm a sloping
landscape - ,
Sea
Unllorm
rock lype
Figure 1.30.1
A dendritic drainage pattern
Trellised
Trellised drainage resembles a rectangular grid , with tributaries
joining at rig ht angles. This type of drainage pattern develops
in areas with bands of alternating weak and resistant rocks (see
Figure 1.30.2). Notice that the ba nds of rock have been folded and
are dipping (plu nging) steeply. Tribu taries erode the 'Neaker ba nds
of rock and therefore join the ma in river at right angles. This type
of drainage pattern exists in the Northern Range in Trinidad, where
folded rocks cause tributaries to join the main rivers at right angles.
Tributaries Join
at right angles
Streams pick out
bands ofless
resistant rock and
erode aklng them
Band ofless
resistant rock
Sea
l.e$S
r6$1S~an1
rock
Figure 1.30.2 A ire lised dra,nage pattern
800 m
600 m
400 m
200 m
CARIBBEAN
Ra dial
SEA
Rad ial d rainage commonly occurs w here rivers
flow downhill from a central dome o r mountain
(see Fig ure 1.30.3). In the Caribbean, radial
d rainage is often associated w ith volcanic islands
such as St Lucia, Nevis and Montserra t. Here the
rock type is the same (often a lava flow), so it is
g radient that determines the pattern of d rainage.
Om
Look at t he map of Montserrat o n Figure 1.30 .4.
A radial drainage pattern can be seen \<Vhere
rivers flow away from the volcanic centre
towards the sea.
S:reams drainou1
lromacentral dome
Coik Hill
a,..,.,
,.,,,,,
Rlcti
n
,,._,. . .
.£
/
C'1a11cn
,$iu~
0
Lon1 round
Hll4
• Plymouth
a1..., ..__
l,i,f,;,j HI~
Sea
1
0
Figure 1.30.3 A radial drainage p,,ttcrn
2
_ _ __,
2ml
4 km
Figure 1.30.4
/ '"~'fl
6•¥
Guadelwpe Passage
Deve 'opmcnt of rad,ai drainage patterns flowing
from Montserrat's voicanic centre towards the sea
Coral reefs
LEARNING OUTCOMES
W hat is a coral reef?
• Understand the irrportance
of coral reefs.
A coral reef is a hard rocky ridge buil1 up from the seabed by mill'ons
of tiny living coral organisms. It is their hard exoskeleto ns that form
the reef itself. Coral reefs are important for several reasons:
• Understand the cond itions
needed for coral reefs to
form.
• Understand the characteristics
and format on of cora reefs
in the Caribbean.
• Understand the irrportance
of coral reefs for coasta
protection, material for
beaches, ecology and
socio-econom•c benefits.
• They form o ne of the richest ecosystems on Ea rth, supporting ma ny
thousands o f species of fish, plants and other o rganisms.
• M illions of people v;orldwide depend o n fish caught from cora l
reefs, particularly m the developing world . In East Asia, over 1 billion
persons are supported by fish caugh t in neighbou ring coral reefs.
• W ith their stunning beauty coral reefs are popular attractions for
tourists in the Caribbea n, earning the region an estimated USS10
billion per year (see Figure 1.31 .1).
• Coral reefs form a physical barrier to tro pical storms and hu rncanes,
helping to protect the ma inland coast from povverfu l storm surges.
• Algae and sponges on coral reefs have valuable medicinal qualities
that scientists believe migh t be used in the future to treat viruses
and some cancers.
•• •
Coral reefs only account for
0. 18 per cent of t he marine
environment yet they are home
to nearly 25 per cent o f all
kno\'vn marine species. In the
Caribbean, coral reefs support
500-600 species of fish as well
as hundreds of other spec'es o f
pants and animals. One of the
most 1eonic animals associated
with the coral reefs in the
Caribbean is the endangered
sea turtle, which feeds main y
on seagrasses on the sheltered
landward side of the reefs.
Types of coral reef in the Caribbean
There are three main types o f coral reef.
1 Fri nging reef
Fringing reefs are shallow-water reefs that run roug hly parallel to the
coast. They form from the gradual accu mulatio n of coral over a long
period of time in ideal environmen tal conditions (see Figure 1.31 .2) .
A shallow lagoon is often formed betvveen the reef and the shore
and this is usually rich in marine life. Storms, such as hurricanes, can
occasio nally break up fringing reefs to leave behind isolated reefs
rather than a single continuous feature.
White sandy
beach
Shallow water
Broken reef fragments
channel
Fringing reef (from marine erosion)
Approx. 1 km
Figure 1.31 .2 Airing,ngreef
2 Barrier reef
Barrier reefs are much more extensive features than fringing reefs and
are found further out to sea. The most famous example is Australia's
Great Barrier Reef, which runs For some 2,600km off the east coast of
Queensla nd. The largest barrier reef in the Caribbean (second largest
m the \,vorld) lies some 25 km off the coas1 of Belize.
Look at Figure 1.31.3 \,vhich sho\'VS a ba rrier reef.
• A barrier reef probably begins life as a normal fringing reef.
• A gradual rise in sea level over a long period of time floods the coastline
creating a wide body of water between the shore and the reef.
• Wh ile the reef continues to grow it remains some distance away
from t he coast.
Gently sloping
coast
Deep water
Barrier reef
/
l
sea
\. level
'\ ·se
Figure 1.31 .3 A barrierreef
3 Atoll reef
A coral atoll is an isolated, almost circula r, ring-sha ped reef wi th a
deep lagoon in its centre. Coral atolls are largely concentrated in the
Paci fic and Indian Oceans, for example the Maldives.
Coral atolls often form at submarine seamounts (extinct volcanoes)
w here the rim of the crater creates the shallow water condit,ons
necessary for coral gro1,,vth (see rigure 1.31.4). The deep lagoon
forms in the extinct volcano's crater, or caldera.
Subsiding inactive volcano
Atoll Lagoon (was once abovesea level)
Sea
level
\
Coral formation
Look at f igure 1.31.5. It shows the distribution of coral reefs in the
Caribbean. Corals thrive in the Caribbean because conditions are ideal
for their g rovvth.
• Tempera tures - corals only live in seawater that has an average
tempera ture of 18°C or more. The ideal temperature is 23-5°C
• Salinity - the right amount of salt is needed. Corals thrive best in the
open sea away from the freshwate,- that is found at the mouths of rivers.
• Light - corals thrive in shallow 1,vater conditions because the alga e
on which they feed require light lo photosynthesise.
• Clear well-aerated water - polluted water, particularly if it con tains
lots of sediment, reduces light and can affect the coral's ability to
feed. Lack of oxygen can cause the corals to die. They grow fastest
1,vhere currents bring food .
• Turbidity - some water movement (turbidity) is necessary to provide
food and oxygenated 1,vater to the coral, but strong currents agitate
sediment and this reduces sunlig ht and smothers coral, preventing
feeding and respiration.
• Presence of beneficial algae and fish - coral enjoy a symbiotic
(harmless) rela tionship with algae (zooxanthellae) and fish. Algae
live 1,vithm the coral and provide it with energy (food). Fish shelter
in coral reefs and breed t here. Corals can consume small fish.
Okm500N
+
<)
Gulf of Me;r,co
,-
_ _!."':,,of._:\ Bahamas)/ll •
•
•
' \~ .
• •
~
..'·.• . .
•
•
r
Mexfco
1- 715 "
,'
'
~
Atlantic Ocean
;,~
.-
.,.e
"'
•
,,
? .,,.._
·aq,
ua
"
~
•,
,
"
,
~•
•
i:,uatema1.t Ho~duraJ_ - .,,,
1 •
"', ,
El Salvador
~lcaragu , •
""
C
'<I
··C
Jamarca ....,..,
""
"
~JG~
c::r.-".,
Puerto
Rico
l
HaldDomlcan "'
Caribbean sea
:•
.,_,. •
--1~
Pacific Ocean
[O
\
Colombia - - "
'
'
Dominica
Manlnlqu~
St Lucia
,..
.,
&renada Barbados
1
~
Fi ure 1.31,5 D,str'bution of coral reefs 'n the carbbean
"" 0.
,.~,
•
Republic
Venezuela
'-·---
The importance of coral reefs
Coral reefs are extremely important ecosystems providing a range
of benefits. An estimated 500 millio n people depend on coral reefs
for food, coastal protection, build ing materials and income from
tou rism. About 30 million people are totally dependent on coral reefs
for their livelihoods or because they live o n atolls.
The main benefi ts of corals include the following :
• Coastal protectio n - coral reefs act as buffer zones, providing
vital shoreline protection from storms and tsunami. The shallow
wa ter above a reef forces \'\laves to break early before reach 'ng
the mainla nd shore. This reduces coastal erosion and the risk o f
flooding. Corals also provide sheltered conditions for the growth
of mangrove forests, \,vhich themselves are important breeding
grounds for fish.
• Beach developmen t - t he erosio n of coral reefs creates the w hite
sand that typically forms the beaches of tropical coastlines. Some of
t his sa nd is extracted for the constructio n industry to make cement.
• Ecological benefits - coral reefs are extremely d iverse ecosystems.
One hectare o f reef off South East Asia was found to support over
2,000 species o f fish. Coral reefs are important breeding grou nds
fo r fish, offering shelter and food .
• Socio-economic benefits - the global value of the \<Vorld's coral
reefs has been estima ted at almost US$30 billion each year.
Coral reefs are extremely importan t commercial fishing grou nds,
providing some 25 per cent of the Less Economically Developed
Countries' (LEDCs) total fish catch. It is estimated that coral reef
fisheries in East Asia feed over 1 billion people. Coral reefs are
extremely popular tourist desfnations, providing a huge source
of income and employmen t for thousands of people. 1Vlillions of
people visit the Caribbean each yea r to enjoy its tropical beaches
and coral reefs. Coral reefs are also increasingly valued for
medicinal pu rposes. Scien tists believe that some coral species cou ld
be a fundamental sou rce o f life-saving or life-enhacing produc1s.
Coral reefs provide a home to
over 25 per cent of all known
marine species.
Mangrove wetlands
LEARNING OUTCOME
What are mangrove wetlands?
• Understand the irr portance
of mangrove wetlands for
coastal protection, ecology
and soc a-economic benefits.
Ma ngrove wetlands or swam ps are coastal ecosystems found in
tropical and subtropical regions (see Figure 1.32.1). Notice that
mangroves are fou nd extensively in the Caribbean as well as in
many other regions around t he world. One of the largest mangrove
swamps in the world is on Florida's south-west coast.
Ma ngrove swamps are characterised by halophytic (salt loving) trees,
shrubs and other plants growing in brackish to saline tidal waters.
These wetlands are often found in estuaries, where fresh \'Valer
meets salt wa ter. They are infamous for their dense maze of woody
vegetation.
,
C,
1
■
Mangrove wetland
Figure 1.32.1 Global distribLJ1ion of mangrove swamps
Caribbean mangrove wetland ecosystems
In the Caribbean there are three types of mangrove:
• Red mangroves - these are found closes t to the sea and have their
roots submerged at high tide. They cope with high levels of salt
by obtaining \'\la ter from the ocean th rough a process known as
' reverse osmosis'. The long arching aerial woody roots help anchor
the plant in the soft muddy sediment. It is through the roots
that oxyg en is obtained . The roots also trap sed iment, helping to
sta bilise this coastal environment.
• Black mang roves and \'Vhite mang roves - these are found further
inland where conditions are saltier. They do not have the extensive
aerial root systems of the red mangroves. They cope by excreting
t he excess salt onto their leaves. They can transfer oxygen direct to
the roots.
• •
In the tsunami of 2004, many
areas o f Indonesia Ihat were stil
protected by their mangroves
had relatively li ttle damage to
human structures.
Why are mangrove wetlands important?
Mangrove wetlands have several very important functio ns
(see Figu re 1. 32 .2):
• Coastal protection - the dense tangle of ma ng rove roots help
to trap sedi ment. This creates an effective coastal defence to
hurricanes, storm surges and tsunami. As sea levels rise due to
global ~varming, mangroves will con tinu e to grow and thrive,
provid ing lasting protect ion to coastal areas. If the mangroves are
removed, the muddy sediment quickly washes away leaving the
coastline unprotected.
• Ecological (biodiversity) importance - mangrove swamps
provide valuable hab itats for many species o f anima l and fish,
w hich benefit from the calm, sheltered waters. These ecosystems
sustain billions of worms, protozoa, barnacles and oysters, which
in turn feed fish and shrimp. These then support wading birds,
pelicans, and the endangered crocodile (see f igu re 1.32.3).
1/a,;rn-,e
SI\Jre.lne
p'Olectio1
Swioe
f1Q:n V.'it','1
(8SOJ'C
""""
b:1ldl11g
..
s,e·ar'cr
il!IU8~C l ''
Ash
t
Sllrhro
SoJroe tt'
focd lorma,13rQ\'f
!ood >t:e:,
1.1,rshcrao
Cro•,11n Sea
~ONJ'l
Figure 1.32 .2 The ,rnportar.ce of mangrove we:lar.ds
sql.irts
HenTI
8rttle
cru,
ilar
Figure 1.32.3 Crocodi e swmming in the Black River, Jamaica
• Socio -economic benefits - mangrove swamps are popular tourist
attractions despite the biting insects. Visitors can apprecia te the
vvide variety of flora and fauna in their natural habitat. Mangroves
provide many products and raw materials and they have significant
values for local communities (see Figure 1.32.4).
H
LD ITEMS
• umltllre
• glue
FOODANDDRINK
• honey
• oils
• fish
• vegetables
• fermented
d~nks
• VloX
RJEL
• firewood
• charcoal
• alcohol
SOCIO-ECONOMIC
IMPORTANCE
• matchstlcks
• p2pe1
• hair oil
TEXTILES
• dyes
• sldns.1ur
• synihellc fibres (e.9. rayon)
MEDICINES
- leaves
- from seeds, fruit and seeds
CONSTRUCTION
• t m er
• boat bulldlng
• thatch
CLIMATE
• oroductlon of oxygen
• eamon sink
SOCIAL VALUES
• eunural, splntual, religious
- heritage
• arllstlc
- recreation and tourism
• educalion
Figure 1.32.4 Socio•econom:c importance of mangrove wetlands
SUMMARY QUESTION
Construct a sumr>iary spider diagram to descr,be
why mangrqve wetlands are ·mportant natural
environments.
'
.
CASE STUDY
Black Rver Lower Morass, 1,imaica
The Black River Lower Morass (a lso known as the Great Morass) is Jamaica's largest wetland (5,700 ha)
and is a refuge for l\,vo endangered species, the American crocodile (see f igure 1.32.3) and the
West Ind ian ma natee. An internationally recognised \,vetland, 1t is protected by t he Jamaican Wildlife
Protection Act.
0
\\-
\
"-
Black River
f,
\\ Kingston "
'=-=C
.
Figure 1.32 .5 lhe Black River, Jamaica
The Black River Lower Morass is an important breeding ground for fish and home to over one hundred
species of bird, including ospreys, herons and flamingos. It is a vital economic resource supporting over
20,000 local people by providing opportunities for fishing and tourism. Abundant stands of thatch palm
are used by local people for basket making and as a roofing material.
Tourists are attracted to the mangrove wetland, seeing it as wild and mysterious (see f igure 1.32.6).
The prospect of viewing crocodiles and birds 1s a maior d ra>N for visitors. Tour opera tors encourage
exploration by kayak, sea bikes and hiking tra ils. Many local businesses as well as hotels and restaurants
have benefited from this example of adventure tourism. With the threat of peat mining (for energy) and
agricu lture, income generation from tourism has provided an economic benefit that helps to protect and
conserve the area from futu re development and potential damage.
Figure 1.32.6 To-!.lrists visiting the Black Ri\'er Lower Morass, Jamaica
Natural hazards and
natural disasters
LEARNING OUTCOMES
• Understand the terl"'ls
'natural hazard', 'risk' and
'vulnerability'.
• Understand that the
Caribbean ,s al r sk from a
range of natura hazards.
• Understand recent trends in
nalural hazards.
• Understand the short-terrr
and long-term responses to
hazards.
W hat are natural hazards?
A natural hazard can be defined as a natural ly occurring event, such
as an earthqua ke or a la ndslide, that poses a threat or risk to people.
The catastrophic consequences of such an event, particula rly in areas
of high population density, are what is called a natural disaster.
The lerm 'risk· is used lo describe the likelihood of a hazard
occurring . Those who choose to live close to a volcano are putting
themselves at high risk of being affected by a fu ture eruption.
Individuals living on the ban ks of a river are much more at risk from
flooding than those who live many miles away.
Vulnerability is a term used to identffy those individuals who are
likely to be more affected 1han others by a particula r even1. For
example, 1he elderly and the very young may be more vulnerable
because they can no1 move to safety as quickly as others.
Natural hazards in the Caribbean
Look at Figure 1.33.2. 11 sho,Ns some of the main natural hazards
that have affected the Ca ribbean in recent years. Notice that the
Caribbean is vulnerable to a range of hazards.
• Earthquakes and volcanoes . Several countries lie on or are close
Fi
Ha tians negoiiate a flooded
"-==== street in Haiti after Hurr'cane
Tomas battered the count,y
with heavy rams
to an active tectonic plate marg in and are at risk from earthqua kes
and volcanoes. Some recent eruptions and eart hquakes are shown
on Figure 1.33.2, includ ing the devasta ting Haiti earthquake of
2010, which killed some 230,000 persons.
• Hurricanes. The Caribbean is of1en struck by tropical storms and
hurricanes that have been formed in the North Atlantic and drift
\<Vest,Nards \<Vith the trade winds. In 2011, Hurrica ne Irene caused
flooding and damage in the Bahamas.
• Landsli des. Landslides are common in mountainous regions of the
Ca ribbean. Triggered by heavy rain fall or earthqua kes, they can bury
villages, block roads and destroy crops. (See 'Mass movemen t' on
pages 22-3.)
• Floods and storm surges. Tropical storms and hurricanes can dump
huge quantities of rainfall during the summer months, often leading
to flash floods. Flat coastal zones are a, risk from rapid rises in sea
level called storm surges which are associated with passing hurricanes.
(See 'Hurricanes' on pages 42- 5.)
Trends in natural hazards
In recent decades there has been an increase ·n the number of
individuals affected by hazards. There are several reasons for this trend:
• An increase in population resulting in individuals living in more
hazardous locations, such as d ose 1o the sea or on steep slopes.
• Deforestation
Haiti, Oomln?can Republic and Puer1o Rico
Jamaica
Bahamas
Halli
Ht.'<11ClU:$
Ea,mqu,ka (201QJ flae<ts (21))4) af.d <;arf<1s!!des lle:""Stto\'ed :hoi;sant1$' or
has increased the
l ropt al Sl(IIM mcole (20-10)
kJIJed an esnmjl!il r~mesand ~l"' o'lt' 2.000:-,,.,s~nf
b(l)1,1gff~ 'IOOCl '10: ancrlarl!!sldet , ,,.,e (2\)l 1r
likelihood of landslides
<1esi,05•1~g"IOJ$19S, rcat1s ana
cavsed
21.0.000 """~'$
ano1e11 q•'Jjt
~tl'$1\•a
and flash floods.
e,cns
Antigua and Barbuda
, rouloo oomMSs
daina:e
t-1~caresu1s ~nd r,.'arr,,n (1995)
• More families living
t;lfQllQr'lll•ilnd"$ Ol 170-~~~,
Cuba
in poverty lack
Httrtoa1·~ Geo,g~ (l998t a1a.HUri1ta11e
E;ir1'q,ake (19'!2) <led
8il!ln'l3$
Oma· (20Q,8) <:auseci ~ensi-v.9 oamage tr:,
40 P(ltSO'lt antt camag110
the resou rces 10
hnnes arii ~rtast:Jt'.L1'e
a ~el 800 bli!!Ct10$
respond effectively
tJ:ifliea'le w ma (200~1
brought .@Bnslve. I o~ClnQ
to the threa t of an
anc roi.d~i~ei
Monlurrat
even t such as an
J:tinliw
,..
VQ-:::anq. S()ijf(j81a HIil$ e!ll:'.ll~t
earthqua ke. They may,
_ _ 099!i-97J. K•Jlfg 19-lerSQ1S ar,d
~ L<SiOO~ m~se\•~c~alfon i9
for example, live in
r'l$arby C'llJn!ii't
Dominican Rept1blic
poorly constructed
H]Nca,e Go~Jl!" ('~ ~) bi'Qugl\lWlnds
houses that are
o1 170J(~t ano kH1ee 350 perso'ls
vulnerable to collapse
Mlirllnlque
during an earthquake
Ea1t1,,1,lj 12007) kHled 61lef!l)nj
and!njutoo ove« 400
or a hurricane.
• Changes to the
0
natural environmen1,
Figure 1.33.2 Natural hazards in the Caribbean
such as climatic cycles
(e.g. El Nino) and
global warming that
might be increasing the magnitude and frequency of storms.
l
.....
\
Responses to natural hazards
Short-term responses
Immediately after an event has occurred everyone is concerned with
providing emergency hep to those who have been affected. Search
and rescue is the immediate response. Locals will often dig \>Vith their
bare hands to search for those trapped or buned. Shortly afterwards
the main focus is on providing medical care, food , water and
emergency shelter. These responses, that take place in the first few
hours, are short- term responses.
Long-term responses
In the days and weeks after an event such as an earthquake or a
flood, attention shifts to consider rebuilding houses, shops and
offices. Communication systems such as roads may need rebuilding
and services damaged by the event (e.g. water, sanitation and
electricity) will need to be reconnected.
Government agencies may improve information for preparedness
and guidelines may be developed to improve the design of bu ildings,
which leads to improved building codes. Areas that are most
vulnerable to natural events may be mapped and actions taken to
restrict these areas for uses such as ag riculture, savannas and reserves.
Aid
Responding to a disaster requires a huge amount of money and
considerable expertise. Often foreign countries, trading blocs (such as
the European Union) and charities offer financial support or expertise
such as specialist search and rescue teams or helicopters. This support is
called aid and countries affected by natural disasters usually we!come it.
• • •
•
The Ha'ti earthquake ·n 2010
killed more than 200,000
persons, mak' ng it one of the
'top 40' natural disasters ever
recorded. In the Caribbean,
Jamaica has recorded the
greatest nurr ber of hazard
events, lnc.uding earthquakes,
hurricanes, floods and
landslides.
Volcanoes in the Caribbean
LEARNING OUTCOMES
Look at f igure 1.33.3. It shows the plate margins in the Caribbean and
the location of the major active volcanoes. No tice the following patterns:
• Describe the pattern of
volcanoes 1n the Caribbean.
• Understand the hazards
associated with Caribbean
volcanoes.
• There is a belt o f active volcanoes in the eastern Caribbean, stretching
from Mt St Catherine on Grenada to Soufriere Hills on Montserrat.
• Understand the irrpacts and
responses associated with
the erup tion of Soufriere H lls
volcano on Montserrat.
• The volcanoes lie on a destructive plate margin at the boundary of the
Caribbean plate and the South American pla te.
• The belt of volcanic islands form an island arc.
• The only o ther active volcanoes lie at the \,;estern edge of the
Caribbean plate in Central America .
Volcanic hazards in the Caribbean
The volcanoes in t he Caribbean are typical of volcanoes found at
destructive pla te margins. They are explosive and potentially extremely
destructive. In the past they have caused considerable devastation and
loss of Iife.
Known as the 'Emerald
Isle', Vlontserrat 1s a British
protectorate \,;hose primary
income came from tourism,
With the opening of a ne'N
a rport in 2005, tourism is
starting to recover, particularly
volcano tourism I
The following are the main hazards associated wi th volcanic eruptions in
the Caribbean :
• Pyroclastic flows: probably the most deadly hazard. They are
superheated clouds of ash and rocks that move at tremendous speeds
(up to 200 m/s) down the sides o f a volcano. Nothing can survive the
destructive force o f a pyroclastic flow.
• Ashfalls can be very
90'\V
extensive and can bury
settlemen ts, roads and
agricultural land. House
roo fs collapse under the
\,;eight of deposited ash.
,
• Lahars are mud/lows,
0 ~1l11]en'! l)'.oie IIOJ~l!ary'
(Jti:n mtwlnQ apat1)
......, Co11·1e101mt p!a!e 001.nd~•
-
N COCOS PLA E
t
O
<m
O
_
(,P,,r,~es co!!c!no}
Trans'orm 11!a1err~!11
fp .:~es s! dl11g ~asl e.a&11 O!her)
~ Ore~o" QI p,ze mo'i8meat
-
Ocean ire,ch
Vt1lc1nca•c
• lh;or a.."11\•a Y(}Ci.'ll)
A -Olher ad~·a ~~!carc;1
o 11.-~r sart~qua'.<!
~':-- - -..--- - - - - - - - - - - -~
Flgure 1 .33. 3 Tectonic hazards in the Qlrlbbean
often resulting from
snowmelt or heavy rainfall
\,;ashing ash down the
volcano's sides. Like
pyroclastic flo\,;s, lahars
can move at tremendous
speeds and can be
extremely destructive.
• Landslides can be
triggered by volcanic
eruptions, especially on the
steep sides of a volcano
\,;hen loose rocks (tephra)
have been deposited.
CASE STUDY
Soufriere -ii s, Montserra t (1995-97)
Event
• In July 1995, after a dormant period of some 350 years, Soufriere Hills volcano burst into life.
• Therevvere several small eruptions throughout 1995-96 leading to a major eruption in June 1997.
• The volcano has continued to show s·gns of activity to the present day. It last erupted in 2010.
• Eruptions have involved pyroclastic flows, ashfalls and lahars.
4,Q()O relfl~flUIQ fllia1:>.1an1s of
1hf11,000onglna po1>JlaLon
antcram«id ,.,~Q tilt ~ortnern
sa•e zor,•
Central bi.1'er ~o._,e evacua~ed
or 16 August 1991.
.-----~
1
Fo11>k1<14n10ne ·t.1h$re-S1>trfrl&.re H s
vQlcaoo and cap1a (PiYmouih) are
IQcated F·s1 ~eia tq.. be e·,acuau1d.
0
Figure 1.33.4 Impact of the eruption of Soufrere H·lls volcano, tv•omserrat
Impacts
• Ash and lahars buried much of the capital, Plymouth, and destroyed St Patrick's village.
• Vast areas of productive farmland were covered by ash and crops were des1royed.
• 19 people were killed in the 1997 eruption.
• Montserra t's thriving tourist industry 'Nas destroyed.
Responses
• After the first eruptions in 1995, people \'llere evacuated from settlements in southern 1'v1on tserrat,
including the capital Plymouth. Some people moved to safety in the north of the island , Others ,,._,ere
transported by ferry to Antigua. About two-thirds of the population was evacua ted.
• The UK government provided £41 million
in aid to support the local people who
had been evacuated.
• While much of southern Mon tserrat
remains a 'forbidden zone' some
foreigners have con tinued to visit their
holiday homes in the area, putting
themselves at risk from future eruptions.
• The volcano is monitored for further
activity. Scientists study patterns of
earthquakes, composition of gases and
changes in the physical shape of the
volcano.
LEARNING OUTCOMES
• Describe the patterns of
earthquakes in the Caribbean.
• Understand the hazards
associated with earthqJakes.
• Understand the irrpacts
and responses to the Hai ti
earthquake in 2010.
•
Scientists have recen tly
published a warning of a
poss'ble tsunami risk in t he
Caribbean. A 1 million tonne
b1ock of rock on the northern
flank of Morne aux Diables
vo•cano on Dom1mca is be ng
undercu I by coastal erosion.
,fit co lapses into the sea, it
could trigger a 3 m tsunami that
could devasta te the coast of
Guadeloupe and threaten the
Ives of 30,000 persons.
Earthquakes in the Caribbean
Look back to Figure 1.33.3 on page 98. Notice that earthquakes
occur in a zone running roughly parallel to the tectonic pla te
margins. They are a common occurrence in the Caribbean and
represent a signi ficant threat to individuals and property.
Look at Figure 1.33.6. It shows the location of large earthquakes
from 1610 lo 2004. Notice the following patterns:
• Earthquakes occur in a narrow band through the islands of the
Lesser Antilles and the Greater Antilles.
• Another narrow band of earthquakes stretches along the west
coast of Central America.
• Most of the earthquakes have a shallow focus, particularly along the
transform plate margin bel\-veen the Caribbean plate and t he North
American plate. These are particularly destructive earthquakes .
• Some deep-focus earthq uakes occur at the destructive plate margin
to the east.
• Some earthquakes trigger tsunami .
The earthquake hazard
Earthquakes are a serious threat to many people living in the
Caribbean. As recently as 2010 some 230,000 persons lost their lives
after a powerful earthquake struck Port-au-Prince on Hai ti .
The Richter scale measu res the magnitude of an earthquake. This is
a logarithmic scale t hat does not have an absolu te upper limit. Most
destructive earthquakes have a Richter scale value over 5.5. The Haiti
earthquake in 2010 measu red 7.0.
The effects of an earthquake are measured by the Modified Mercalli
scale.
The following are the main
70"!,/ 65"W 60"W
earthquake haza rds:
0 km 500
• Ground shaki ng - over 95 per
1oo·w
95'W
'
90"!,/
85'W
'
Figure 1 .33.6 Earthquakes in the Caribbean
I I
cent of deaths from earthquakes
occur when buildings collapse
follO\-ving ground shaking.
• Liquefaction - when silt
sediments are shaken they
become jelly-like, often causing
buildings to lean or collapse.
• Landslides - these are often
triggered by earthquakes and can
destroy buildings and cause loss
of life. They can hamper rescue
efforts by blocking roads.
• Tsunami - when earthqua kes occur in the ocean, displacement o f
the seabed can trigger 'Naves which, as t hey approach the shore,
rise to heigh ts o f 10 m o r more and flood the land.
CASE STUDY
H;i iti ea rt hq uali;e (2010}
Event
~
• Shortly before 5 p.m. on 12 January
20 10, a powerful 7.0 magnitude
earthquake struck Haiti, with its
epicentre just 25 km west o f the capital
Port-au-Prince.
• The earthquake resulted from a
sudden shift along a fault li ne running
parallel to the 1ransform plate margin
separati ng t he Caribbean plate and the
North American plate.
N
+_,_
Jeremie
• Violent g round shaking caused
tremendous destruction throughou t
Ha iti.
Impacts
9
• An esti mated 230,000 persons were
Figure 1.33.7 Location of the Ha ti earthquake 2010
killed and over a million made homeless;
many thousand were still living in
appall ing conditions in camps over a year af1er t he event.
• Approximately 250,000 homes were destroyed.
• Public build ings such as hospitals and schools were destroyed, and services such as water and
electricity were cut o ff. The airport and sea port were badly damaged, p reventing emergency supplies
from entering the country.
• Ninety per cen t of Port-au-Prince was damaged
• Diseases such as cholera became
widespread in the temporary camps over 4,000 died from cholera.
Responses
• Immediate responses focused o n search
and rescue and the provision of water,
food and shelter.
• Makeshif1 hospitals were set up and
medics operated o n people in the open
air, o f1en \'Vithout anaesthetic.
• The US military, United Nations, other
Caribbean countries and aid agencies
provided emergency supplies and
assisted in maintaining la\'V and order.
• In the mon ths that follovved, a massive
rebuild ing programme began .
by the earthquake.
LEARNING OUTCOMES
• Describe the patterns of
hurr'canes n the Caribbean.
• Understand the hazards
associated with hurricanes
• Understand the iwpacts and
responses to rlurricane Ivan
(2004).
The deadliest At anfc hurricane
occurred in 1780. Well over
25,000 persons were killed
as the hurricane tore into the
l esser Antilles. Winds of over
300kph devastated Barbados
and caused widespread damage
,n Martinique and St Lucia.
Hurricanes in the Caribbean
Hurricanes are the most violent and frequent hazards to strike the
Caribbean. During the hurricane season, vvhich runs from June to
November, powerful tropical storms track vvestwards from the warm
Atla ntic Ocean towards the Caribbea n. Some of these storms develop
into hurricanes, \'Vhich have the potential to cause \'Videspread
destruction and loss of life.
Look at f igure 1 .33.9. It shows the tracks of North Atlantic hurricanes
in 2004, a yea r when several powerful storms lashed the Caribbean.
Notice the following patterns:
• Most hurricanes are formed in the Atlantic Ocean, west of Africa.
However, some hurricanes form closer to the Caribbean and may
even form in the Caribbean Sea towards the end of the season.
• Hurricanes track from east to west across the Caribbean driven by
the trade winds.
• They tend to curve northwards in the direction of the USA and
across the north Atlantic Ocean towards Europe. This is because of
the effec1 of the Earth's rotation.
• Hurricanes tend to intensify as they move westwards over the \'\/a rm
sea. When they hit land. they begin to lose their intensity as they
are cut off from thei r energy source (evaporated \'\later).
Hurricane hazards
Hurricanes are huge storms up to 800 km across. They can achieve
wind speeds in excess of 250 kph and dump huge quan1i ties of rainfall,
\'Vhich can cause extensive flooding.
G)
Hurricane
Tropical storm
Tropical depression
Hurricane Ivan
"
t O~
T
The strength of a hurricane is
measured by the Saffir-Simpson
scale. The most powerful hurricane
is a ca tegory 5 storm, which has the
potential to cause ex1ensive damage
and loss of life. The following a re
the main hazards associated with
hurricanes:
1,000km
Atlantic
Ocean \
Pacific
Ocean
Flgure 1.33.9 Tracks of hurricaoes n the North Atlanuc, 2004
<D
• Very strong \'Vinds with sustained
speeds in excess of 125 kph
(hurricane force) and gusts of over
200 kph. These winds will strip
roofs, upturn mobile homes and
flatten trees and crops.
• Heavy rainfall, with the potential
to cause flooding and 1rigger
landslides.
• Storm surges are
often the grea test
killers. A storm surge
H~'"de...,__ _ _ _ _ _ _ __
is a temporary rise
Moan sa:1 le•l(ll > - - - - - - - - - - - - - 1
in sea level, often
by severa l metres,
rformal high tide
causing sea\,vater to
Fi ure 1.33,10 A s1orm surge cauied by a h.:rricane
surge inland. It results
from the in tense low
pressure associated wit h t he hurricane (IO\<V pressu re enables the
wa ter to expand upwards) combining with the extremely strong
winds driving the hurrica ne onshore. f igure 1.33. 10 describes the
impacts of a storm surge.
to1,•:me:~:=::::;::====~
CASE STUDY
Hu rr ca ne Ivan (2004)
Hurricane Ivan was one of a number of powerful
hurricanes to pass through the Caribbean during
2004. ts path (track) is sho\,vn in Figure 1.33.9.
Event
• Hurricane Ivan was 1he fourth major hurricane
of the active 2004 season, reaching category 5
on the Saffir-Simpson scale.
• It first struck Grenada on 7 September before
passing over Jamaica and Grand Cayman, and
clipping Cu ba. It made landfall in Alabama,
USA on 16 September.
• Winds reached speeds of 270kph at the
height of the storm as it passed close to Grand
Cayman on 11 September.
• The hurricane spawned several devastating
tornadoes.
Impacts
• Many people were evacua ted from coastal
regions as Hurricane Ivan approached,
including 500,000 persons in Jamaica.
• A total of 212 persons \<Vere killed by 1he
hurricane, 64 of whom were 1n t he Canbbean
(mainly Grenada and Jamaica).
• In Grenada, 85 per cent of the island was
totally devastated, \,vith property damaged,
services cut off and crops destroyed.
39 people were killed. Damage was estimated
at over USSBOO mill ion.
• In Jamaica, floods and storm surges killed
17 people and left 18,000 homeless.
• Grand Cayman also su ffered considerable
damage to property.
Responses
• Thousands were evacuated as t he hurricane
approached .
• Emergency support (food, water, med ical
aid and shelter) was provided to the ma ny
thousands \<Vho were affected by the
hurrica ne.
• Rebuilding homes and the infrastructure took
many mon ths.
• Economic growth slowed dramatically due to
damage to industry, farming and tourism .
LEARNING OUTCOMES
• Understand the short-terrr
and long-term responses to
natural hazards.
• Understand the work of
national and regiona
organisations n disaster
r,anagement.
Short-term and long-term responses
When an event such as an earthquake or a hurricane strikes a
community, the commu nity responds. Short-term responses occur
in the first few hours and days after an event. They usually involve
local communities helping themselves and each other. Longer-term
responses take place in the following weeks and mon ths.
Short-term
• In the first few hours, those who have survived will concentra te on
search and rescue. They \<Viii try to find other people who are alive
but who may be buried or trapped.
• Medical attention and t he supply of wa ter, food and shelter are all
short-term considerations.
• Emergency help will probably arrive from both national and
international sources.
Long-term
lmmed ate respons,es
' -- = - - - --' fol owing the 20 10
earthquake n Ha "ti
" CASE STUDY
• Long-term response involves reconstruction, such as repairing
houses or building new ones. In most cases they will be built using
strict bu 'lding codes to enable them to better \<Vithstand a similar
event m the future.
• Infrastructure, such as roads and railways, may need repairing .
• Services, such as wa ter, electricity and sanitation, may need to be
restored.
• Businesses that have been destroyed may need financial help
to ena ble them to start up again. This is important to provide
employment for people.
JaP1a1ca's Office of D1sas1er Preparedness a.nd Emergency Management
Jamaica has been severely affected by natural
hazards, particularly flooding associated with
hurricanes. Established in 1973, this permanent
disaster management organisation is committed
to preventing or reducing the impacts of natural
hazards in Jamaica.
Its professionally trained staff work with
local communities and other national and
111ternational organisations to reduce people's
vulnerability to natural hazards. Achievements so
far include:
• Establishment of a Na tional Emergency
Operations Cen tre to take control when the
country is affected by an event.
''
• Development of disaster management plans and
establishment of parish disaster committees to
coordinate activities at the local level.
• Relocation of persons at high risk from natural
hazards to disaster shelters in each communi ty.
• Coordination of post-disaster assessment and
clean-up activities.
• Establishment of community flood-warning
systems.
• Deve!opment of websites and printed ma terial to
provide informa tion to people so that they can
be better prepared.
• Plans to reduce the ,mpac1 of future events will be made. This
may include improving building standards or increasing people's
awareness through education.
National responses
Natural hazards are common m the Caribbean, and all countries are
aware of the need to make prepara tions to minimise the impacts. An
Office of Disaster Prepared ness and Emergency Management
has been established in Jamaica, Antigua and Barbuda, Barbados, and
Trinidad and Tobago to oversee disaster management .
A ·:an is trapped by
...._.,,__ _ __, a bridge af1erf,oods
Regional responses
swept n off a road ,n
Grenada
In 1981, following severe floods and hurricane damage, the Pan
Caribbean Disaster Prevention and Preparation Project was established.
In 1991, this became the Cari bbean Disaster Emergency
Response Agency (CDERA). There are currently 16 participating
states within 1he Caribbean. CDERA's motto is '1\/lanaging Disasters
w ith Preparedness'. The insti1ution was reorganised in 2009 and was
given a new name. It is nov.i called CDE1\/1A, the Caribbean Disaster
Emergency Management Agency.
Disaster
impact
/
~
Response
Preparedness
EFectlveness depends on
training arid experience of
emergency response tea'Tls
Action to lncre;,se capacity
of a corrvnunity for prompt
and efficiem response
[ POST-DISASTER
I
I
Mitigation
'
Action to prevent property
damage and r,inlmise
economic impacts
\
Recovery
I PRE-DISASTER
I
Prevention
Action 10 mitigate 1he
severity o' impact
""'
Redevelopment
Action ,o redistrib~:e econo"1ic
osses (t~ere s~ou d oe a lorgter11 ~k t:e:ween c:saster-related
act vit es and nat onal aalvl:les)
Figure 1.33 .14 The d,saster management cycle
Action to assist
communities/nation 10
return ,o pre-disaster level
of function,ng
LEARNING OUTCOME
• Understand that the impacts
of hazards can be reduced
by phys ca and behav oural
approaches.
The following are CDEMA'.s main functions:
• Ma ke an immediate and coordina ted response to any disastrous
event in the participating states. This includes man-made
disasters such as oil spills and aircraft acc·dents as ,,veil as
natu ral haza rds.
• Reduce vulnerability of individuals to natural disasters by providing
information and guidance.
• Collate accu rate information about disasters in the region.
• Provide trai ning for disaster managemen t personnel.
• Mainta in a dynamic website to provide up-to-date informa tion, for
example weather forecasts.
CDEMA responds to events that are beyond the capacity of the
affected country or countries. Hurricane Ivan (see the case study,
page 103) in 2004 is an example of an event \'Vhich caused such
widespread devastation that those individual countries (particularly
Grenada) simply could not cope.
Managing natural hazards: floods, landslides,
volcanoes and earthquakes
Jamaica is prone to a range
of natural hazards, including
hurricanes, earthquakes and
landslides. In 1988, Hurricane
Gilbert destroyed 60 per cent of
the is and's water suppFes and
triggered 478 landslides - 45
persons were killed .
It is possible to identify two distinct approaches to ma naging natural
hazards:
1 Physical approaches - these involve attempts to prevent hazards
occurring or building structures to prevent or reduce their impacts.
2 Behavioural approaches - these involve adapting people's
behaviour so that they become less vulnerable. Examples include
\'Varnmgs and forecasts, evacuation, education and awareness,
land-use zoning, hazard mapping and insurance.
Physical approaches in reducing the flood hazard
Flooding, a common hazard in the Caribbean, is usually caused
by torrential rain fall associated \'Vith tropical storms or hurricanes.
A number of physical techniques have been used to contain
flood,,vaters and reduce their impacts on people and property.
• Check dams - these are small dams, usually formed of rock or
timber, that are built across small cha nnels and gullies to slow
down the flo,,v of \'Valer.
• Gab ions - w re cages filled w t h rocks can help to support and
strengthen river banks (see Figure 1.33. 15).
• Levees - raised river embankments that can increase the capacity
of a river cha nnel, makmg flooding of adjacent land less likely.
'.
• Paved drains - wide and deep paved drains are common
s:ghts alongside roads in towns (see Figure 1.33.16). While
these may be dry for most of the year, they are capable of
containi ng large volumes of water during heavy rainstorms.
Managing landscapes to prevent landslides
Most landslides are triggered by seismic activity or heavy
rainfall. However, human activi ties such as deforestation and
construction often make slopes more vulnerable to collapse.
Landscapes can be managed to reduce the risk of landslides
by:
Figure 1.33. 16
• planting trees
• stabilising slopes using pins or steel bolts
• improving drainage
• re-profiling a slope to reduce its angle.
Paved drai" in St Johns, Amigua
'Build back better': earthquake-proof buildings in Haiti
Much of the loss of life caused by the Haiti earthquake of 2010
resulted from the collapse of poorly built houses. Many of the schools
and homes had brittle walls and unreinforced masonry that simply
fell apart when ground shaking occurred.
• • •
At 1, 156m h·gh, the volcano
Mount l.>amuiga on St Kitts is
one of the highest peaks 1n the
Caribbean. t is c othed with
rainforest and has a 1 km crater,
v,hich contains a cra ter lake.
As the Haitian capital Port-au-Prince is rebuilt, there is a desire to
'build back better'. This means constructing ne1N buildings that are
built to withsta nd ground shaking. While no building can be 100 per
cent earthquake proof, it is possible to build more rigid constructions
that are less likely to collapse.
CASE STUDY
•
Volcano hazard risk r,app ng: St Kitts
In 2001, scientists from the University
of the West Indies published a volcanic
haza rd assessment map for St Kitts
to identify those areas most at risk
from future eruptions of Mt Liamuiga.
While the volcano has not erupted
since 1843, there have been periods of
earthquake swarms in 1974, 1988 and
2000, Indicating that the volcano is
still active and likely to erupt at some
point in t he futu re.
Figure 1.33.17 shows the different
haza rd zones on St Kitts. Notice that
the highest hazard zone is in the north
of the island . Even the yellow zone to
the south is at risk from ash falls.
Mt Liamuiga, in common with other
active volcanoes in the Caribbean,
is constantly monitored for signs of
activity.
Dieppe Bay Town
St Palf;t ..... - - , S~ lers
·
•·llf
le Vue
Ne•,~qii ~roun~m 'labernacla "tanslon
Fl Trea
Flat ..JI'.. llamulga · ~lcola Town
g p 1" :• Sa.'ldy· .Polil!"' Varchlld's Mt ..._
Sanymnt
d
_
•
\
1
Town
• ~nms11>ne HMI
Ca,on-----..
ST KI TTS \
.s'oti,,; fts: Cltfl~1')
'-■
Zone 1 Atea of hlgoos, hazard
~
~
~
Basseterre
Zone 2 TM area ls l!ke ~• to receive
heavy ash and pum<e fit
Zone 3 Tlt.s area Is l!ke)• 10 ,ece!ve
frequent a.1d s!gn!r cant asll fall
• Pe<1k/Summh
0 Eruplon 1/enl
Rl,;-er
L• \~Ponll
• san1emen1
Figure 1.33.17
Volcanic hazard zones In St Kitts
-~ ~ ",,.
Salt Pond
{: Peninsula
'
LEARNING OUTCOMES
• Understand the different
approaches to reducing the
hurr cane hazard.
• Understand how forecast ng
of Hurricane van's track
enabled scientists to issue
accurate warn ngs.
Earthquake-resistant fea tures include using reinforced concrete
(concrete \<Vith steel rods to give added support), supporting walls
and roofs wi th diagonal cross beams, and bolting buildings to their
founda tions.
Hazard mapping
Hazard maps can be used to provide info rma tion that can in fluence
people's behaviour and reduce their vulnerability to natural hazards
such as floodmg, la ndslides and volcan ic eruptions.
Based o n historic even ts and scientific su rveys, zones of different
levels of risk can be identified . Governmen ts may decide to restrict
developmen ts in high-risk zones or devise detailed evacuation plans.
By identifying the areas at greatest risk, actions can be taken to
reduce the likely impacts of an event.
For example, on Montserrat, the sou thern half of the island is an
exclusion zone, \,vhere no admittance is permitted apart from for
scienti fic monitoring.
How can the hurricane hazard be reduced?
Tropical storms and hurricanes are common in the Caribbean and are
capable o f causing considerable devastation. Look back to page 103 to
see how Hurricane Ivan caused extensive damage to Grenada in 2004.
Hurricanes are enormously powerful storms that cannot be controlled
o r prevented. This means that people have to find ways o f reducing
the impact o f the stro ng \<Vinds, heavy rainfall and storm surges.
These are some examples:
• Land-use zoning - hurricane damage tends to be focused o n low•
lying coastal areas and alongside rivers where flooding is a major
hazard. National governmen ts
can devise la nd-use plans to
keep vulnerable groups and
expensive land uses away from
these areas.
• Building regulations - new
buildings can be constructed
with strong \<Valls, doors,
windows and roofs to withstand
strong winds.
• Commu nications - telephone
and elec1ricity lines can be kept
well away from coastal areas o r
installed u nderground .
':
• Levees and embankments - these can be constructed to reduce the
flood risk and sea walls can be bu ilt to protect against storm surges
(see Figure 1.33.18).
• Trees- plan ted along coastal areas, trees (e.g. mangroves) help to
break up the power of \<Vaves and reduce the impact of a storm
surge.
• Hu rricane tracking, prediction and evacua tion - this is often the
most effective approach.
• •
Have you heard of hurricane
holes? They are safe coves and
estuaries on Caribbean is!ands
that offer some protection from
hurr canes.
Tracking hurricanes
Hurricanes are very distinctive
features and t hey can easily be
tracked by satelli tes as they move
across the ocean towards land.
Computer models based on past
hu rricane tracks help scientists
to predict the likely course of a
hu rricane. This enables warnings
to be issued, giving people time
to respond before the hurricane
arrives. Most hurricanes affecting
the Caribbean are tracked by the
National Hurricane Center in Miami,
USA.
Issuing warnings
\/\/hen a hurricane seems likely
to strike a country two levels of
warning a re issued:
1 Hurricane watch - this is
issued \<Vhen there 1s a threat of a
hurricane \<Vithin 24-36 hours.
2 Hurricane warning - this is
a higher level of warning and
is more of a probabili ty than
a possibility. It is issued when
hurricane condi tions are expected
in 24 hours or less.
Once a warning has been issued,
everyone starts to take precautions
by board ing up windows, turning
off gas, water and electricity supplies
and seeking shelter, possibly in a
designated hu rricane shelter. Advice
is available in printed booklets,
posters, on the rad io and television,
and on the internet.
CASE STUDY
Trackrng Hurr_.cane Ivan (2004)
Look at Figure 1.33.19. It sho\<VS the predicted track of Hurricane
Ivan at 1 1a.m. on Thursday, 9 September 2004. It has just
passed over Grenada, causing widespread devasta tion and killing
39 persons. Notice the following:
• A predicted track for the centre of the hurricane has been
drawn through to 8a.m. on Sunday, 12 September.
• The predicted track lakes the form of a cone, allowing for
an increasingly wide margin of error further into the forecast
period.
• Based on the predicted track, warnings have been issued, for
example Ja maica has a 'Hurricane Warning '.
The predicted t,ack will be constantly upda ted and refined,
allowing for greater precision in the issuing of warni ngs.
According to Figure 1.33. 19, Jamaica is directly in the firing line,
to be followed by Cuba. l ook back to Figure 1.33.9, page 102,
to see whether these cou ntries were hit by Hurricane Ivan.
Hurricane Ivan
9 September 2004
11 AM EDT Thursday
® Cum1n1 cen:re location
0 Forecast certrefos!t::011s
NWS TPS:Na:ior.al Hu1ricane C.ntre
l1lax
Wino 25 7J<p~
CulTI!'l1Mo,•em11n1 Wti.W at 24 k~h
Bahamas -
s,s,.,,.,,
(H-SI.S!&ltfdv.•11 > 117~)
H1111ta11e •11am!ng
1-tld'l'l<:Me watcn
- Trop:cal slorm♦,,arn!no
. - Trop.:cal siorm•11atcf!
Cuba
08AM Sun
Dominican
Hatti Rep.
Mexico
Belize
Jamaica
Honduras
Potential day 1-3
track area
~lcaragua
Figure t .33,19
08 AM Fri
• 1f AMThu
Predicted track o' Hurr,cane Ivan (1 i a.m. Thursday, 9 September)
I •
SECTION 1: Practice exam questions
···· · · ···~·····•00••00•1••· ·
,
E ua br
I
Ell'
Figure 1
' -= - - - - --'
World ootllne map
On the map provided (Figure 1),
insert and name two ranges of fold
moun tains, and give the map an
appropriate title.
b Describe, in one or two sentences,
each of the fo lowi ng:
i a dyke
ii a sill.
1 a
c
(5)
E........_
(4)
(4)
\B
Account for the forma tion of volcanoes
near subduction zones.
(12)
Draw a diagram to shov,, two effects
of soil creep.
(5)
b Define the fo'lowing processes:
weathering
(4)
ii erosion.
(4)
c Describe and account for the occurrence
of:
landslides
(6)
ii soil creep.
(6)
Sea;---1..._______
2 a
Figure 2 shows a river basin. Iden tify
the features abel ed A, B, C, D and E.
b Describe the four processes of erosion
by a nver.
3 a
I
(5)
(Bi
~ Fi.:!'
gu::.r.:..
e .:..
2_
c
..J
j
A (ver basin
Account for the formation of waterfalls
and the gorge downstream of a waterfall.
(12)
Figure 3 Is a diagram of the water cyc', e.
Identify the five processes labelled
A, B, C, D and E.
(5)
b Descr'be, in about four sentences,
(8)
how oxbov; lakes are formed.
4 a
c
d
6 a
Account for, and compare, trellis and
radial dra nage patterns.
(6)
Account for the development of deltas. (6)
Dravv and labe two d,agrams to show
the d,fference ber.,veen a barrier reef
and a fringing reef.
(5)
b State four conditions needed for coral
Sun
B
.....,_:...,.._;,
c
~
d
' ' '
,' ' ''' '''
', ,, ' ' A
' ' ,
,,,,,,
, .. _ ____.,.---;::;--I
7 a
C
Land
River
D
Land
b
!le
Ground water
...__
Fig::..u:..:.rec:....::..
3 _ _, The water cycle
b
c
d
(8)
Accou nt for the formation of caves
1n limestone areas.
(6)
Accou nt for the formation of spits.
(6)
Dravv four isobars to show the centre
o f a h urricane. Ind cate the pressure
and wind direction.
(4)
Define the following terms:
ii
iii
Percolation
5 a
reef formation.
Draw a diagram o f a limestone area to
sho1N four features (two on the surface
(4)
and two 1,mdergrou nd).
Define the terms 'carbonation' and
'mass \<Vasting'.
(4)
Descrlbe two processes of physical
\<Veathering.
(4)
Account for the development of four
(surface and/or underground) land forms
in limestone a1eas in t he Car.bbean,
other than those you named in a.
(12)
1v
(2)
(2)
weather
co.d front
tropical wave
ITCZ .
(2)
(2)
c
Explain fu lly how relief nfluences the
weath er and climate in t he Caribbean. (12)
8 a
On the world map p rovided (F gure 4),
Inser t and name two areas of t ropical
rainforests.
(5)
b
c
Describe the characterist•cs of the
vegetation of a tropical rainforest.
Ho\<V are the soils of the tropical
rainforest biome affected by the
climate and the vegeta tion?
I
I
.T! QPIC'. Qt 9/~p~r,.
.. -..... -~- --...
~ ~c.,· . . '
w '
Equatbr
I
w'
•... ~ ................. L.••. l.
Tropic of Capricorn
~
\
I
I
~
Flgure
4
\'llorl(l oatllne map
~--J
0
(8)
(12)
Global population
distribution and density
Global population distribut ion
LEARNING OUTCOMES
Population distribution describes the loca tion of individuals in
an area. Look at Figure 2.1.1. It is a dot map showing population
distribution in the world. No tice that each dot represents 100,000
persons. Imagine how the map 'Nould look if every person in the
world was shown by a single dot.
• Understand the global
patterns of population
distr bution and dens•ty.
• Understand the factors
affecting populat on
distr bution and dens ty.
Notice the follovving patterns:
• Population is not distributed evenly across the world.
• Some areas have high concentrations of population, such as
\>Vestern Europe, Ind ia, eastern China, sou th-east Africa and
southern Japa n.
• Some reg ions have few people, such as central, eastern and
northern Russia; much of Canada and Australia; northern Africa
(away from the coast).
• Many coastal reg ions have high population concentrations.
Advantages and problems of using dot maps
Dot ma ps show densely and sparsely populated areas dearly, both
between countries and within a country. In China t he great majori ty
fl.• 1-· ·; ' •
·;fh-'• "»
..
--,
a es
'
~x-- Amazon
Valley
Java
1 dot represents 100,000 persons
Figure 2.1 . 1
-
\'Vorld popu ation d1Str bution
•
of people live in the eastern half of the country, avoiding the difficult
desert and mountainous regions in the west. Choos•ng the ideal
value for dots is difficult. If a dot represents fewer people there are
too many dots and they merge, vvhich can confuse the person using
the map. However, if a dot represents a high number of people it
becomes i mposs1ble to show ho\<V people are spread across a sparsely
populated area such as western China.
Global population density
Popu lation density is defined as the number of people per km 2,
the relationship between people and the space t hey occupy. Cities
have higher population densities than rural areas because people
are concentrated into a smaller area. Here are some examples to
illustra te this:
• Manila (Philippines) has 46,000 people/km' (see Figu re 2.1 .3).
• Kibera (a slum district o f Nairobi, Kenya) is thought to have
90,000 people/km' .
• Kingston (Jamaica) has 1,358 people/km' - rather lower populatio n
density.
Compare t his da ta with rural St Andrew Parish (Barbados), w hich has
< 300 people/km'.
EXAM TIP
~o~ fo.,- t'1ese -featuyes o""
Flflu.,-e :2.:t.:t: t'1e I.ti bets o"'
the l¾t!p will give l:JOu clues.
• RiveYs attYact people _
th e c;a"'fjes, Nilt /;1111,of
Al¾/;IZOI,\, valltl:JS St/;1111,of
out iis Li"'!s of Yeol olots.
• tsta,,,,ols co.,,,ce,,,,triite
populiiti.ovcs - As snow""
foY ~ii""'-plt, L""..)Ava a"';
_}/;I !¾(;I icA.
• c;tobAl cities stA111,ol out As
co"'-Ce"'-triitiovcs cf olots
for ~i¾ple NM yorl<?,.'
iole~i.-tl:J otlier olevcselt,
/;IV\,{;( sparsetl:J populiiteol
Areas Across tne wortol .
Figure 2. 1.2 is a choropleth map showing global population density.
This is ho\<V a choropleth map works:
• A colour scale is devised to represent the range of population
density data.
• The colours are related to each other in the colour wheel - yellow/
orange/red/brown is usually used for popu lation density.
• The darker the colour, the higher the value it represents.
b
.
t -------__.:'.~~·f. .""'~;. ::-----§:!~:If=p
-
-
2
Over 500 persons perkm - ~;QJ~ --_:~~ ;t:4 C:C.:_---~~ r;,..=- Equator
200-500 persons per km2
)
,
100-199 persons per km211__---l~ ;--:c-'....__ _
Tropic of Capricorn
50-99 persons per km2
\ •
10--49 persons per km2
Under 10 persons per km 2
-B~ )~-~-----,~~~ ~
Fig u,., 2. 1.2
World population dens,ty
',
Notice the following patterns on Figure 2.1 .2:
• the areas of very high population density are
north-west Eu rope (especially the UK and
Germany); southern Asia (India, Pakistan and
Bang ladesh); China and Japan; Indonesia
• the areas of lo\,vest population dens,ty include
large parts of t he southern hemisphere (South
America, southern Africa and Australia) as \,veil as
sections of northern Africa and the Middle East.
Canada and Russia sta nd out in the northern
hemisphere.
Advantages and problems of using
choropleth maps
Choropleth maps are relatively easy to dra\,v and are better for
making compa risons bet\,veen countries than dot maps. Hovvever,
the single shading in choropleths suggests popu lation is evenly
spread across the cou ntry, which 1,ve have already seen 1s not true
in China . The USA and Austral ia also have low overall densities, but
their people are spread very unevenly. Figure 2 .1, 1 indicates a high
concentra tion of people along t he eastern seaboard of Austra lia
and large almost empty areas elsewhere.
Factors affecting population
distribution and density
There are several factors that affect 1,vhere individuals
live and therefore infl uence patterns of population
distribution and density.
1 Physical geography - Some environments
experience hostile living conditions, such as
deserts, high mountains and dense forests . These
areas tend to have fewer people than areas 1,vith
natural advantages such as fertile flat la nd and
well-watered river val leys. In China, for example,
fe,N people live in the H·malayan mountains
1,vhere the climate is extremely cold, the soils are
thin and infertile and the slopes are too steep
for farming. In contrast, the flat fertile valley
of the Yangtze River, with its good irrigation
opportunities and alluvial soils, is heavily
populated (see Figu re 2.1.4 opposite).
2 Climate - Some places experience clima tic
Figure 2.1.4
The Yangtze Riverin Shanghai
extremes, such as polar regions (e.g. nort hern
Canada and Siberia) and deserts (e.g. Saha ra
Desert in Africa). Few individuals choose to live
in these areas where it is ha rd to make a living (see Figure 2.1 .5).
Elsewhere, clima tic conditions m temperate and tropical regio ns
are less hostile to human settlement and these regions tend to
have higher population concentrations.
3 Proximity to the coast -An estimated two-thirds o f the
world's population live within 500 km of the coast and many live
on the coast itself. The main reasons for this are trade vvith other
cou ntries, the development of fishing and, more recen tly, the
development of tourism.
4 Resources - The presence of resources, particularly energy
resources such as coal, has had an important influence,
particularly in Europe and in parts of the USA. In Europe,
the Industrial Revolution vvas based on the extensive coal
resources in the UK, France and Germany. This explains the high
concentration of persons in t his region.
5 Rivers - Some maj or rivers are responsible for high
concentrations of persons. The River Nile in Egypt acts as an
important transport route and provides much-needed \'\la ter
for irrigation in an otherwise extremely arid country (see
Figures 2.1 .6 and 2.1 .7).
Figure 2. 1.6
The R··,er Nile
Figure 2.1 .5
A Bedouin camp in the
Sahara Desert
According to the World Atlas,
Monaco has the highest
population density ;n the world
at 16,500 people/km'. Singapore
Is second w ith 7,197 people/km' .
The Caribbean country with the
highest dens' ty is Barbados w 'th
596 people/km'. Austral'a is
190th n the \,vorld with a density
of just 3 peop,e/km 2• (wvvw.
\'Vorldatlas.corn, stats 2012-14).
Population distribution
and density in the
Caribbean
Population patterns in the Caribb ean - reasons for
high and low population densities
LEARNING OUTCOMES
• Describe popJ ation pa11erns
in the Caribbean
Look at f igure 2.2. 1, \'Vhich shows popu lation density in the region.
Caribbean islands have hig her densities than countries o n the
surrounding mainland o f North and South America. Globally, islands
att ract people. In the Caribbean this is true of several islands, but
particu larly true of Haiti and Martinique.
• Explain variations in populat on
d iskbJtion and density ·n the
Car bbean.
• Understand popu ation
density In Jamaica.
Haiti and Barbados, for example, have the highest population
densities, \'Vith > 1,000 people/km'. Caribbean islands favour
settlement because the climate encourages agricul1ure and tourism .
Ports such as Bridgetown and Port-au-Prince are important trade
hubs for the export of produce, including sugar.
The Dominican Repu blic has relatively low population density:
mountainous relief discourages settlemen t and most settlements
have coastal locations.
Guyana has the lowest
populat.on density in the
Caribbean, w th i ust 3. 5 persons
per square kilometre. This
coll" pares to the population
density of Jamaica w hich
is 249 persons per square
kilometre.
Key factors in population d istribution and density in Jamaica
• Relief and height of the land, rock type and drainage are key factors:
- The steeper the slo pe, the more d ifficult it is to build on - the
Blue Mountains m Jamaica repel larger settlements.
.,_
- Steep slopes also lead to thin soils, too poor to farm effectively.
•
G
•
(Ill)
,....,
I
A/o I A1lant1C:
o,c..,,,,,
lHEMmMI
<I
1-25
'6-100
IMI P Clll
Cll'W&W
l'lllll'IO - . : : -
(UI)
-
(111)
Slft.lUM
IUII
-·
PJ UUA_,
-
101-1$0
251-1,llOO
-
>1.000
i'PN
-·
· I PEP Pl,.,
II 1
C4
n- ••-- • '"-•
••
1101111
co: nr:■2
Figure 2.2.1
Populat·on densrty map of the Caribbean
__,
0
....
--'
- Rock types such as limestone create entirely u nique landscapes, generally
of little value for agriculture due to lack of surface wa ter, w hile at1ract,ng
limited numbers of tourists to see the u nique landscape, for example
Cockpit Country, Jamaica.
- Coastal plains provide flat land for building homes and businesses, as well
as for constructing transport routes. Of the g lobal population, 56 per cent
o f people live less than 200 m above sea level.
• Rivers flov,ing tov,ards the sea cross coastal plains, providing •Na ter-supply
and other port opportunities such as fishing and trade. These two factors,
plus the development of tourism, explain the o riginal loca tion and recent
expansio n of Kingston in Jamaica.
• Socio-economic factors are important - economic factors are to do vvit h
money and j obs; social factors involve health, education and other public
services. For example, many Caribbean settlements have grown recen tly
because of the pull factors of available jobs, especially in tourism. Jobs may
be seasonal (\,vhich 1s a d isadvantage), bu t people take what is o n otter. The
la rger the settlement the more services, for example retailing and banking,
are required for the population .
Opportunities in rural areas remain limit ed, leading to con tinuing rural to
urban migration in the Caribbean.
CASE STUDY
Populat on density in Jamaica
Look at Figure 2.2.2. It sho•NS populatio n density in Jamaica. Notice that the popula tion density for most
of the country is greater than 100 persons per square kilometre. While much of the coun try has a similar
population density, there are some notable variatio ns, which are largely the result of physical factors.
• Kingston - The population density here is over 1,000 persons per square kilometre. Kingston is the capital
of Jamaica and, w ith its thriving port, shops and industries, it attracts a lo t of people to live in the area.
• Blue Mountains - Here the population density is less than 100 persons per square kilometre. High
altitudes (Blue Mountain Peak rises to 2,256 m) and steep slopes crea te problems for farming and
communica tions. Few people choose to live here.
• Cockpi t Country - This is an extensive area of limestone. It also has a very lo\'\/ populatio n densi ty
(less t han 100 persons per square kilometre). The landscape is rocky, very undu lating and severe'y
weathered . There are few resources and limited opportu nities for farming.
ag-100
tOHIO
-
fft• l.000
.. --~
-• c..,••.GOO
--
Figure 2.2.2
bb n Saa
Population density map oi Jamaica
0
Population change
Population change key terms
LEARNING OUTCOMES
There are a few important geographical terms that you need to know
w hen studying population growth:
• Understand key population
change terms.
• Birth rate (SR) - number of babies born alive per 1,000 persons
per year.
• Understand the demographic
trans,tion model as a
background to understand ng
population change ·n the
Caribbean .
J-curve
• Death rate (DR) - number of individuals dy'ng per 1,000 persons
per year.
S-<:urve
• Natural change (NC)- the d ifference bet\,veen the birth
rate and the death ra te, but expressed as a percen tage
(per 100 persons) rather than per 1,000 persons.
Ze10
g10111h
• Natural increase (NI)- this is \,vhere there 1s a positive
natu ral change, that is, the birth rate is h igher than the
deat h rate.
C
.g
g_
El<J)onentlal
growth
~
E)(oonenttal
growth
Time
Figure 2.3.1
• Natural decrease (ND) - this is \'Vhere there is a
negative cha nge, that is, the b irth rate is lower than
the death ra te.
• Infant mortality - this is the number of
deaths in the age g rou p 1-12 mon ths per
1,000 live bir ths per year.
Time
TheJ -cur..e and the S-cuo,e
• Ch ild mortal ity - this takes account o f all
deaths of child ren up to the age of 5, per
1,000 children in that age g roup.
EXAM TIP
caribbea ... TotaL
11.R/ l>R/
Net
COi< "'-t"!:j
popi.d.at,ov. 1.,000/ 1.., 000/
"'-'0Yatio...,;
(l¾cLLL<>v.) IAt&l r
!,IOa Y 1.,,000 bt.m,,Le
f-tai.ti.
J&11,,\<.aLc.ei
niv.,,:ia,:(
l'l.<t96
~
.g
)"_J
-4.1.2
2.J30
1.ll'.4
6 .)'-
- 4.l,'3
1 .223
13.ll'
fl.S
- 6 .42
""""' TI>baoo
~
11.arbadcs
.st:
LM.ci.a
0 .2!,'<j
12.0
fl,4
-0.30
0 .163
1.3.q
r-3
-3.1..3
. ~- ...
l>ata SOI<
---------
. ~!
..
..
Births
Natural change
Population
change
Deaths
Figure 2.3.2
-----.......___....
Immigration
I Populafon change
Migration
Emigration
• Life expectancy - this is the number of
yea rs that individuals are expected to live
from birth in a particular country.
• Migration - this is the movement o f
individuals from place to place - changing
residence wi th the intention of remaining
in the new place for at least o ne year.
• Immigration - this is movemen t into
another coun try to settle there - with the
intention of remaining for at least o ne year.
• Emigration - this is movement out of
one's country to settle in another country \'Vit h the in tention of remaining there for at
least one year.
The time 11 takes for a population to double 111 size can be
estimated by using the formula t = 70/r, \'Vhere t 1s the
doubling time in years and r is the rate o f population growth
expressed as a percentage.
The population change in a coun try is the result of natu ral
increase and migration, as f igure 2.3 .2 explains.
Calculating nat ural change
Barbcdos
BR
DR
f'vligrat on
Na tural change
Population change
= 12.0 per 1,000
= 8.4 per 1,000
= -0.3 per 1,000
= 12.0- 8.4 = 3.6 per 1,000
= + 0.36 % (natu ral increase)
= natura change (+3.6 per 1,000)
+/- migra tion (-0.3 per 1,000)
= 3.3 per 1,000
Carry out yoJr own calcJ ations for Trinidad and Tobago to find natural change and populat'on change.
BR
DR
f\l.igrat on
= 13.8 per 1,000
= 8.5 per 1,000
= -6.42 per 1,000
Population change - the demographic transition
model
Look at Figure 2.3.3. It is a graph that shows population change over
time. 11 is called the demographic transiti on model (demogrcphy
is the study of population). The demographic transition model (DTM)
shows the changes in birth rate (red line), death rate (bl ue line) and
total population (green line). It does not, however, take account of
migration.
Notice tha t on the graph i1 is possible to identify natural change
between the birth rate line and the death rate line.
Stage 1
{high
fluctuating)
Stage 2
(early
expanding)
Stage 3
(late expanding)
Stage 4
(low fluctuating)
Stage 5
(natural
decrease)
-
Birth rate (BR)
Death rate (DR)
Growth (NI)
Decline (ND)
- Total population
Total population
J------:::::t:=:::::=:::::4:::::::=
The future?
'-----'-------''-------'-------'-------►Time
Indigenous
Afghanistan
Examples people in
{
remote rainforests
Figure 2.3.3
Demographic transit on model
Most developing
countries, Including
the Caribbean
UK, USA,
Canada
Germany, Italy,
east European countries,
Japan
• Na tural increase (shaded pink) occurs w here the b irth rate is hig her
than the death rate.
• Na tural decrease (shaded blue) occurs vvhere the death rate is
higher than the birt h rate.
The demog raphic transition model shows the theoretical cha nges
that take place in a cou ntry's population over several hundred years
as ii becomes developed . 11 is possible to place a country into one o f
five stages according to its population cha racteristics.
Note that the demog raphic transition does not follow a smooth
movement along the various stages.
Demographic transition model stages
Stage 1
• Birth rate and death rate are both high
and fluctuating.
• s·rth rates are high owing to high infant
mortality, lack of birth control and need
for child ren to vvork on the la nd.
• Death rates are h igh owing to famines,
wars and disease.
F1gure 2.3.4
Stage 1 - Shuar famiiy of the Ecuador•an ra nforest
Stage 2
• Death rate starts to fall. Natural increase
rises as does the total population.
• Death rates fall as medicines are
introduced, healt h care improves, and
there are better diets and improved
living conditions (safe water and
sanitation) . Child ren are still needed for
labou r.
Flgure 2.3.5
Stage 2 - exiended family of fam,e" ,n At•Bashl, Kyrgyzstan
Stage 3
• Birth rate starts to fall rapidly, natural increase declines as does the
rate of total population growth. An increased standard of living
means that children go to school rather than work.
• Birth rate falls owing to reductions 1n infant mortality (better
medicines, vaccinations), decisions to reduce family size, women
entering careers and family planning.
Japan has the highest life
expectancy :n the world at
84.46 years (81 .13 years male,
87 .99 years female). Svvaziland
in Sou th Africa has the lov,est
hfe expectancy at just 49.98
years. n the Car:bbean,
Martinique has the h'ghest
hfe expectancy at 79,5 years.
(Data source: The CIA World
Faetbook 2015.)
Stage 4
• Birth rate and dea th rate now low and fluctua ting . Total population
levels off.
• Slight vanations reflect short-term changes, such as 'baby booms'
or economic gro\,vtl,/decline.
Figure 2.3.7
Stage 4 - co.Jp 1e and their two daughters
playing on the beach
Stage 5
• Birth rate falls below death rate and total population declines.
• Very low birth rates result from women's choice to follovv careers,
leading to them having child ren later, or not at all. Remember that
women's fertil ity reduces with age.
Most Caribbean countries can be placed towards the end of stage 3
or the start of stage 4. Notice that some countries, such as Japan in
stage 5, are likely to experience a decline in their future populations.
Population structure
Population pyramids
LEARNING OUTCOMES
• Understand the characteristics
of population pyramids.
• Compare popu ation
pyram ·ds for developed and
developing countries.
• Be able to interpret Car bbean
population pyramids.
The total populatio n o f an area, such as a country, a region o r a city
can be su bdivided into different age grou ps. It can also be divided
into male and female. This information can be plotted as a series of
horizontal bars to create a diag ram called a population pyramid .
Popula tion pyra mids can be used to identify trends in birth rates,
dea th rates and life expectancy. They are extremely useful to
governments for planning purposes, for example, in providing
enough school places for a g rowing populatio n or health care and
support services for an ageing populatio n.
Jamaica: 2014
-
MALE
10-0+
95-99
FEMALE
7%
as-as
Total population:
Dependency
ratio: 54
311-$0
2,930,050
15-19
(2014)
1~14
65-aS
60-.4
55-59
sn-s,
-'5-'-a
":l-44
35"'39
31)41
25-29
2-0-24
IS-19
10-14
5-9
0-'
165
132
Figure 2.4.1
99
66
33
0
0
33
Population (tnousand)
66
99
132
165
Popuiation pyramid for Jamaica
S¢u~f fr'ld~·Jndi Md T.'16' C.'/., 1-\~,'d F~l!X>Ct
Population pyramids can help vs
to understand populat,on trends
,n the pas1. For examp e, in
some Caribbean countries there
were high rates of emigration to
Europe 'n the 1960s. Most of the
emigrants were young persons
in the r 20s. By 2000, t hese
indiv'dua!s had reached the age
of 60. This explains why, in some
Caribbean countnes, the bars
for individuals in their 60s are
slight y shorter than expected.
.zo:s (Tota l 1>¢1>.1:,n ¢1'! tnd Oe<:onder(y(.tt◊ :;it~)
Jamaica's population
pyramid
Look at Figu re 2.4.1. 11
shov.,s Jamaica's populatio n
pyra mid . Motice that Ja maica
has youthful and young adult
popu lations with a high
proportio n of individuals
aged 0 -30 years. Vl/h1le there
has been a recent decline
in the birth rate, Jamaica's
popu lation d oes have a broad
lower half and narrow top,
which ,s typical of developing
countries. In the futu re, the
0- 30 ' bulge' of t he pyramid
\<Viii work ,ts \<Vay up, resulting
in a larger number of middleaged and elderly people.
Comparing population pyramids
Mow look at Fig ure 2.4.2 and compare the population pyra mids for
Nigeria (a developing country) and Australia (a developed country).
• In Migeria, t he very broad base indicates a hig h bir th rate and
suggests that the population is likely to rise in the future.
• In Australia, the narrow base indicates a low and stable birth rate.
• The roug hly parallel sides of Australia's population pyramid suggest
that life expecta ncy is high and the populatio n is fairly sta ble.
• Nigeria faces challenges associated w ith a high b irth rate and
rapid ly growing popula tion \<Vhereas Australia faces challenges
associated \'Vith an ageing population.
Nigeria: 2014
MALE
A1111rall1: 2014
FEMALE
10:,.
,,_.,
MAlE
91...tt
Tola.I p!!p1. i;o1:
117 15.5,75&
&1--84
:!-n
rJ-74
E!-et
i~4
!!-al
Ttt.i Olll)H1lon
Dape11e1,1c>'
rato: 8.9
8:4i
22,.107,61 7
1!-:t
......
:t-1'
:it-<4
&;-6;
i!-64
J;-4i
>!-!I
.....
,,_,,
::-a,
4-;-44
3;-3;
3:!~4
2!41
2-:44
! 5-ti"
4(~4
J~4
(f-lt
(t:-.(4
1!-19
...,..
,:,.,4
!J- !4
!◄
12
9
6
3
0
Oaper.:la:'IC)'
rato:SO
!::-!4
.,..,
15
fEM,\lE
10;.,
9!4i"
0
3
6
9
12
15
820
656
328
164
0
0
15'
328
492
656
P,11p-J:a:on (tn:11,..sa,,!ls;
Figure 2.4.2
Population pyramids for Nigeria and Austral a
SCv.-« :nd(Wt'lu.n~i and nie C!A t,-\~•'d i:-,t(ft):,¢,t
w: 5 (T¢ta popi. 61:0r. ll"ld 0,el)erdtl',tjl rb\iO dH!.11
Population pyramids and the demographic
transition model
Look at Figure 2.4.3 to see ho\,v the different stages of t he
demographic tra nsi tion model ca n be represented by population
pyramids. Notice that in stage 1 the population pyramid has a very
broad base and narrow top. By stage 5 it has been transformed to
have a narrow base w1th roughly parallel sides and a high broad top.
.. ------~---------------~--...--....... ___ ,........
The demographic transition model
....,
...
••
-
• ->-------1-- - - - - - - --t-----'----+ - - ' - --I-'
1,00
1740
Ullpn, 17t0
---
l?10
1120
~
17001101870
tribe>
Population
Pyramid shape
Agure 2.4 .3
Demograph,c transit on model and popula11on pyramids
19'0
lM Hl70 10 I950
IMO
l'ool1G50
UIC
Oo:athrttt
11 nh nte
--
DNhN h
,...,lctl...
Population growth
case studies
LEARNING OUTCOME
Jamaica: a developing country
• Com pare the demographic
trans tion models for Jamaica
and China.
In 2014 Jamaica had a total population of 2,930,050. Having
grown rapidly between 1950 and 2000, it is now growing much
more slowly, at a rate of just 0.7 per cent per year. The reduction in
population growth since about 1998 is the result of reduced natural
increase and the emigration of young adults and young families.
Look at Figure 2 .5. 1. 11 shows Ja maica's demographic trans"tion
model. Notice that Jamaica is currently towards the end of stage 3
in the model. The dea th rate has fallen and is now low and the birth
rate is falling too . When the birth rate starts to level off Jamaica will
enter stage 4. Here is some more information about stages 1-3:
• Stage 1 (1 900- 23). The birth
450
rate and death rate \'Vere both
Stage 1
Stage 2
Stage 3
high durung this period. Poor
~ 40.0
- Crude birth rate
living conditions and ou tbreaks
~ 35.0
- Crude death rate
of disease resulted in high and
8
0 • 30.0
fl uctuating death rates. Hig h
~
250
infant mortal ity and a need to
have child ren to su pport families
120.0
and work on the land accounted
=~ 15.0
for the high birth rates.
~ 10.0
• Stage 2 (1 923- 60).
5.0
Improvements in medicine and
better living conditions resulted
in a steady drop in the death
rate. The birth ra te remained
high and, for a short time, even
figure 2.5. 1 Jamaica's demographic transition model
increased bet,Neen 1952 and
1965.
• Stage 3 (1960-201 5, then beyond). Birth rates started to fall
during this period. Infant and child mortality rates fell due to
improvements in health care. full-time education resulted in
\'\/Omen choosing to follow careers rather than starti ng a family
at an early age. Contraception became more widely available and
more acceptable.
a
Look at Figure 2.5.2. It shows the expected changes in Jamaica's
population structure from 2000 to 2050.
• 2000-25. The narrowing bars at the base of the pyramid suggest
that the birth rate wil l fall. The bars towards the rriddle and top of
the diagram are becoming wider suggesting a low death ra te and
increasing life expectancy.
a 2000
,✓.ale
200
Femalo
Ag,
150
100
50
0
0
Pcp-.i.ato11 i!nt-iousao:ls;
50
100
; 5-0
200
b 2025
,.~ale
200
C
.
150
100
50
'
0
Female
0
Pcp-.i.ato11 i!nt-iousao:is;
50
100
; 5-0
200
2050
,.~ale
Female
'
19
O+
•
j
!9
i
1,.,
200
150
Figure 2.5.2
100
50
0
0
50
Pcl)J.a.;o:i {Intr.ousaodsl
100
15-0
200
Popslat'on pyram ds for Jamaica
Soo.1•:e lnde111"1'1u.itli
• 2025-50. The birth rate becomes low and stable by 2050. The
population becomes older, with more individuals living to middle
and old age. This is now a typical developed world population
pyramid. In the future, Jamaica 'Nill have to cope with issues
associated with an ageing population.
China: a rapidly growing economy
China is an increasingly wealthy country in eastern Asia. As the
largest population in the world, it had 1.35 billion people in 2014.
Its pattern of grO\<Vth has not followed the demogra phic transition
model very closely.
I
I
Stage 1
Stage 3
1,400
1,300
1,200 11
0
1,100 ~
C
1,000 .s
:~~
700
600
500
i
Year
-
Fi ure 2.5.3
Binn rate
Death rate
Total population
"' Total population at certain dates
China's demographic traos1ion model
S¢1.itCt, ,.l,!i1¢(1 li.bC
Figu re 2,5 .3 shows China's progress through its demographic
trans'tion, w hich is rather different from Jamaica's experience on
page 124.
• Chma vvas in Stage 1 until around 1960. Children vvere importan t
as they were needed to work the land. The Communist government
provided reasonable heal th care. The b irth rate vvas high and the
natural increase rapid . Rapid industrialisation took people off the
land and the food supply reduced . In the resulting devastating
famine almost 30 million people died of starvation. The death rate
rose and the birth rate fell, g iving a period of dramatic natural
decrease.
• Aher the famine China moved into stage 2 \<Vith a baby boom and
rap,d natural increase. The government \<Vas concerned that the
population would again outgrow resources, so in 1979 the onech ild policy was desig ned to reduce family size (see Figure 2.5 .4).
The policy included these measures:
- Later marriage \<Vas encouraged, leaving little time to have
children .
- Only one successful pregnancy \<Vas al lo\,ved .
- Sterilisatio n after t he f irst child was often forced .
- Very late abortions were performed .
- Couples w ho obeyed the rules were given benefits; those who
did not were financially penalised .
• China's birth and death rates are now low and stable and it can
be classified as a stage 4 country. Soon 1t will be overtaken in
popula1ion size by India.
• Sons were preferred and
some girls vvere abandoned
or placed in orphanages.
Some were adop ted by Bri1ish
and American couples.
• Chinese children are
somet mes called 'Little
Emperors' because many
are over-indulged as only
children.
China: 2000
70 60 50 40 30 20 10 0
0 10 20 30 40 50 60 70
Population (In millions)
China: 2007
Female
Male
70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 70
Popula1lon (In millions)
China: 2025
Female
Male
70 60 50 40 30 20 10 0 0 10 20 30 40 50 60 70
Popula1lon (In millions)
Figure 2.5.5
Here are some of the results of
Ch'. na's one-child policy:
Popclat,on pyram:ds for China
SOuf"'J l;idtxmufldi
• Today a gender imbalance
exists - young men have
trouble finding a wife.
• G;rls are now valued as much
as boys and urban women
especia ly are very careerfocused .
• China will soon become an
ageing population and more
young people are needed to
1ook after the elderly. Since
China overturned is onechild policy in late 2015, the
number of couples having
two children has prog ressive,y
ncreased.
Urbanisation in the
Caribbean
LEARNING OUTCOMES
• Understand the causes of
urbanisa t1 on.
• Understand the 1rends and
Impacts o f urbanisation In the
Caribbean.
Wh at is urbanisation?
Urbanisation is the growth in the proporfon of individuals living
in to\,vns and cities. Urban growth is the increase in the number of
u rban dwellers.
In 2011, 56 per cen t of people lived in towns and ci ties; in 1960 the
fig ure vvas 34 per cent. By 2030, an estimated 60 per cent of the
world's 8 .1 billion inhabitants are expected to be urba n dwellers.
However, this figure varies enormously from country to coun try.
.
EXAM TIP
Singapore 1 - -....- . . -.....- - . - - . - - . - - ,, . -....- - -
UK ........_..__,,___.__..__.._ _._....,_-,1
•
Australia..__.___._ _.__ _.__.__._ _.__....__,
Canada ,__ _ _ _ _ _ _ _ _ _ _ _
' __,
~t/01,tY i;IQt:Q
.
~lob&1l 1<Yb&1.,._ popul&1t[o""
LS expecte~ to g Yow
&1v.111,u&1llt:J bt:J:
Cubat-_....,..,.._.,.__
Jamaica
'
_.__.__.=,,....-,,
>---~-~-...----'
• 1 -8 peY cevct betwee ....
::2015 &lvcd ::20::20
Nigeria {:::::::!=:::I=::C:::::!:::;-j
China {:::::::!=::r::::::r
_.,
• 1 .7- pe1• cev.t betweev.
Guyana-t=::r=r""''
::20::21 &1i,,,d ::20::25
• 1 -4 peY cev.t betweev,,
::20::2b &I vcd :::2030.
Note tl1e tYev.d
ti1ese d&1to1 .
sl-iowv.
bl::/
Burkina Faso -l==:==f0
10 20
7
--l-- -l---l---l---1-- -4--- -l-----1
30 40 50 60 70 80 90 100
% urban population
Figure. 2.6.1
I Per.cemage urbanisation in selected countries
The steady increase in u rban populatio n arises from two factors:
1 Rural- urban migration, as individuals seek to improve their
lives by moving from the coun1ryside 10 to\,vns and cities.
2 Rapid natural increase in urban areas, usually owing to the
influx of young couples from rura l areas. These are people in
their child-bearing years. Towns and cities usually have a younger
population than rural areas.
Rural- urban migration
Most individuals w ho move from rural to u rban areas choose
to do so . They \'Veig h up the advantages and disadvantages of
such a move. It is possible to identify push factors and pull
factors (see Figure 2.6.3):
• Push factors - these are negative aspects of rural areas
A young fam ly in a squatter town n
'--"--,._....,.., Cambodia
1hat encourage indiv"duals to move away, for example
crop failure, poor standards of living, poor services and
infrastructure, lack of educa1ional and employment
opportuni1ies, and limited enter1ainment.
• Pull fa ctors - these factors draw individuals
to,Nards a town or city, rather li ke a magnetic
force. They are posi tive factors and include
better opportunities for education and heal th
care, better-paid jobs and wider choices of
entertainment. Often these advantages are what
ind ividuals think will be available - they may well
be disappointed when the reality turns ou t not to
be quite so good I
Urbanisat ion in th e Caribbean
Look at Figure 2 .6.4. It uses pie charts to shov; the
levels of urba nisation in the Caribbea n. Notice that
some countries are more urbanised than others:
Figure 2.6.3
Push and P•II factors
• In Cuba, Martinique, Puerto Rico and Trinidad and
Tobago, over three-quarters of t he population live
in urban areas, mostly in the capital cities.
• In con trast, less than half the populations of Haiti, St Vincent,
Guyana, Montserrat and Antigua and Barbuda live in urban areas.
Compared to the rest of the world, the Caribbean region has high
levels of urba nisation. In 2000, just under 50 per cent of the world's
population lived ·n tovvns and cities whereas m the Caribbea n the
figure was nearly 65 per cent. By 2025, the urba n population in the
Caribbean is expected to rise to 76 per cent.
!lapa~ as ~
~
Turks and
Caicos Is.
-... ,.
----.
.
~~~
)·~
. Cuba
.""i
- - ~omlnican
•
Republif
.
<C:>
Q)
Jamaica
Haiti
Cayman Is.
0
Puerto
Rico
,.,,
•
Virgin IS
(USA)
and Nevis
Guadeloupe
•-~ ~
' ....----\
..____,.,
Martinique
g
Montserrat
N
Netherlands
Antilles
Q)
Agure 2.6.4
%urban
population
(orange portion)
..,
:
,
~~rbados
Trinidad
~
1 and Tobago
I
,:
J
i
-..:..-.......ud-
\ _ _
1
Levels of urbanisation in the Caribbean
500
Antigua and
Barbuda
~ \. .,
V
St Kitts
km
t
Mana
...__ _,
'
Impacts of urbanisation
Urbanisa tion has impacts on both rura l areas and towns and ci ties.
Impacts on rural areas
The high rate of ru ral-urban migration has led to a fall in the
population in many rural areas in both the Caribbean and in other
parts of the world. This is cal led rural depopulation.
Rural depopulation can bring advantages - \,vith fewer persons there is
less pressure on limited resources, such as food, water, employment and
shelter. However, it often creates problems, for example:
• An ageing population - mostly it is you ng men or couples who
move to urban areas in search of better opportunities, leaving the
older individuals behind.
• Decreasing food production - older individuals are less able
to cope \'Vith the physical demands of farming so production may
decrease.
• Loss of services - as the population reduces, some public services,
such as schools and transport, may be affected. Shops may
close wi th fe\,ver customers living in the area. As services decline,
more individuals will be tempted to move away and so the cycle
contmues.
Impacts on urban areas
The rapid in flux of newcomers to towns and cities has provided
much-needed labour and crea ted a thriving market for goods and
services. Ho\,vever, it has also brought with it these problems:
Around 8 per cent of the world's
popula1·on live in massive cities
called 'megacilies'. A megacity
is defined as a city with a
population of over 10 m'llion.
According to the un;ted Nations,
the world's largest megacity
is Tokyo in Japan, w;th a
population of 38 million ·n 2016.
• Urban sprawl - this is the physical growth of t he city at the edges,
mostly caused by more and more people needing housing. Urban
sprawl can destroy valua ble farmland and natural vegetation d ose
to the city.
• Lack of appropriate housing - housing shortages have led
to the development of poor-quality housing areas, sometimes
called squatter settlements. Here the houses are poor quality and
residents of1en have inadequate services, such as education and
health services, access to \'\later. \,vaste disposal and sanitation .
• Urban poverty - the reality of city life may not live up to
expectations and some individuals are unable to get a job. The level
of poverty in urban areas is hig h.
• Transport and congestion - transport systems may fail to cope
\,vith the sheer number of persons so 'all-day rush hours' may result
as vehicles clog the narro>N streets.
• Crime - levels of crime can be high in some ci ties, particularly
\,vhere there are hrgh levels of poverty, alcoholism and drug abuse.
Primate cities
Country
One characteristic of urbanisation
in 1he Ca ribbean has been the
concentration of persons into a
single urban area . This is sometimes
called a primate city.
A primale city has a population of
al leas t 1wice t hat of the next largest
ci ty. In most Caribbean cou ntries,
over 30 per cent of the population
live in a single prima te city, which
·s usually the capital. Figu re 2.6.5
lists the prima te cities in Jamaica,
Barbados and Antigua. Notice
how much larger they are than the
second cities.
Largest city
Second city
Name
Population
Name
Population
Jama ica
Kingston
584,627
Portmore
182,153
Barbados
Bridgetovvn
99, I 00
Speightstovvn
3,600
Antigua
St John's
24,45 1
All Sain ts
Figure 2.6.S I Selected primate cifes 'n the Carbbean
3,900
Prima te cities can cause an
'mbalance of investment, resulting in
the formation of a thriving economic
core area based on the primate city
and a relatively poor, more rural,
periphery. In an ideal world, it is
good to balance ou t development
over the vvhole of a cou ntry.
Urban
Country Population Rank Population
2014 (OOOs) 2014 2030 (OOOs)
agglomeration
Rank
2030
Tokyo
Japan
37,833
1
37,190
1
Delhi
India
24,953
2
36,000
2
Shanghai
China
22 ,991
3
30,751
3
.....,
lfl(Offl,e
Mexico City
Mexico
20,843
4
23,865
10
Sao Pau lo
Brazil
20,831
5
23,444
11
Mumbai
India
20,741
6
27,797
4
Osaka
Japan
20,123
7
19,976
13
Beijing
China
19,520
8
27,706
5
1cono,nk
9,0....'ffi
lnM1u,111y
'
•
...
, .,
1ifo,d1bl•
ho-.sln,g
Pove,cy
'
lfl<m~H rillfl
•
'
. . .ffl
lom u1d M
New York/
Newark
USA
18,591
9
19,885
14
Cairo
Egypt
18.419
10
24,502
8
Flqure 2.6.7 I Top 10 megacity popu lations and rankings (201 4) with predict,ons
to 2030
Figure 2.6.8
lnequal1y povert>/ and
slum format on
~V.'<'f,
The <;hafit-:lgtol s.'v~s.
LN, 2COJ
Problems of urbanisation
in the Caribbean:
Kingston, Jamaica
Kingston: a primate city
LEARNING OUTCOME
Jamaica's capital city, Kingston, is the largest city in the Englishspeaking Caribbean \<\11th a population of 584,627 (2011 census). Over
30 per cent of the population of Jamaica live in Kingston . It is a classic
example of a primate city, being more than three times larger than 1he
second city, Portmore.
• Understand the causes and
impacts of urbanisatio n in
Kingston, Jamaica.
Problems caused by urban
growth
The location of Kingston
The city of Kingston lies o n the coast of the bay of Kingston in the
south-east of Jamaica. Look at Figu re 2. 7 .1. Notice that the city is sited
on relatively flat land bounded by mountains to the nort h and east, and
the sea 10 the south . M uch of the land to the 'Nest is heavily wooded
and swampy. The Palisadoes spit has created an excellent natural
harbour, which is one of the main reasons for the growth of the city.
The problems o f urban growth in
the Kingston built-up area nclude:
• development o f squa tter
settlements -1he Global
Housing Policy ndica tors repor1
of 2011 shovved that 20 per
cent o f households m the
Greater Kingsto n area ived in
nforrnal sq uatter settlements
Population growth in Kingston
The population of Kingston has grown rapidly from 379,980 in 1960 to
its current level approaching a million . This is mainly the result o f:
• substandard housing
• hig h rates of natural increase (birth rate of 22 per 1,000 and dea th
rate of 6 per 1,000)
• rural-u rban migration .
• high ren ts for the qua ity of
hous ng available
• overcrowding
In recent years, migration from the countryside has decreased, wi th
natural increase being the main cause of Kingston' s growth . Emig ration
rates, particularly to the USA, are quite h igh. Withou t this, 1he rate of
Kingston's gro\<Vth would be even hig her.
• nadeq uate transport networks
• environ mental deg radation
• high crime rates.
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Locat'on of Kingston
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Kingston's urban landscape
As the popula1ion has increased, Kingston has expanded physically 1o
cover much of the ligua nea Pla in (see Fig ure 2. 7.2) and is expa nding
into the foo1hills of the Blue Moun tain range.
Kingston is divided into several d ifferent districts . To identify these,
locate Cross Roads o n the map shown in Figu re 2.7.1.
• To 1he south is Downtown, mostly comprising 1he harbour,
industrial areas and lov,i-income housing. Th is is the busiest part
of the city, wi th many retail and commercial enterprises, and many
government offices. Some of the housing in districts such as Trench
Town is low q uality, being poorly maintained and often subdivided.
This is where a building that was originally occupied by a single
family has been converted into flats or apartments to house several
famil ies, each with only a small amount of living space.
Figure 2.7.2
Liguanea Plain, Kin.9s1on
• To the north is Uptown, which is mostly made up o f modern
offices, entertainment, restau ran1s and higher-income housing.
The area known as Ne\,v Kingston is popular with tourists.
Downtown Kingston is characterised by a grid-square road layout.
However, as the city has expanded ou t\,vards (urban sprawl) to engulf
smaller villages, this regular street pa ttern canno t be found o n the
outskirts of the city.
The city of Kingston can be called a conurbation since its g rowth
has engul fed former free-sta nding towns and villages.
Problems of urban growth in Kingston
While the gro\,vth of Kingston's population has provided muchneeded labour for industrial development and a huge market
for goods and services, it has led to a number of social and
environmental problems :
• Housing poverty - many individuals live in cramped and
poorly maintained houses in the Downtown district of the city
(see Figure 2.7.3). Up to a quarter of Kingston's popula tion is
unemployed, w hich means that they have very little money to
spend on home improvements. Crime is w idespread, often related
to drug abuse. Despite some attempts to improve housing, such as
loa ns from the National Housing Corporation, many individuals still
live in poverty.
• Urban decay - a number of build ings in the Downtown distric1
have been poorly maintained and have deteriora ted. The governmen t
has responded to the issue by redeveloping the waterfront, which
was completed in 1975. In the 1980s, 1he Urban Development
Corporation upgraded Parade Square and since 1995 the Urban
Renewal Tax has funded additional improvemen ts in the area.
• Transport - congestion and pollution have been a problem for
many years. Older cars are often poorly main tained, adding to the
problems of air pollution. New roads constructed for commuters
have increased the number of cars funnelled into Kingston 's dense
city-centre road network. Despite investment in public transport,
transport remains a ma1or issue in Kingston .
Kingston is home to three of
Jamaica's largest ne\<Vspaper
companies, several television
and radio stations and sports
stadiums, inc uding the famous
Sabina Park cr:cket ground.
Indeed, Jamaica is referred to as
the 'Holiday Horne of Cricket' 1
The g reat Sir Garfield Sobers
scored 365 not out at Sabina
Park aga ns1 Pakistan n 1958.
Jamaica ,s also referred to as the
' Track capital of the war d' as 1t
is the training ground for three
of the fas1est men in the world.
Controlling urbanisation
in the Caribbean
LEARNING OUTCOMES
• Understand the problems
associated with urbanisation.
• Understand the options for
solving the problems, with
reference to Barbados, Trin dad
and Tobago and CJba.
Wh at are the problems of urbanisation?
Urbanisa tion can cause a number of problems:
• As city popu lations increase there is pressure on jobs, housing and
services.
• Cities face increasing pro blems of unemploymen1, crime, building
decay, congestion and pollu1ion .
• The growth of a single primate city often leads 10 inequali1ies
\'Vithin a coun1ry.
• Rural areas su ffer from pro blems of rural depopulation such as lack
of investmen1 and an ageing population .
Green be ts have been used
to control urban sprawl in
the UK from the 1940s,
around cities such as London,
Birmingham and Manchester.
n England 13 per cent of
the land is offic°a lly green
belt. Deve•opment in green
belts is restricted, parfcularly
around London . This has led to
developments ' leapfrogging' the
green bell to take pace in land
just over the other side in towns
called satellite towns.
,, CASE STUDY
How can these problems be solved?
Countries in 1he Caribbean have tried to address 1hese pro blems by:
• Decentrali sation - encouraging new developments to ta ke place
away from ca pital cities, thus reducing primacy.
• Green belts -1he use o f planning measures to crea te a ' green
belt' around ci1ies \'\/here development is restricted . Not o nly does
this prevent u rban sprawl bu1 it helps to protect farmland and
conserve w ild life.
• Investing money in rural areas - improving services, transport
and living conditio ns so that people will choose to stay and work in
the countryside ra ther than moving 1o towns and cities.
I Ba1bados and Cuba
Barbados
In Barbados, a series of Physical Developmen1
Plans (1970, 1986, 1998 and most recently
2003) have at1empted to reduce the inland
physical g rowth o f 1he capital Bridgetown and
encourage 1nvestmen1 in the countryside.
• The designa1ion of the existing communities
of Spe1ghtstown, Hole10\'Vn, Oistins and Six
Cross Roads as Regional Cen1res. They vvill be
developed as mixed-use centres, wi1h housing
and commercial developments be;ng permitted.
The main features of t he 2003 Development
Plan are as follows:
• Investment in other smaller se1tlements
outside the urban corridor (rural settlements
wi th grow1h po tential), such as Ellerton, in an
a ttempt to reduce rural depopula1ion.
• The des·gnatio n of an urban corridor
along the south and west coast of Barbados
that includes Bndgetown and other major
settlements. It is within this zone 1ha1 mos1
new developments \'Viii be concentrated.
Notice on Figure 2.8.1 that the urban
corridor will prevent t he inland expansion of
Bridgetown .
• Some housing and commercial developments
will be permitted in villages \'Vithin the Na tional
Park, such as Ba thsheba .
• In an attempt lo boost farming and reduce rural
depopula tion t here will be opportunities for
people to buy land to establish smal l farms.
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Figure 2.8.1
Physica Deve opment Plan for Barbados (2003)
Cuba
The Cuban government exerts much greater
control over the lives of its people t han happens
elsewhere in the Caribbean, and policies here have
tended to be more successful. Since t he 1960s the
government has invested heavily in educational and
welfare programmes in the countryside to reduce
the flow of individuals to the capital city, Havana.
The focus on improving schools, heal1h clinics and
agriculture in rural areas has been very successful in
reducing rural depopula1ion (see Figure 2.8. 2).
Figure 2.8.2
Rural de·,eloprnents in Cuba
aI
International migration
in the Caribbean
LEARNING OUTCOMES
• Understand the types and
causes of migrat on .
• Understand the 1rends In
migrat;on In the Caribbean.
• Understand trends of
immigration and em·gration
in the Cayman Isl ands and
Jamaica.
What is migration?
Migration is the movement of individuals from place to place. 1/1/hile
some forms of migration are short term, such as commuting to work
or going on holiday (which is called circulation), the term is usually
applied to those w ho move to a new place, often in a new country,
with the intention of remaining there permanently o r for at least a year,
Most migration is voluntary. Individua ls weigh up the advantages and
disadvantages before deciding to leave one place and move to another.
Often th:s is to do with employment or the desire lo live closer to
rela tives. However, some migrations are forced. These may result from
a natural disaster, such as an earthquake o r volcanic eruption, o r they
may be the result of poli1ical persecution and 'e1hnic cleansing '.
Individuals who move out o f a country are called emigrants.
Ind ividuals who move into a country are called immigrants.
EXAM TIP
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t i1e cli.ffeYevcce betwee.,,
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Canbbean immigrants to the
UK, USA and Canada have
introduced a rich cultural
heritage, including reggae
music, fashion and cooking,
such as Caj un and Jerk d 'shes.
In the UK, 1he annual '\Jotting
Hill Carnival is a ce' ebra tion of
West nd ian culture and heritage
centred in the Notting Hil district
o f London. Traditional steel
bands and colourfu floats crea te
a vibrant Caribbean atmosphere
1n the centre of London, and
hundreds of food stalls line the
streets. Millions of people from
around the \,;ortd are attracted
to the carnival each year.
International migration in the Caribbean
The Caribbean has been greatly affected by interna tional migratio n
for hundreds of years.
• During the colonial era from abou t 1500, many individuals from
Spa in sett led in t he Ca ribbea n. They broug ht wi th them A frican
slaves to work on pla ntations.
• The Spanish were follo\,;ed by the Bri tish, French and Dutch \,;ho
later colonised t he isla nds in the Caribbea n.
• Following the abolition of slavery in 1834, there were large-scale
movements of people wi thin the Caribbean from Barbados and
Jama ica to less popula ted countries such as Guya na and Trinidad.
In recent decades individuals have moved from Haiti, the \,;estern
hem isphere's poorest country (which also suffers from earthquakes
and hurricanes) into the neighbouring Dominica n Republic to work
on the suga r cane plantatio ns.
• Du ring the 19 50s, many West Indians decided to move to the UK
and other European countries in search of work. In the 1961 UK
census, over 170,000 Caribbean-born people were fou nd to be
living in the UK compared wi th Just 15, 000 in 1951.
• In the 1960s, changes to the immig ration la~vs in the USA and
Canada made migration from the Ca r'bbea n easier. In 2000, there
\,;ere nearly 3 million Caribbean-born persons living in the USA,
mostly in the states of New York and Florida . Most had travelled to
the USA in search of work or education, or to buy la nd.
• More recen tly, there have been several major developmen t projects
in the Caribbean funded by China and other As'an countries, such
as improvements to Kingston's harbour and 1he construction of a
cricket ground on Dominica . During construction, Chinese workers
\,;ere broug ht to t he Caribbea n, and they then returned home
\,;hen the con tract was complete.
CASE STU DI ES
Cayman Islands: high immigration
The Cayman Islands has the highest rate of immigration in the Caribbean . Recen t economic growth,
particularly in tourism, construction and financial services, has resulted in a rapid expansion of
employment opportunities. Between 1970 and 2014, the population grew from 10,068 to almost 55,000.
Most of the immig1a nts to the Cayman Islands have come from nearby Jamaica where there are fewer
o pportunities for employment. Increasingly, the Cayman Islands is a 'halfway house' for Cubans wishing
to migrate to the USA.
Immigration has brought
weal th and development to
the Cayman Islands. However,
there has been a negative
impact on the environment,
particularly widespread
deforestation.
Jamaica: high emigration
In contrast to the Cayman
Isla nds, Jamaica has
experienced one of the most
rapid rates o f emigration in
the Caribbean . An estimated
2.6 million Jamaicans live
abroad - a similar number
to those currently living
in Jamaica. The grea test
concentrations are in the
USA, Canada and t he
UK. The main reason for
emigration has been to seek
better o pportunities for
employment.
• UK - most emigra tion
took place In the late
1950s before the 1962
Immigratio n Act in the UK
restricted immigration . from
F1gure 2.9.1
Workers from foreign countries In the Cayman Islands
the late 1960s some o f the
immigrants moved back to Jamaica, although a large number still live in the UK.
• USA- over 173,000 Jamaicans were admit ted into the USA between 1991 and 2000. Most live in t he
urban centres, such as New York and Miami.
• Canada - most Jamaicans are concentrated in Toron to.
The emig rants have broug ht benefits to Jamaica . Many send or remit money home to their families. This
money is added to the economy and can be used by family members to start up businesses. Indirectly,
emigration has reduced pressure o n jobs and social services in Jamaica.
Economic sectors in
the Caribbean
LEARNING OUTCOMES
• Understand the four sectors
of econo,ric activity.
• Understand economic sectors
In the Caribbean.
Wh at is economic activity?
Economic activity is the vvay that individuals and countries
produce, distribute or consume products or services. Economic
activity provides the money needed for governments to spend on
services such as health and education, water and electrici ty as well as
for bu ildmg roads, hospitals and schools (infrastructu re).
11 is possible to identify four main types or sectors of economic activity:
1 Primary sector - this involves the extraction of raw materials
from the earth, for example farming, quarrying and fishing.
2 Secondary sector - this involves making (manufacturing) products
using the raw ma terials from the primary sector. Examples of
secondary industries include food processing, e.g. taking sugar cane
and processing it to make suga r. Clothes made from cotton and
cars made from steel and other raw materials are also examples of
secondary sector industries.
3 Tertiary sector - these are economic activities that provide a service to
people. Examples of workers in the service sector include teachers, shop
workers, hotel staff, health care providers and the police.
4 Quaternary sector (finance, trade, research and development,
advertising, consultancy) - this sector involves individuals who
provide information and expertise for others to use. This may
involve training, consultancy and research and development. A lot
of individuals working vvith information technology are included
in this sector. This is a relatively recent sector and is really just a
bra nch of the service (tertiary) sector.
Importance of economic secto rs in selected countries
Look at f igure 2.10. 1. It shows the importance of the economic
sectors in some selected countries according to their contribution to
the wealth of the country (gross domestic product - GDP). Notice
that the information is arranged in a slightly different way, using
agriculture, ·ndustry and services as the main
Composition of GDP(%)
types of economic sector. Figure 2.10.2
Country
Agriculturi. Industry* Services
shows the employment in each sector.
Jamaica
7
29
64
• For most countries, the service sector is
14
Barbados
3
83
the most important. In the Caribbean,
Trinidad and Tobago
1
57
42
many individuals are involved in tourism.
In countries such as the UK large numbers
Guyana
21
38
41
of individuals vvork in retailing and in the
Canada
2
28
70
fi nancial sector.
China
10
45
45
• Industry is the dominant sector in Chi na,
UK
1
20
79
where many people are involved in the
India
17
17
66
manufacturing of clothing and electronics.
Nigeria
31
43
26
In Trinidad and Tobago, a lot of wealth is
Flaure 2.10.11 Econom ·, se,...'"tors by contribution to GDP
generated by the oil and gas industry, food
..
• Includes m1n1ngtf,shing
processing and in manufacturing cement.
• In the Caribbean, agriculture is an
important sector in Guyana. It is less
importa nt in Jamaica, Barbados and
Trinidad and Tobago.
• Figure 2.10.2 shows that develo ped
countries, such as Canada and the
UK, have few people 'Norking in 1he
agricul tural sector. They also have large
service sectors. Poorer coun tries, such
as Bangladesh and Ethiopia, are very
dependent o n agnculture and have much
smaller service sectors .
Economic sectors in the
Caribbean
Country
Jamaica
Barbados
Economic sectors by employment(%)
Agriculture Industry•
17
19
10
15
Services
64
75
Trinidad and Tobago
4
33
63
Guyana
30
27
43
Canada
2
19
79
40
27
33
1
25
74
45
30
25
B
12
China
UK
Bangladesh
Eth iopia
80
Fiaure 2.10.21 EconomJC sectors by employment
.
"' Includes m1n1ng/fishmg
Primary sector (raw materials)
The prima ry sector has traditionally been very important in the
Caribbean:
• In farming, productio n of 1raditional crops, such as sugar cane, has
been widespread and still employs many workers in coun tries such as
Jamaica and Guyana.
• Fishing employs many people throughout the Caribbean.
• In Trinidad and Tobago, oil and gas is an extremely important source
of income and employs abou t 20,000 people (see f igure 2.10.3).
ure 2. 10. 3 Eimact.on oi o I in
Tonidad and Tobago
Guyana is o ne of the poorest countries in the Caribbea n. It still has a
large number of lo~v-income individuals working on the land owing to
the lack of modern machinery.
Secondary sector (manufacturing)
By adding value to raw materials (by processing them), such as food
products and fish, the secondary sector provides important export
revenues for coun tries in the Caribbean . Trinidad and Tobago has o ne
of the largest secondary sectors in the Caribbea n. This is the resul t of
the process'ng of foods, oil and gas, and the manufactu re of cement.
Elsewhere, food processing (see Figure 2 .10.4) and the manufacturing
of clo thes are important industries in t he Ca ribbean.
Tertiary sector (services)
Tourism is a rapidly growing industry throughout the Caribbean. 11
provides an important source of income and generates a large nurrber o f
jobs. Retailing also employs a lot of individuals and increasing numbers
are vvorking in public services, such as education and health care.
Quaternary sector (information and expertise)
The provisio n of in forma tion, together \'Vith activi ties such as research
and training, is increasing in the Caribbean. One recen t development
has been the creation of call centres, where individuals ring for
advice about banking, t ravel, insurance o r cellphone services. M odern
technology means that call centres can be located almost anY',vhere in
the world . One reason for the growth of call cen tres in the Caribbean is
because wages are lower than in countries such as the USA or the UK.
Flgure 2.10.4 A citrus process ng
.:actor/ in se:1ze
Resources and their
locations
Renewable and non-renewable resources - what
are the differences?
LEARNING OUTCOMES
• Understand the loca tions of
resources n 1he Caribbean
• Understand the factors
affecting 'ndustr al ocat on.
Renewable resources are 1hose which can be used repeated ly -1hey
are infinite and therefore do not run out. There are two types:
• A flow of nature- w 'nd, tides, waves and the su n provide
renewable energy.
• Living things - trees, ecosys1ems and soil are renewable as long as
people do not use them faster than they ca n be replaced.
No n-renewable resources, o n 1he o ther hand, are finite - 1hey will
run out. Examples include coal, oil and na1ural gas, and m inerals such
as gold and bauxi te.
Technology and simple com mon sense can help people extend the
use of both types of resou rce. Here are some examples:
• If fish stocks are over-used, fishermen ca n be excluded from certain
areas to allow regeneration . In the Euro pean Unio n there are rules
on the size o f fish that can be caught - small o nes must be thrown
back to mature.
• Selec1ive cu tting in rainfores1s allows the w hole ecosystem 1o
remain vvhile exploita tion takes place.
• Soil needs to be looked after to prevent erosio n.
• High- tech mining equ ipment allows previously inaccessible coal in
the UK to be mined . Improved oil explo ration has revealed new,
previously un known su pplies globally.
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Figure 2.11 .1
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-
Examples of
resources in the
Caribbean
..
In the Caribbean,
agricultu re and natu ral
resource extraction
are the basis of many
islands' economies.
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Survving Carbbean forests
@
•
•
Forests
f igures 2. 11 .2 and
2.1 1.3 sho,,v forest and
farmland resources in
Guyana and Jamaica .
f orest is scattered m
Jamaica but is found in
sufficient areas to be
sustainably exploited .
Guyana has large areas of forest. much of which is
tropical rainforest.
Fishing
Fishing is carried out across the Caribbean region,
using trawling, lines, seining (boats dragg ing huge
nets behind them) and pots for shellfish, largely for
the home market. Care needs to be taken to conserve
resources.
Oil and natural gas
Oil and natural gas exploita tion is particularly
important to Trinidad and Tobago as well as in Cu ba
and to a lesser extent to Barbados (see Figure 2.11.4).
Trinidad is the Caribbean's largest producer of oil
and gas. BP (British Petroleum) is t he main corr pany
involved . In terms of gas, Trinidad and Tobago is
becoming a major global gas centre. In addi tion
to the three countries shown m Figure 2 .11 .4, the
Figure 2.11.2
Bahamas may have 4 .3 million barrels of oil (according
to the US Geological Survey 2012). There may be
gas resources off Aruba and Costa Rica, thoug h
exploitation in Costa Rica is unlikely due to environmental
risks.
Proven resources
Crude oil (million
barrels)
Trinidad and Tobago
716.0
Cuba
750.0
Barbados
2.5
To tal Caribbean
1468.5
Figure 2. 11 .41 Caribbean 011 and natural gas reserves
Proven resources
Natural gas (billion
cubic feet)
23,450
2,500
5
25,955
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Bauxite
Bauxi te (or alumina - alumonium oxide, Al20 3) is the ore of the
metal, aluminium. It is an important global resource and the
Caribbean is a key location. Bauxite needs to be heated to 600'C
to extract the metal and this takes a huge amount of energy.
Bauxi te is processed to a limited extent 'n the Caribbean but much
·s exported to cheap energy locations such as Iceland with its
geothermal and hyd roelectric power. For Jamaica, this is the second
most important foreign exchange earner. Jamalco and Alcoa are key
compa nies.
Tropical ra1nfores1: in Ocho Ros, Jamaica
Lim estone
Limestone is quarried primarily for making cement
for the construction industry (see Fgure 2.11.4).
There is considerable demand for this as tert'ary
and quaternary bus;nesses need new buildings.
Jamaica, Barbados, the Dominica n Republic, and
Trinidad and Tobago all have such businesses.
Rock being blasted out of the landscape
causes considerable sca rring. It is essential to
have contracts that include a commitment
to regenerate the landscape to its previous
appearance.
Figure 2.11 .5 L,mesione In a quarry 1n Port-au-Prince,
Hait
industry aims to cut costs by
being as close to its resources
and raw materials, labour and
market as possible. The heavier
and bulkier the inpu ts and/or
outputs, the closer they need
to be to the other hubs of
the industry. Here are some
examples:
Gold
Jamaica vvorked gold deposits until 2005. More
recently Hispaniola (Haiti and the Dominican
Republic) has been the importan t loca tion for gold exploitation.
Hispaniola is bisected by a cen tral ridge of high land containing
precious metal deposits in both countries . The two key mines are:
• Mont Orga nise in Haiti
• Pueblo Viejo in the Dominican Republic (see Figu re 2. 11.6).
Other, smaller compa nies continue to search for viable mines.
Canadian companies are interested in mining in the Dominican
Republic, but the mining process threa tens the very environment
• Limestone and bauxi te are
heavy and it is cheaper to
carry them by sea .
• Vegetab1es such as yams need
to be c ose to market as t hey
are heavy compared to most
other vegetables and are
therefore more expensive to
tra nsport.
• Crops that detenorate quickly
also need to be near the
market.
• Oil and gas are transported
via pipelines, \<Vh1ch are
expensive to construct but
efficien l to run .
'
_.-'I
Sin Francl1eo )
de Macofit
Santiago •
Domi nican Republic
La Ve9a •
HAITI
•
~
It_
IP:-u-,eb.,..lo-:'VieJo
<'.
goldmine]
Santo Domingo
san c,1a16btl ~ • -
•
CARIBBEAN SEA
Figure 2.11.6 Location of Pueblo Vejo goldmine in the Dominican Repvbl c
that supports tourism. Cya nide, a highly toxic chemical, is used to
extract the gold. The daily requirement of cyanide is 24 tonnes just
at the Pueblo Viejo site. Cyanide gets into the hydrological cycle
and poisons aqua tic ecosystems and perhaps even huma n wa ter
supplies.
Factors affecting the location of industry
Human/Economic
• Labour - factories often need to employ la rge numbers of workers
and for this reason it is an advantage to be loca ted in a town or
city. Some industries require highly skilled university-educated
workers. In the UK, several industries of this type are found in the
university cities of Oxford and Cambridge.
• Markets - industries need markets for their products. Someti mes
a market can be another industry (e.g. components for the car
industry) or just t he general public (e.g. clothes and processed
food) .
• Transport - good transport links are essential for many industries
to bring in raw materials and take away finished products. !'or this
reason many industries are close to main roads, railway terminals or
ports.
• Capital - industries rely upon investment in buildings, equipment
and training . This may come from governments or wealthy
individuals and can affect location.
Polit ical
Government policies - governments often encourage industrial
location in certain areas by providing grants or tax-free incentives.
In the UK, this has happened in older industrial areas such as South
Wales where heavy industries have closed down causing widespread
unemployment. The government of the Dominican Republic has
established free-trade zones to encourage new industries to loca te
there.
Physical
• Raw materials - heavy and bulky raw ma terials,
such as suga r, coal and ba uxite, are expens·ve to
transport.
• Energy - in the past, industries were very tied to
power sources, such as coal and •Nater. Today, most
industries use electricity, which is available almost
anywhere at the flick of a switch, so this factor is
less important than it used to be.
• Relief - industries often need ex1ensive areas of flat
land for building and storage (see Figure 2 .11.7).
• Environmental quality - increasingly, industries
are choosmg si tes that are attractive and provide
pleasant vvorking conditions for their employees.
Primary sector case
study: fishing
Fishing in the Caribbean
LEARNING OUTCOMES
Fish are abundant in the warm VJaters of the Ca ribbean and have
always been an important source of food (see Figure 2 .1 2.1). All
countries in the Caribbean have developed small-scale fishing
industries and freshly caught fish, such as flying fish and rnahi-ma hi,
are popular in restaurants.
• Understand fishing methods
used in the Caribbean.
• Understand the ifl"portance
of fishing In the Caribbean.
• Understand the trends and
cha lenges associated with
fish ng.
Fishing occurs throughout the year in the Caribbean. Over 10,000
workers are employed in Guyana and several 1housand are employed
in Barbados and Trinidad and Tobago.
Fishing methods in the Caribbean
CUBA
•
Fishing in the Caribbean mostly involves the use of small boats and
nets to ca tch fish close to the shore .
Seining
Seining involves a net that is kept vertical in the water by corks
floating on the surface. Two boats draw the net together encircling a
school of fish. The net is then dragged onto the boats or to the shore
and the trapped fish are removed. Seining is used to catch king fish,
shark and carite.
a0NITO
Trawling
1
-
O(SIJl'IOU.O INOUSllNA PUOUL•.-
Figure 2. 12.1 Ccban s,amp Illustrating
the iishiog indt.:stry - a
bon to is a sma l tuna,
rather l·ke a mackerel
-12:
Cone-shaped net
dragged along
behind the ship
l
Sea bed
Flsh trapped in the narrow
end of the net
Figure 2.1 2.2 Trawling in the Caribbean
In some countries, such as Trinidad and Tobago and Barbados, fishing
has become more commercialised wi th the introduction of fleets
of trawlers. Guyana now has over 250 shrimp trawlers. Trawling
involves a cone-shaped net being dragged throug h the \'\later by a
large boat (trawler). Fish become trapped in the narrow end as the
net is dra,,vn up to the boat (see Figure 2.12.2). Trawling is often
used lo catch fish that live near to the sea floor. The main fish caught
by trawling are shrimp, carite, snapper and cavali.
Other methods of fishing involve the use of fish pots, to catch
red snappers and jacks, and long lines with up to 1,000 hooks
tha t are towed behind boats to catch tuna, swordfish, grouper
and shark.
Why is fi shing important in the Caribbean?
There are several reasons why the Caribbean has developed a fishing
industry:
• The shallow coastal waters around Trinidad and Tobago and
Guyana are rich in nutrients washed into the sea by rivers such as
the Orinoco m Venezuela and Essequ ibo m Guyana.
• Abu ndant marine life provide food for fish in the coral reefs.
• Mangrove swamps provide important ha bitats and breed ing
grounds for fish and shrimps.
• Many islands have good natural harbours for fishing boats and
ports for export.
• There is a long tradition of fishing for food and trade.
• Tourism provides an important market for fresh fish in restaurants
and hotels, as well as sports fishing .
In Jamaica, inland ponds have
been constructed to develop
a freshwater fish·ng industry.
Wh'le IT'Ost prefer the taste of
saltwater fish, these fresh,Nater
fish are cheaper.
How are fish marketed?
A lot of fish are sold locally from the harbourside to 'middlemen ',
who then sell the fish on to retailers or restaurant owners. This
small-scale marketing is common in villages in Ja maica, St Vincent,
Dommica and St Lucia and in major tourist areas.
Wholesale ma rkets have developed in Guyana, where companies
such as the Guyana Food Processors and Georgetown Seafoods and
Trading Compa ny buy from the fishermen.
Once caught, fish are processed to preserve them. This can involve
salting, common in Barbados and Tobago, smoking and filletmg, or
qu ick freezing. In the 1990s and
early 2000s, the Tobago Sea Products
/ CASE STUDY Beliz.e
Fish Processing plant in Shavv Park,
Tobago processed about 200,000 kg
\Nith an extensive 457 km length of coastline rich fn mangrove
of flying fish, snapper, grou per,
swamps and coral reefs, Belize has one of the best fishing
wahoo and king fish annually.
grounds in the Caribbean. Over 1,670 people are employed in
l
Future challenges for the
fishing industry
A number of challenges face t he
Caribbean fishing industry:
• Over-fishing, often involving
catching and killing young fish
which cannot then mature and
breed. This reduces fish stocks
and is unsustainable. Some widely
available species are under-used at
present.
• Pollution in both rivers and the
sea from oil, sewage and 'Nas te
can contaminate fish and kill off
fish stocks.
• Destruction of mangrove
swamps for build ing and tourist
developments removes importan t
fish breeding grounds and habitats.
• Lack of investment in
refrigeration and ma rketi ng
restricts the quan tity of fish
that can be sold.
fishing, most belonging to a sma ll number of cooperatives tha t
own the modern fish-processing plants.
The most importan t fish products are lobsters, caught in
wooden traps or by divers in the shallow waters along the coral
reefs. They account for over 50 per cent of the export earnings.
Conch, found on beds of sea grass, is exported to the Far East
and shrimp (caught by Honduran trawlers) are processed and
exported to the USA.
Fish stocks have declined in recent years as a result of over-fishing
and damage done to coral reefs by hu rricanes, such as Hurricane
Keith 1n 2000. Some fishermen have moved into the tourist
industry, taking charter boats out to sea in search of deep-sea
fish. Despite these issues, fishing con tinues to be an important
industry contributing some 5 per cen t to Bel ize's gross domestic
product (GDP).
Strider regu lations have recently been introduced to enable
fishing to be more sustaina ble in the futu re. These include
limiting the number of shrimp t rawlers to a maximum of
eight many one year, the introduction of closed seasons and
enforcement of minimum sizes/weights for fish (e.g. conch shell
length must exceed 18 cm). The government is also t rying to
encourage individuals to make grea ter use of the less popular
under-used species.
Look at the following website for more information:
ftp://ftp.fao.org/FI/OOCUMENT/fcp/en/FI_CP_BZ.pdf
Primary sector case study:
crude oil and natural gas
in Trinidad and Tobago
LEARNING OUTCOMES
• Understand the formation,
discovery and explo°tation of
oil and gas,
• Understand the ifl"portance
of oil and gas to Trinu;lad and
Tobago ,
Mi.lions of years ago, plants
and animals liv ng in t he sea
(mostly plankton) d·ed and
collected on the seabed,
Burled and compressed by
overlying sediments, ,hese
organic deposits became
heated and slowly transformed
nto crude oi• and natcra gas.
Trapped by overlying
' mpermeab•e roe~, the o;I
and gas remained deep
underground without
migratng and being lost to
the surface.
'Black gold' in the Caribbean
Crude oil is one of the world's most valuable na tural resources.
For this reason it is sometimes known as 'black gold'. Trinidad and
Tobago is fortunate in having large reserves of both crude o il and
natural gas, which explains vvhy it is one of the weal thiest coun tries
in the Caribbean.
The extractio n o f crude oil and natu ral gas is a good example of a
primary industry. Once extracted, the oil is used to make gasoline,
diesel and kerosene. The gas is used both as a fuel to generate
electricity and as a raw ma terial in the manufacture o f plastics and
fertilisers, which are secondary industries.
The extractio n and refining of crude oil and natural gas provides
cheap energy supplies in Trinidad and Tobago and supports many
secondary industries. This explains the high percentage of workers
employed in this sector compared with other Caribbea n countries
(see Figure 2.10.2, page 139).
Formation and discovery of crude oil and natural gas
The formation of o 'I and gas occurred ma ny millio ns o f years ago and
involved the stages shown in Figure 2. 1 3. 1.
The first oil well vvas d rilled in 1he south o f Trinidad in 1857. f or
100 yea rs oil exploi tation was restric1ed to the land as it was much
easier to extract oil on land than at sea . Offshore drilling began in
the 1950s as technology improved. Today, the largest operations
are offshore, pa rticularly off the east and west coasts of Trinid ad .
Many o f the onshore oil fields are becoming depleted, wit h oil being
expensive to extract.
Extraction of crude oil and natural gas
Look at Figure 2.13.2. 11 sho,Ns the location of the oil and gas fields
m Trinidad and Tobago. Notice the following featu res:
The resu t was the crea,ion
of huge reservoirs o f oil and
gas trapped underground and
availab•e to be tapped and
exp,oited .
Figure 2. 13. 1I Formaiion of oil and gas
• The o ilfields occur in a discontinuous band rough ly east-west
through sou thern Trinidad. Some of the oilfields are offshore in the
Gulf o f Paria and the Atlantic Ocean.
• All the gasfields are offshore with 1he greatest concentration being
in the Atlantic Ocean to the east o f Trinid ad .
• Some gasfields are found to the north of Trinidad and to the west
of To bago.
• Pipelines are used extensively to transport oil and gas to terminals
on Trinidad.
• Oil tankers o perate
out o f Galeota
Point, Poi nt Fortin
and Pointe-a-Pierre,
transporting oil to
markets such as t he
USA.
0
km
so
-
Ol lf~d
Ol ~p!llne
G.as neie<
Gas plf~l~e
._.. far <erle,,,rJnal
♦ 01relfnel)'
• There is a major oil
refinery at Poin te-aPierre where the oil
can be processed.
Importance of
crude oil and
natural gas
The oil and gas
industry is extremely
importan t to the
economy of Trinidad
and Tobago. It brings
in over 70 per cent of
foreig n exchange and
Figure 2.13 .2 Oil and gas resee:es n Tnn'dad and Tobago
accounts for 23 per
cent o f gross domestic
product (GDP) there. It has fuelled massive growth in the country' s
economy and has given many a good standard o f living .
There are several other benefits:
• Over 20,000 persons are d irectly employed by the oil and gas
industry and ma ny thousands are employed in related industries.
• Using oil and gas profits, Trin idad and Tobago has invested money
in other industries, such as a large steelworks.
• There is an extens ve network o f gas pipelines providing a rel iable
supply of energy throughout the country.
• Money has been invested in services (e.g. educatio n, health) and
infrastructure.
• The service sector has grown (e.g. retailing) and this provides yet
more jobs.
Where does Trin idad and Tobago sell its oil?
Most Caribbean oil is transported the short d istance to North
America. Transport costs are therefore relatively low. Americans p refer
to trade wi th stable governments in the Caribbean rather than with
those with polit ical problems in the M iddle East.
Challenges for the future
Oil and gas are examples of non -renewable resources. They are not
being formed today and, therefore, they are fi nite. W hile Trinidad and
Tobago has reserves to last until at least 2050, eventually exploita tion
will be too expensive. Alternative activities \,viii need to be developed
to maintain economic growth .
Several international trans•
national companies (TNCs) are
invo ved n the extraction of oil
and gas in Trinidad and Tobago,
including BP (British Petro eum)
and BG (British Gas). The stateowned Petroleum Company of
Trinidad and Tobago (Petrotrin)
is involved In both extraction
and the o peration of the oil
refinery at Pomte-a-Pierre.
Secondary sector case
study: food processing in
the Caribbean (CARICOM)
LEARNING OUTCOMES
• Understand the types and
location of food-processing
factories in CAR,COM
countries.
• Understand the advantages
and chal enges of foodprocessing industres n the
Caribbean.
• Compare food-processing
industries in the Caribbean
wi th those in Singapore
•• •
Grenada has an international
reputaf on for manufacturing
a liqueu r made from nu tmeg .
De la Grenade Industries
started producing the liqueur
as a small cottage industry in
1996. follow·ng the success
of the product it has recen tly
constructed a modern factory to
mass produce the popular drink.
CARICOM, the Caribbean Community Market, is an organisation
of 15 nations established in 1973. Its ma,n aim is economic
cooperation. These are the members:
• Antigua and Barbuda • Grenada
• Baha mas
• Guyana
• Barbados
• Haiti
• Belize
• Jamaica
• Dominica
• Montserrat
• St Ki tts and Nevis
• St Lucia
• St Vincent and the Grenadines
• Surina me
• Trinidad and Tobago
Types of food processing
Food processing is an important manu facturing industry m the
Caribbean. Food is processed to preserve it and to add value before
it is sold. A huge range of agricultural products is processed in the
Caribbean, including sugar cane, cocoa, citrus fruit, fish, meat, nuts
(such as cashews and peanuts), milk, coffee, vegetables and preserves
of local fruits. Processing involves canning, drying and smoking.
The industry employs several thousand workers across the region
and contributes significantly to exports . Some large multinational
companies such as Nestle are involved, but 80 per cent of the
companies are cottage industries or fa mily businesses. 1\/lany are
owned and run by women . These businesses are generally growing.
Location of food-processing factories
There are 1\"JO main types of location:
1 In food•producing areas, such as where sugar cane, cocoa and
cattle are farmed . This is because 1he raw materials are bu lky and
expensive to transport. They may also be perisha ble and need
rapid processing once harvested.
2 In coastal sea ports/towns where there is a nearby workforce, a
la rge local market and opportu nities for exporting the finished
products. rv'mst food-processing pla nts in the Caribbean import the
ingredients in bulk, and package and process them near the port.
Examples of food-processing locations in the
Caribbean
Jamaica
Look at Figure 2 .14. 1. Notice that the sugar-cane processing factones
are located 1n the main sugar-producing areas and that the rum
factories, \'Vhich use processed molasses, are located nea rby. They are
usua lly extensions of the sugar mills and are
owned and opera ted as an end stage in the
process. Other food-processing factories,
including a flour mill, are concentrated
m the Kingston area benefiting from the
urban workforce, a large local market and
export opportunities. The flour mill processes
imported flou r, which expla ins its port
location.
Se•
Guyana
In Guyana, food processing is concentrated at
the coast (see Figure 2.14.2) for the following
reasons:
f
Clll/bb..n
Sug.ar car.t
• Sugar facto1y
• Rum dlstlllln;
• Foo!I process!r,g factory
F Flou1 mlll
Figure 2, 14. 1 Locat<on of food processing 1n Jamaica
• Nearby food-producing areas (sugar cane,
cattle, vegetables).
• Close to fishing grounds that provide fish for
processing .
• The ca pital Georgeto\<Vn and other coastal towns
provide a workforce and a large domestic market.
• Ports ena ble processed products to be exported.
In the sou th of Guyana there is a large modern meatprocessmg factory at Lethem, located \<V1thin a major
ranching region. Here, beef is processed for sale in
Guyana and nearby Brazil. There are plans to develop
an organic beef industry in the area. In addition to beef,
there is a cashew nut processing factory.
Guyana can already feed itself and has a seven-year plan
to increase production to process and export.
Advant~ges of the Caribbean for food
processing
"
+
VENEZUELA \.,Anna; egln ' Georgetown
{°~···· 'I: Bartica .-
<· . . *
i Linden •
*
Mt.···• . _ .•
Roralw, :
WesternGuyana
Meat (beeQ
processl09
aid cashew ni.'1
processlll'J
,i:
i
Coaslal 1one
Sugar faciotles and
I00<1 p,ocesslr9 of
local crops,
benefl1lno fto.m
plenllul laboll!,
local matkets and
i
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.,.
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SURINAME
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Figure 2. 14.2 Location 0$ food process ng 1n Guyana
These industries continue to be importan t and growing.
Below are some of the reasons why:
• Ra~v materials are mostly from local farm·ng and fishing, so they
do not have to travel far from source to processing si1e and then
to market. This cuts production cos1s.
• Etticien1 transport net,Norks (road and port) already exist.
• There is a readily ava ilable supp!y of experienced workers.
• Ne,N technologies for storing food products are used whenever
poss•ble.
• Some Caribbean countries place high import taxes on imported
food products to make home-produced goods more competitive.
Challenges for food processing in the Caribbean
While food processing remains a gro,Nth industry in many CARICOM
countries, there are potential problems. Many raw materials come
..
from small -scale producers w ith gardens, o rchards or fishi ng boa ts.
These suppliers are not always consisten1 in their production, l"mi ting
the capacity of the food-processing factories. Pressure to build houses
in Belize has reduced the area o f orange o rchards, reducing juice
manu fac1uring capacity in Trinidad and Tobago. Hurricanes may also
reduce agricultural production.
Some fruit crops have suffered as a consequence of disease, for instance:
• the citrus 1risteza virus reduces citrus harvests in Trinidad and Tobago
• the pink hibiscus mealybug has attacked pineapples in Dominica
and Guyana.
Since 1he maj ority of companies invo'ved are very small, staff training
and research and development are no t prioritised. Competition
from larger companies, such as those in the USA, threatens fu ture
Caribbean success.
Th e f uture of food processing in CARICOM countries
Despite d ifficulties discussed above, many CARICOM countries
are planning to develop their food processing industries further.
,. , ! ,
,.
Expanding populations, within some Caribbean
countries and in those to whom 1he food products
are sold, mean more food is needed . Using as much
as possible o f w hat the Caribbean produces itself cuts
import costs. f or example, food processing can u tilise
frui t not quite good enough for exporting, and that is
consumed \'Vi thin the Caribbean . Some food -processing
businesses are based on imported foodstuffs, such
as New Zealand d ried milk \'Vhich is converted in the
Caribbean into condensed milk for 1ypical local recipes.
With governments backing food processing there is the
potential to grO\'V further; food processing is likely to
remain an important part o f the secondary economy of
the CARICOM countries.
'-'--"-'---'--''---C..>
Processed sauces produced in 1he Caribbean
A secondary sector comparison : food processing in
Singapore
Development of large-scale food-processing industries in
Singapore
Over 42 million people live in the Ca ribbean, and 5.3 millio n live in
Singapore, only sligh tly more tha n in St Lucia . The food-processing
industry in Singa pore, with over 800 fac1ories earni ng over US$4
billion in 201 1, is much larger than that in the CARICOM countries.
As o ne o f t he earliest manu factunng industries in Singapore,
food processing is today one of its largest. It began as small-scale
businesses, based o n local cul tu re and traditions, and there are still
t
such businesses thriving . Overall, therefore, there are clear simila rities
and differences with the Car,bbean pattern.
Singa porean food manufacturing industries went through periods of
severe difficulty caused by regio nal and global political and econom ic
issues, including :
• the economic recessions of 1986 and 2008
• the Asian financial crisis (1997)
• the bird flu epidemic (2003).
Nevertheless, food processing remains the seventh largest
manufacturing industry in terms of income generated.
Belo,N are the sim ilarities and differences between the Singaporean
and CARICOM food-processing industries.
How are Singapore and CARICOM countries similar?
• The majority of businesses (95 per cent in Si ngapore) are classed
as small and medium-sized enterprises (SM Es) vvith up to 200
employees; the remaining very la rge o nes tend to be multinationals.
• Export markets are important as a sou rce of GNP (see 'Did you
know?').
• Efficient road and port nel\,vorks o pera te to make distribu tion and
export effective.
How is Singapore different from CARICOM countries?
• Businesses are most commonly located on industrial estates.
• Most raw ma terials are imported as Singapore has limited amounts
of agricultural land .
• La bour supplies in Singapore include migrant workers as well as
local people; a total o f 19,000 people are involved compared with
13,000 in CARICOM countries.
• H,gh-tech equipment dominates, and research and development is
very importan t.
• Government involvement in Singapore is g reater - suitable
buildings are provided; products are duty free; taxes are kept low.
Challenges fo r the future
Salaries in Singapore are relatively hig h compared with the rest o f
Asia, meaning foreig n competition can sell at lower prices, and, since
Singa pore's population is only 5.3 million people, that lim its the
local market. Global prices for raw materials tend to rise. In order to
be more in con trol of their costs, some Singaporean companies are
buying land in China to g row their own ra,N materials on huge farms.
Consumers are increasingly aware of what they are eating from
the health and nutrition poi nt of view. Eating too much processed
food does not form a ~vell-balanced diet. Positive images and good
advertising are important.
Singa pore is a global cen tre of finance and investment and therefore
has the financial backing and flexibility to meet future challenges.
Singapore's food-processing
industry has an int ernational
profile, ·n the rest of Asia
and beyond. Its exports go
all over the world: to Japan,
China, Malaysia, Indonesia,
Thailand, Taiwan, Vietnam,
Hong Kong and the USA.
Tertiary sector case study:
tourism in the Caribbean
LEARNING OUTCOMES
• Understand the irr portance
of tou r sm in the Caribbean.
• Understand vvhy tou r sts
choose to visit the Car bbea n
and recent trends.
• Understand that tourism
brings both advantages and
disadvantages.
Tourism is travel for pleasure. More than 100 years ago, only the very
wealthy could afford it, but it has now become increasingly common
for people to have holidays. During the 20 th century Europeans and
Americans began to visit the Caribbean islands, mainly choosing t heir
previous colonies:
• The British visited Jamaica and Barbados.
• The French liked Martinique.
• The Dutch preferred Cura~ao.
• The Americans often chose Cu ba and the Baha mas.
The importance of tourism
Tourism is an example of a tertiary industry because it provides
serv,ces for 1ourists in resorts, hotels and restau rants. Tourism
also supports secondary industries, particula rly those involved in
the production of crafts, furnishings and processed foods. It also
supports pnmary industries such as farming and fishing.
In the Caribbean, it is for most coun tries the fastest-growing and
most importa nt industry, providing much-needed foreig n income and
supporting thousands of jobs (see Figure 2.15.1).
• In 2014, almost 26.3 million tourists visited the Caribbean, up from
18.5 million in 2005. This could rise to 28 million by 2021.
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Figure 2.15.1 The mportance of tourism in the Caribbean
•
~
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i I :i.§ cili
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• In 2014, 14.6 per cent of the Caribbean's gross domestic
product (GDP) came directly or indirectly from tou rism.
This is t he highest con tribution of any region m t he 1,vorld
and shows how dependent the Caribbea n is on tourism.
• In 2014 some 2,231,500 jobs 1,vere directly or indirectly
supported by tourism in the Caribbean, equivalent to
13 per cent of t he 1,vorkforce. By 2025 this is expected to
rise to 2,788,000 (14. 4 per cent of the workforce) .
What are the attractions of the Caribbean?
The Caribbean has much to offer tourists as Figure 2.15.2
illustra tes. Attractions include the following:
• The area has a 1,varm year-round cl ima te, particularly
popular during t he winter (December-March) when
conditions are cold and dark in the USA and much of
Europe.
• There are spectacular landscapes, 1,vith beau tiful beaches,
warm seas, forested mountains and volcanoes.
• The Ca ribbean has a rich cu ltural heritage and direct connections
wi th many European (former colonial) countries.
• The area is mostly free from the insect-borne diseases associated
wi th exotic locations elsewhere in the vvorld .
• English is 1,videly spoken and locals are friend ly, relaxed and
welcoming.
• 'The paradise' image is portrayed by books and films, such as Pirates
of the Caribbean .
Why has tourism grown rapidly in recent years?
Tourists first started to arrive in the Caribbean during the 18th century.
They 1,vere mostly wealthy Europea ns taking pa rt in 1,vhat became
known as the 'Grand Tour'.
Mass tourism, involving thousa nds of ordinary individuals, took off
from the 1960s and has increased rapidly since the 1990s. There are
several reasons for this rapid growth in tourism:
• Greater availability of relatively cheap fl ights and cruises from
Europe and the USA.
• Increased incomes w,th more money available for travel and
holidays.
• Increased available leisure time, with paid holidays now
commonplace.
• People living longer, healthier lives and often wishing to travel the
world after retirement.
• Increased awareness of opportu nities for tourism in far-off places
through advertising, television and, most recently, the internet.
As more and more tourists have flocked to the Caribbea n, there has
been a massive increase in the provision of resorts, hotels, bars and
ca fes. Si tes for tourism, such as plan tation houses, natural wonders
such as Harrison's Cave in Barbados, and beach resorts have all been
developed in recent years.
Trends in tourism
Look at f igure 2.15.3. It describes some trends in tourism in the
Caribbean. Notice the follov;ing important points :
• The vast majority of tourists (nearly SO per cen1) come from the
USA. This is because the islands are relatively close and ma ny
tourists choose to take their holiday during 1he \'Vinter w hen the
\'Veather in the USA is often cold and gloomy.
• There are large variations in the number of tourists visiting different
countries. Huge numbers (mostly Americans) visit Puerto Rico, the
Dominican Republic, Cuba and the Bahamas.
• European tourists o ften visit ex-colonial countries \'Vhere there is
a common language. So, for example, ma ny British tourists visi t
Tourist arrivals by country of origin, 2009
0
USA
O France
0 Caribbean
O Canada
O UK
0
0
0
Spain
Q
lialy
Germany
Sou1Jl Arrerlca
[I Swltterland
0
Rest of Ill< Wortd
Tourist arrivals in Caribbean countries, 2009
I
Jamaica
I
I
I
I
I
I
I
Puerto Rico
I
I
I
I
Dominican Republic
j
I
I
Guadeloupe
Trinidaoan<! Tobago
D
I
Bahamas
I
I
Cuba
I
Barbados
0
500.000 1.000,000 1.500,000 2,000,000 2,500.000 3.000.000 3.500,000 4.000,000
Total number
Flgure 2.15.3 Tour sm trends In the <:aribbean
Jamaica and Barbados whereas t he French are more likely to visil
countries such as Martinique.
• While mass tourism ,s popular in counlries such as Puerto Rico,
expenditure per 1ouris1 is highest ,n lhe smaller, more exclusive
islands such as lhe US Virgin Islands and the Cayman Islands that
appeal lo very wealthy businessmen and celebrilies.
The advantages and disadvantages of tourism
Tourism brings many obvious advanlages, such as foreign income
and employment opportunities. There are, however, a number of
disadvantages loo. Figure 2.15.4 lists t he main advantages and
disadvantages. Try to relate these general poinls to your home territory.
Advantages of tourism
Disadvantages of tourism
Employment - many persons
Environmental damage - tourisl
are directly employed to serve
tourists as guides, waiters,
cleaners, cooks, etc. Indirectly,
many persons gain employment
too, for example, in construction,
food supply, electrical and
plumbing businesses, and in
making crafts and souvenirs.
developmenls, particularly
at the coast, can damage or
destroy nalural ecosystems,
such as mangrove swamps and
coral reefs. Nalurally attractive
landscapes can become
scarred by poorly designed
developmenls.
Foreign income - tourists spend
Pollution - waste management
their money m US dollars, euros
and British pounds, which
provides an important source
of foreign income. Spending
on goods and services in t he
Caribbean also helps to boost
the economy by providing
tax income.
can be a problem if tourism
develops rapidly, leading lo
contammalion by se,Nage and
untreated waste.
Agriculture and fisheries -
Economic dependency - some
tourists provide a huge market
for food crops, such as fruit,
salads and vegelables, as well
as demand for fresh fish.
counlries can become overdependent on tourism. so 1ha1
any reduction in numbers (e.g.
owmg to global economic
recession or lerrorism) can have
calaslrophic effecls.
Multiplier effect - tourism has
Social issues - occasionally
many useful knock-on effects
on lhe economy such as
improvemen1s in infraslructure
(roads, airports, electrici1y and
water), construction, retailing
and other industnes.
tourism can lead to problems of
drugs, crime and proslilulion.
This can cause social conflicls
between touris1s and locals.
Figure 2.15.41 The advamages and d sadvantages of tounsm
:n the Caribbean
Accord ing to Orb;tz, an online
travel company, the 'best scuba
island' in the Caribbean is Turks
and Ca,cos, the 'best natural
wonders' are on Dominica, the
'best beaches' are on Barbados
and the 'bes! advenlure island'
is JarPaica. Do you agree?
Tourism case studies:
Jamaica and Belize
Jamaica
LEARNING OUTCOMES
• Jama ica is the Caribbean's fi fth most visited country after Puerto
Rico, the Dominican Repu blic, Cu ba and the Bahamas. Almost
2 million tourists visi t the island each yea r.
• 80 per cent of tourists come from the USA and about 10 per cent
from the UK, ma ny arriving on cruise ships.
• Tourism is an important source of foreign income and accounts for
about 20 per cent of GDP.
• Tou nst attractions include
the ex1ensive sandy beaches
Jamalan tourism facts and Rg11ra1
1
l1 al\ t-ourlst areas
Solan.; garden
l il!al ,urnl!er o' IOJ~st a·1,as
' ,322 $90
with wa rm tropical seas,
s outside main t Gc,f ecu,ae
0 Ho;e:
Po111.
ato:,
11m11loyed
1
IOJ~Sm
tourist areas
a U1,:seJm
'Na ter sports, fishing and
111-J~st ~
!l~ure {Iler pe,10'1}
US$9ll
~ Beacl\lba1hlng areas ,r Srd >o1ru~/
l ~allo-al~neic,,,ange ~!ngs
US~l.3 hll o,
golf, wildlife, and historical
Jf. WldHe reStl\'8
~ Waterspons
2')$
Oon:!lh.11 on~ GOP
and cul tural sites, such as
• Oe,p-s,a fishing D t1atl(l('I& P~
CrJs.e, snip SIT't'l!S {2002)
8&6
Pa.-lsb 011ur.:lal'(
• ~ an:a~o., house
Rooir..s io'a: ab'e-to ~ur.:S.W (20C'2.)
14)8'
plantation houses, and
-t A~ot
A. Caves
V•sllors. 1ftl1l USA and UK•~of ICU\
70\\and 1~
Jamaica's music.
• Tou nsm directly supports some
220,000 jobs in shops, hotels
and restaurants, and many
thousands in, for example,
construction, food production,
transportation and crafts.
• Jamaica faces competition
from other Caribbean islands.
O km 30
This explains the development
of specialist types of tourism
such as adventure tourism,
Figure 2.1 6.1 Jama1ca tourism: facts and iigures
ecotourism and community
tourism.
Adventure tourism includes ac1ivities such
as cliff diving at Negril, bouldering at Dunn's
River Falls and ziplining in Montego Bay. A
number of companies offer holidays involv·ng
People visiting Jamaica 1920-2013
these activities.
2,000 ~ - - - - - - - - - - - - - - -/~
• Understand the charactefistics
of toursm in Jamaica and
Beize
• Understand the pnncip'es of
ecotourism.
·~
*
:jg'
~
8
:€.
j
·~
1,800 .,__ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _....,.
1
1,600 +-----------------1-,'--t
1.400
1,200 -t------------=..<::..-----i
1,000 - t - - - - - - - - - -7"""'=-------l
800 +----------+✓-------;
600 - t - - - - - - ----,:::,-'/" ----------l
400
+----------------_,,.,-r--i
+------=-- "'---------------!
t:;;~=;::::'./~==========j
20~
1920 1930 1940 19'50 1960 1970 1980 1990 2000
Yeai
F1gure 2.16.21 Jamaica. trends in visitors
2013
Ecotourism involves small specialist trips
focusing on nature. Jamaica has abundant
bird life and natural vvonders. Tours include
wildlife watching in the Blue Mounta ins and
bamboo ra ft trips to explore the rainforest
along the Rio Grande.
Community tourism consists of tourists being
provided with overnight accommodat'on in
local people's homes. This enables them to get
to know local communities and experience the
Jamaican way of life.
Belize
What is ecotourism?
• Ecotourism involves small special groups experiencing and
learning about the na tural 'Norld.
• Ecotourism conserves the environment, making use of local
building ma terials and avoiding enviro nmen tal damage and
pollution.
A phrase often used to describe
the philosophy of ecotourism
is 'leave o nly footprints and
take only memories'. Why do
you think this is an appropria te
phrase 7
• Local people are em ployed as guides, resources such as \'\later and
energy are conserved, waste is recycled and tours usually involve
walking or rafting.
• Ecotourism is an example of sustainable development in that
communities benefit wi thout suffering environmental damage. It is
a long-lasting form of tou rism.
Ecotourism in Belize
• Belize boasts a large number of national parks and natural reserves
which, together with its extensive coral reefs, \<Vild stretches of
coastline and tropical rainforest, make it an ideal location for
ecotourism.
• Many hotels and lodges make use o f rainwater for washing and
showers, use renewable supplies o f energy to genera te electricity
and make use of local building materials in construction .
• Tou r guides and adventure providers are well trained to pass on
informatio n to tourists about environmental conservation, for
example ways of protecting rather than damaging coral reefs.
• People are encouraged to be sen9'tive to local tradi tions, not
to purchase artefacts or natural souvenirs such as shells, not to
approach wildlife, and to dispose of \<Vaste in designated containers.
• Among the most popular attractions for ecotourists are the Maya
terrples and ruins, coral reefs and beaches, hiking or biking the many
jungle trails, visiting the Belize Jaguar Preserve, kayaking o n the rivers
and streams and visiting the many underground caves and caverns.
CASE STUDY
Black Rock Lodge. Belize
Black Rock Lodge is nestled in dense rainforest overlooking the
Macal River in the foothills o f the Maya Moun tains just twoand-a-half hours west of Belize City. There are opportu nit ies for
canoeing down the M acal River, horseback riding to the f lour
Camp Caves o r hiking u p the var"ous canyon trails to spot the
w ild birds and animals.
Electricity is supplied by a customised hybrid system involving a
micro-hydro scheme and solar power. All water is supplied from
a local spring and is conserved and reused \<Vhere possible. Locals
act as guides and work at the lodge, and much o f the food is
produced locally and is o rganic. Waste is recycled or composted
and waste water passes throug h a \<Vetland system \<Vhere 1t ·s
filtered and cleaned.
f
s2
Figure 2.16.4 A Belize stamp sho\Oi ng
the importance of wildlife
Quaternary sector case
study: ICT industries and
call centres
As early as 2007, Caribbean
countries were reporting a
significant increase in use of
their offshore service industnes
by 'arge American corpo rations,
including commu nications giant
AOL. The corporation chose
St Lu6a as its call centre location
in preference to India because o f
the lov,er communication costs
and the fact that loc,;11vvorkers
relate vvell on the telephone
to the American market. The
general hospi1a ity of the region
was a further attraction to AOL.
US$2.5 bill o n comes into the
region from sel'V'ce industries.
The quaternary sector is the part of the economy w hich deals
with providing information and expertise. A quaternary business
serves other busi nesses. Examples include customer relations, call
centres, training, resea rch and development. Knovvn as footloose
industries, they do not rely on the locations of raw materials or
markets. Communication is primarily by phone, the internet and
satellite, w hich are available almost everywhere. The key location
factor is a suitable workforce.
ICT industries in the Caribbean
ICT industries are an important route to economic development in
any country in the world . Most Caribbean countries are now wellprovided for in terms of telecommunicatio ns, especially landline and
mobile phone systems. Nevertheless, infrastructure distribution is
u neven and expensive to construct.
Jamaica
Ja maica now has 15 cable TV channels and there has been
considera ble growth in 'new media'. Tradi tional radio and TV
cha nnels are now supplemented by niche and community-based
radio sta tions as well as independent televisio n providers. However,
the change from traditio nal to nevi media systems that is happening
globally remains slower than average in the Caribbean because of low
levels of growth in internet and fast broadband services.
Nevertheless, the Jamaican government recognizes ICT as a tool for
economic g rovvth. A commitment to !CT education in schools ensures
skills for the next genera tion . A t the same time, local businesses can
be slO\'V to adop t new technologies due to current lack of skills o r
finance, which does limi t growth.
Haiti - a special case
Even Haiti \'Vith its history of regular hurricane and earthquake events
likely to d isrupt such commu nications, has reasonable landline,
mobile and internet services in urban areas. In contrast. rural areas
often lack phone lines, internet and even simple electricity lines.
There is po tential for improvemen t in these systems, but one can
u nderstand tha t major companies are unwilli ng to invest in high-nsk
areas, limiting regeneration .
Telecommunications in the Caribbean
The ICT industry of Costa Rica
Costa Rica \'Vas previously dependant o n agriculture and then on ecotounsm, but has recently developed a modern ICT industry, ahead
of other Caribbean coun tries. Intel, the gian t microchip processor
company, loca ted a base there in 1 998. Other
related industries were therefore attracted to
Costa Rica and adjacent Caribbean countries.
Costa Rica is involved in the manufacturing
of both integra ted circuits and related
electronics, w hich is essentially secondary
industry. The quaternary aspect here is research
and development into new systems for
manufacturing and export, boosting the Costa
Rican economy. The share of ICT busi nesses in
Costa Rica n exports grew from $1, 100 million in
2008 to 2,100 million in 2012 , from 11 per cent
to 22 per cent of GDP (Source PROSIC 2013) .
Costa Rica's government has a policy of
Figure 2 .1 7 .1 ICT education n a school
supporting ICT companies and o f using these
skills to provide ICT equipmen t (computer
labs) and skills educa tion in schools (see Figure
2.17.1). ICT companies pay taxes to the Costa Rican government,
w hich funds educat·o nal development, as well as being an
investment in computer systems supporting secondary and tertia ry
industries, plus operating government systems. Overall, ICT industries,
including quaternary research and development, have a positive
impact on the country's economy.
Call centres in the Carib bean
The Caribbean is increasingly at1ractive to q uaternary sector
businesses and to call centres in particular. The region ca n provide
plenty of well-educated workers a t relatively lo\,v pay levels.
Call centres in the UK and USA have often closed down due to
competition from countries such as India and Indonesia where
the o rganisa tio ns were more cost effective d ue to lower wages.
Caribbean and Indian hourly wages are around USS 16.50, compared
w ith US$29 in the USA. British and American compa nies therefore
moved their call centres to Asia.
However, some users o f Asian centres found difficul ty understanding
the spoken English of the call hand lers. English is the first language
in many Caribbean countries, g iving them a clear advantage in this
market. Some Caribbean governments are offering tax and o ther
incentives to a ttract new, long-term contract clients.
Ma in call centre cou nt ries in the Caribbean include Jamaica,
Barbados, Trinidad, the Dominican Republic and Puerto Rico (see
Figure 2. 17.2). These last t,No can o ffer services in Spanish as well
as in English. In 2015, 4 1 million Americans ( 13 per cent of the
populatio n) used Spanish as their first or only la nguage.
This all sounds very positive but there are inevitably some
d rawbacks. Set-up costs are h•gh d ue to the expense of bringing
in high-tech equipment. From time to time cultural differences
have led to some di fficulties . Nevertheless, growth in Cari bbean
call centres has been rap'd. The number g rew from 44 call centres
across the whole Caribbea n in 2001, with 11,000 \,vorkers, to over
55,000 by 2008.
-...:
-.....r~
Figur e 2.17 .2 A Caribbean call centre
worker
Agriculture in the
Caribbean
LEARNING OUTCOMES
History and development of agriculture in the
Caribbean
• Understand the characteristics
of Small-scale farming and
commercial plantations.
Agriculture involves growing crops and raising livestock on the land.
It is an example o f a primary industry.
• Understand the irrportance
of agricu lture
• Understand the patterns and
trends n agriculture,
· 1 t 111-1. I ] I • '."41 ,1 1 t
111• r .-
Historically, the co1on'al
p laniation system dominated
agriculture, and indeed
the w hole economy of the
Caribbean. Onginally, the labour
force cons•sted of slaves. The
system existed to export raw
materials to Europe. Today's
sugar plantations are large-scale,
modern opera1 ons (see the case
study, page 173). Smaller-scale
farms a so produce sugar cane.
In the Caribbean a dual agriculture economy has developed .
1 Small-scale family-owned farms, w here a variety of cro ps are
grown and livestock is reared (see Figure 2.18.1 ). The produce is
used by the household as ,,veil as being sold locally at markets and
to supermarkets. This is a traditional type of agricu lture,
2 Commercial plantations were develo ped during the colonial
era alongside the smaller traditional farms. These plantations
concentrated o n grov.,ing a single crop such as sugar cane,
ma king use of la rge numbers of workers to maximise production
and profit. Many plantations still exist today, concentrating on
producing food products for export (see Figure 2.18.2).
The importance of agriculture in the Caribbean
• Agriculture con tributes to gross domestic product (GDP) and to
export earnings. Several countries' economies are very relia nt
on ag riculture, for example Haiti (24 per cent of GDP), Guyana
(21 per cent) and Dominica (16 per cen t). Generally, the trend in
the Caribbean is for this to fall as the service sector grows.
• Thousands of individuals are employed in agriculture. In
Hai ti 38 per cent of the workforce is employed ir1 agriculture.
Figure 2.18.1
• I
Sma1 1..scate uad1tiona! farm in the Caribbean
Figure 2, 18.2 Caribbean banana p antation
Elsewhere, Dominica (40 per cent). Guyana (30 per cent) and
St Lucia (22 per cent) are also heavily dependent o n agriculture for
providing jobs. The widespread increase in the use of machines
and chemicals means that the number of individuals employed is
declining.
• Farming provides a grea t deal of food for locals, reducing the need
to rely upon expensive food imports.
• Agriculture provides raw materials for secondary industries such as
food processing and the manufactu re of rum.
KEY TERMS
• Incomes generated by farming supports local services such as shops
and ca fes.
Arable: where la nd is ploughed
and used for g rowing crops.
Pastoral: where livestock are
grazed on grassland.
•
Subsistence agriculture:
grow ng crops and raising
hvestock to feed the fam .ly only
Corimerc al agriculture:
grow ng crops or ra,s•ng
l'vestock to sell and make
money.
Int ens ve agr cu ture:
producing a hig h yie d per
hec1are, of1en involving the
use of chernica Is and expensive
machinery or labour.
Figure 2.18.3 Caribbean market
Extensive agriculture:
producing a low yield per
hectare, of1en on low-qual ty
land or \'\11th little nvestrient.
Agricultural land use in the Caribbean
Despi te falls in production, both
commercial and subs1s1ence
systems of agricu ture remain
important in the Can·bbean as
sources of:
Look at f igure 2.18.4 \,vhich shows land use in the Caribbean.
• local foodstuffs
• family income
• fore gn exchange.
• Cuba has the largest land area in the Caribbean and over 50 per
ce11t of all the Caribbean's farmland. This helps to expla in the high
rate of agricultural employment in Cuba. More land has been
brought into production in Cuba (50 per cent in 1975, increasing
to over 61 per cent by 2011 ).
N
t
Notice that the pie charts have been drawn in proportion to the
total land area of each country. Cuba has the largest land area and
the biggest pie cha rt, follo\,ved by the Dominica n Republic and Haiti.
Each pie chart has been split into the relative la nd uses.
=)
Bahamas
1,394,000
0
~ ) ~11.
'S>.
km
500
Atlantic Ocean
..,. ...________
P
Dominican
a1 Republic
4,873,000
Cayman Is.
-_,..__ 25,900 •
Puerto Rico
890,000
\
Virgin Is.
(US)
Virgin Is.
(UK)
34,000
15,300
J
L·/
.,..,....,J (jc:;;.., ,.
Anguilla
g 600
'
•.
St Kitts and Nevis
~o
36,000 ,y----
Caribbean
Sea
Jamaica
1,099,000
(i
Antigua and
Barbuda
44,200
(])-.
~
Guadeloupe
17~
~
Montserrat - _.,... :'.. _,,,..,..... Martlnique
Nethenands 10,200
lol°°
110,000
Dominica Q.--- - -~
~ 75~
(),,._
St Lucia
St Vincent and
·
~ 61,000
theGrenadines
O Barbados
800
C....--"l:•
43,000
Tnnldad and
Grenada
l,....i.:::;.,J Tobago
~ ~?J. .
Hpiti
2,775,Q(IO
Land use
Arable land
Permanent crops
C>
C>
C> Permanent pasture
► Forest and woodland
C> Non-productive
Flgure 2, 18.4 Agricultural land use n the Caribbean
/
0
34,000
513,000
• Cuba, the Dominican Republic and Haiti account for 90 per cent of
the region's farming area .
• Agricultural land occupies 44 per cent of Barbados and Jamaica.
This is declining owing to urban and tourist-related developments.
• There is great contrast across the region . For example, the Bahamas
has a high proportio n of forest and woodland as does Dominica,
Trinidad and Tobago and Guadeloupe. Barbados has a high
proportion of arable land w hereas the Dominican Republic has a
high pro por1ion of permanent pasture. This variety is largely the
result of physical geography (relief, rock type) and historical factors.
Recent trends in Caribbean agriculture
• The agriculture workforce declined from 50 per cent in 1960 to
20 per cent in 20 10. This is largely the result of increased use of
machines, together with the growth of employment opportunities
in the service sector.
• Increased productivity led lo an increase in exports in the 1970s
and 1980s (more than 6 million tonnes in 1986). However, since
the 1990s, exports have fallen, reducing to as low as 2 million
tonnes in 200 1. This can be linked to an increase in service
industries and a \'Vider range o f jobs available. Reasons for the
decline were, among other things, a ruling of the INorld Trade
Organization that removed the protected market arrangements for
former colo nies, as \'Veil as hurricane damage.
• Fertiliser use increased between the 1960s and 1980s but later
reduced w hen it was proved that its over-use can be a problem .
• There has been a gradual loss of protected markets for sugar,
bananas and other crops because of competition from low-cost
producers in South and Central America .
• The development o f o rganic farming and f air Trade bananas has
helped the Ca ribbean to provide for a hig h-priced niche market
in Euro pe, and some farms have remained in business. The
maJor Caribbean Fair Trade ba nana producers are Dominica, the
Dominican Republic and Grenada.
• Other plantations have diversified their productio n, including
gro\,ving flo\,vers and providing vegetables for the local markets.
• In Guyana, the rice farmers have developed specialised rice varieties
to improve yields. They have also targeted their sales by developing
parboiled rice products to sell this hig her-priced commodity to
more Caribbean countries.
In Barbados, the amount
of productive farmland has
decreased ·n recen t years,
especially alo ng the west coast.
This •s because farmers have
sold land for hous ng and tourist
developmen ls, especia ly allinc usive resorts. Some farmland
is left unused while wa1i n~ for
developers to make a sufficiently
high bid to purchase the land.
Characteristics of
commercial farming
in Jamaica
LEARNING OUTCOME
• Understand the characteristics
of comlT'ercia farming in
Jamaica.
Patterns of land use in Jamaica
less than a third of Jamaica is sui table for farming . There are several
reasons for this:
• About 50 per cent of the country is over 300m high and much of
this land is made of steep slopes (1 :5 or 20 per cent or more). Access
is often difficult and machines cannot be used on steep slopes.
• limestone areas develop thin soils and have little svrface water
(limestone is a permeable rock that allows water to pass through it).
• Some of the slopes have become vulnerable to soil erosion following
widespread deforestation for timber and charcoal production.
'.ii DID YOU KNOW?
n 2005, Jamaica suffered from
a senoJs drought bet\'leen
January and April. La ter in
the year t was struck by tvvo
powerful hurricanes, Dennis
and Emily. These cl imatic events
caused considerable damage
to Jamaica's agricul tural sector.
Some 40 per cent of the coffee
harvest was lost and the banana
industry wacs almost totally
destroyed.
• ·,
...Poortia
w··
'
km
50
Land use
D
Forest
-
D
Swamp
Pasture
-
Sugar cane
-
D
Coconuts
Bananas
Mixed/scattered farming
-
Built-up areas
Figure 2.1 9.1 Jamaican agr'cultur<:11are-as
Look at Figure 2 .1 9. 1. It contains information about farming in
Jamaica. Notice the following:
• The main land use in Jamaica is forest (24 per cent of the total land
area).
• While a variety of commercial crops are grown, sugar cane is by fa r
the most important in terms of land use and production.
• Large concentrations of sugar cane are found close to the coast,
particularly in the south and the west.
• Banana produc1ion is extensive in the rainier north-east, such as
Portland and St Mary.
..
• Small concentrations of coconut plantations are found on the east
and north coasts.
• Traditional small-scale farming is scattered across Jamaica,
particularly \<Vithin areas of scrub and woodland .
Land use
0 Major crops
0 Grassland
D Forest
0
Scrub and woodland with patches of subsistence !arming
0
Unused - potentially productive lor !arming
□ Permanently unproductive
0
Built-up areas
Figure 2.19.2 Jamaican land l.iSe
Land ownership and size of farm
Ja maica functions as a dual agricultural economy. Average farm
size has increased, but inequalities in land ownership created in
colonial times remain. Plantations \<Vere owned by weal thy people for
commercia l export. This situation continues, except that large-scale
family businesses have often been replaced by b'g companies, some
multinational.
This inequality is illustra ted by these facts:
• The largest 1,400 holdings - at least 20 hectares (ha) each - make
up 54 per cen t of Jamaica's farmland .
• 60 per cent of farms are less than 1 ha.
• Another 17 per cent are bet,Neen 1 ha and 2 ha.
Family farms have become less common and corporate business
now has an increasing role in Jamaica 's agricu ltu ral economy. l argescale holdings often have the best land, \<Vhile small farmers remain
on the poorer land . Security of tenancy is also an issue for poorer
fa rmers - some pay rent, although there is always the risk that their
landlord will decide to sell the la nd .
Commercial arable
Small-scale farming
Location
Kew Park f arm, about 10km south of
Mon tpelier
f arms close to Windsor in Cockpit
Country
farm size
385 hectares (ha)
Small, mostly less than 1 ha . Land is very
fragmented. Farmers o ften have to cycle
between plots o f land.
Labour
40 fu ll-time workers and up to 100 parttimers during coffee harvesting. Some
live on site, others travel from nearby
villages. Wages are lov,.
Family labour only. Most farmers are
o lder (60 per cent over 50).
Crop~ ivestock
Mostly commercial beef cattle ranching
(700 animals). Also 16 ha coffee, 2 ha
citrus fruit, 2 ha lychees, over 2,500 pigs
and 2,000 free-range chickens.
Some sugar cane is produced as a cash
cro p, o therwise a variety of arable food
cro ps (e.g. yams, maize, sweet pota toes
and cabbage), tree crops (bread frui t,
avocado and coconuts) and livestock
(goats and cattle) are produced .
Markets
All produce is sold. Coffee is partly
processed o n site then sent to Kingston
to be graded, roasted and packed. Fru it
and eggs are sold locally. Pigs are sold to
loca l processor, Grace f ood Processors.
Sugar ca ne is processed at the Long
Pond factory. Excess food is sold at local
markets.
Figure 2.19.31 A comparison of farming in Jamaica
Labour, capital and technology
KEY TERMS
Monoculture: the product"on
of a single cro p, usual y
w ·t h high inputs o f capital,
mach nery, technology, qual 'ty
seed and fert'llsers. A sing e
cr"Op w, I take the same
nutrients out of the soil every
year, reducing the fert lity of the
soi and somet Mes damaging
its structure. Chemical fertil izers
are used lo feed the crops, but
in large quantities they can sti I
damage the sol
Capi tal inputs into commercial holdings red uce the demand for labour.
Figure 2.19.3 illustrates a large commercial farm vvi th only 40 fulltime workers. This surprisingly low number is the resul t of dependency
on mechanised farm equipment. This means h igh energy use from
unsustainable fossil fuel sources, w hich is expensive and polluting.
Administration and communica tio n wi th customers is largely done
via the internet. La rge-scale commercial agriculture is capital intensive
and technology dependent.
Jamaica's farming practices and products
Monoculture dominates large-scale holdings in Jamaica - this is w hat
makes them efficient. Inputs, processes and ou tputs are consistent,
reducing costs and improving profits. Production is purely for profit
and the result is increased food output. M achinery becomes almost
more important than employees.
The main commercial Caribbean products are sugar, bananas,
tobacco, rice, cotton, cocoa and coHee. Jamaica priori tises sugar
cane, bananas and coffee.
M arkets
The UK and mainland Europe are the main markets for Jamaica's (and
the Caribbean's) food exports. The British market used to be protected
for Caribbean bananas, but the World Trade Organization (WTO)
insisted Latin American producers be t rea ted equally after 2006. Sugar
prices vvere fixed at a much higher level than average global prices,
but again the VVTO has intervened to the detriment of Caribbean
producers. Caribbean rum was imported into Europe duty free and still
benefits from lovv duty. 1\/lontserrat and Curasao, as French and Dutch
overseas territories, have duty-free privileges on crops such as rice.
The fu t ure
Natu ral disasters have affected Jama ican farming during the 2000s,
reducing yields, and this may continue. Changes in European Union
(EU) policies remain a problem, alt hough the UK leavmg the EU may
be beneficial for Caribbean producers sinee Britain \,viii no longer be
controlled by EU rules.
In the fu ture, sugar will become t he key crop - 200,000 tonnes of
raw sugar per yea r - \,vith three products in different markets:
• Raw sugar is mainly exported.
• Molasses is used in rum manufactu re.
• Ethanol is produced for fuel - th is is t he likely growth area. Brazil
currently produces most ethanol for biofuel, but there is plenty of
futu re capacity.
Figure- 2, 19.4 Interior v'evv of a rum plant n Marie Galante
Recent changes in
Caribbean commercial
agriculture
Employment
LEARNING OUTCOME
In recent years there has been a decline in the number of individuals
employed ir1 agriculture (see figure 2.20. 1). The largest declines have
occurred ir1 the Dominican Republ ic, Guadelou pe and Martinique.
Significant declines have also occurred in Ba rbados and Puerto Rico.
• Under,tand the impact
of recent changes in
agricul ture- err ploymen1,
contributon to G)P, changes
in agrcultural land areas,
diversification and marketing
There are several factors responsible for the declir1e in ag ricultural
employment:
• Decreased agricultural production, for example sugar cane,
reducing job opportunities.
•• •
• Increased mechanisation replacing manual labour.
• Alternative better-paid employment in urban factories and in tourism.
The Turks and Caicos Islands
have the smallest percentage
of agncul tural land in the
Caribbean at i i.1st 1. 1 per cent
(2008). The ma ·n reason for
this is that the islands are very
rocky \~1ith poor soils and little
available fresh water. Tourism there are severa h,g h-class
resorts - is t he dominant activity,
prov1d ng many opportunities
for emp'oyment. Fishing,
particularly conch for export,
also employs a high number
o f workers.
'-1 1950
Bahamas
~
1;iiw1
Agricultural employmen t in Haiti declined from 85 per cent in 1950
to 62 per cent in 2000. Haiti is a poor country that still relies heavily
o n agriculture and has few machines or alternative jobs ir1 industry.
However, natural d isasters are a serious limitation . In 2010 there
were two earthq uakes in January, follo\'ved by Hurricane Tomas in
November. Hurricane Matthew also hit Haiti in October 2016.
In Trinidad and To bago relatively few individuals are employed in
agriculture owing to the large industrial sector based on the oil and
gas industry.
Contribution to GDP
Agriculture contributes about 25 per cent of g ross domestic product
(GDP) in the Caribbean, mostly from the export of major commercial
crops such as suga r cane and bananas . The contribu tion to GDP
is highest in Haiti (28 per cen t), Guyana
(25 per cent), Dominica (20 per cent) and the
Dominican Republic (1 1.5 per cent).
20 14- 15
I
'
Barbados
'
Cuba
Dominican
Republic
Haiti
I
I
I
I
Jamaica
Puerto Rico •
Trinidad and ~~
~~~~~_ _ _ __JL____J
Tobago .r:
0
10 20
30
40
50
60 70 80
Figure 2.20. 1 Changes n agricu ,tural employment
90 %
The trend in most countries is a fal I in
contribution to GDP O\'Ving to the expansion
of the service sector, pa rticularly based
on retailing and tourism, and the growth
of light manufacturing. For example, in
Barbados, the contribution has fallen from
38 per cent in 1958 to 6 per cent today. In
St Kitts and Nevis, it has fallen from 40 per
cent in 1 964 to less than 3 per cent today.
The rapid g ro>Nth in tourism is largely
responsible for these changes. Tourism offers
more a11ractive and less physically demand ing
employment .
Changes in agricultural
land area
The Caribbean accounts for j ust
0.25 per cent of the 'Norld's
agricultural land. Over 90 per cen t
of the region's agricultural land is
in Cuba, Haiti and the Dominican
Repu blic.
Look at Figure 2.20.2. No tice that
since 1981 there have been some
changes 1n agricultural land areas.
• Some coun tries, such as Cuba,
Dominica and Hai ti, have shown
an increase in agricultural land .
This may be because o f the
clearance of forests o r improving
la nd (by drainage or irrigation)
that \'Vas previously unsuitable for
farming .
• Some coun tries have shown a
significant decline in agricultu ral
la nd, such as Grenada, Puerto
Rico, St Kitts and Nevis and the
Virgin Islands (US) . This may be
because of the development of
tourism and the gro\,vth of bu 'ltup areas.
Food security
Country
Area
(thousand km' )
Percentage of
agricultural land
1981
2008
Antigua and Barbuda
0.4
27.3
29.5
Aruba
0.2
11.1
11 .1
Bahamas
14
1. 1
1.3
Barbados
0.4
44.2
44.2
Belize
23
4.3
6.7
Cayman Islands
0.3
11.3
11 .3
Cuba
111
55.3
62
Dominica
0.8
25.3
30.7
Dominican Republic
49
54.3
51.7
Grenada
0.3
47.1
35.3
Guya na
215
8.7
8.5
Hai ti
28
58.1
64.9
Jamaica
11
45.9
428
Puerto Rico
8.9
52.6
21.1
St '<itts and Nevis
0.4
57.7
19.6
St Lucia
0.6
32.8
18.0
St Vincent and
the Grenad ines
0.4
30.8
25.6
5
18.5
10.5
Turks and Caicos
0.9
1. 1
1. 1
Virgin Isla nds (US)
0.3
45.7
11.4
Trinidad and Tobago
Figure 2.20.21Changes n agricultural lar.d areas :n selected countr es
Women have a very importan t
role in local food production . They
g row food for t hemselves and
to sell to their ne·ghbours. This increases their incomes \,vhile also
allowing thei r neighbou rs to have food secu rity. While some women
have taken the o pportunity to commi t their working hours to food
production as a source of income, it is also possible for any woman
to produce o n a small scale alongside her normal job and/or domestic
responsibilities. The Kitchen Garden and Backyard Garden Projects
allow vvomen to receive training in growing organic fruits and
vegetables not o nly for home consum ption but also for sa le locally.
Diversification
Diversification involves developing alternative sources of income.
This might involve developing new markets for existing agricultural
products, for example using suga r cane as a source of fuel. It can also
involve growing different crops, such as introducing mixed farm ing
on sugar plantations .
Other forms of diversi fication include the development of farm shops
o r providing bed and brea kfast accommodatio n for tourists.
food security means that
everyone has access to
enough nutntioJs food at an
affordable price. During the
2000s CARICOM countries have
reduced production levels and
earnings from trad1t1onal crops,
increasing dependence on
imported food. As a result, some
people have become poorer
and have a poor diet, which can
lead to diet-related diseases. To
correct this there needs to be
increased support for small-scale
farmers producing local food .
Changes in marketing
Marketi ng agricultural produce usually involves one of two options:
1 Direct selling to the public at local markets, and to hotels,
restaurants and supermarkets. This has changed little over
the years.
2 Selling to companies and organisations, often for processing in
factories at home and abroad. This is the most common option
with commercial crops such as sugar cane, bananas, coffee and
cocoa.
In the past, most of the companies involved with agricultural
processing and export were foreign. This is because they had the
expertise and money to invest in the Caribbean.
In recent years, some Caribbean countries have reduced the influence
of foreign companies throug h nationalisation and sales to local
entrepreneurs. Now it is small farmers who dominate exports in crops
such as bananas in the Vl/indward Islands and yams in Jamaica.
Yam was never produced on
fore,g n-owned estates. It was
a,ways a small farmers' crop,
bu t as a result of divers'fication
it has become one of t he nontraditional exports, especially
to countries such as the USA,
Canada and the UK, \<Vhich have
many Jama·can imm ·grants.
Charities such as Fair Trade have had an increasingly important
influence in the Caribbean to ensure that farmers receive a fair retu rn
for their crops.
Biofuels
Biofuels are in increasing demand globally as a means to reduce
dependence on fossil fuels. This also encourages agricul tural
production in locations such as the Caribbean and Brazil. Sugar
cane is an ideal cro p to produce biofuels.
Brazil's economy now relies heavily on sugar-based biofuels for
its energy needs. Ethanol increasingly fuels vehicles. Not o nly
does the home economy gain from cheap, clean fuel, ethanol is
increasingly exported. In the future t he Caribbean could benefit in
a similar \<Vay.
Value-a dded
An increase in small-scale local production could lead to food
processing at cottage industry level. Both local and tourist markets
could be served. Cooperatives of local growers should receive
government support. Cooperatives reduce costs by members
purchasing and selling as a group . They can buy at lower prices and
sell at higher ones.
Technology and shade houses
Flat and undulating land is li mited in the Caribbean, so people are
forced to utilise steeper slopes. This limits the use of machinery
that might improve yields. Nevertheless, technology can o ffer
help in other 'Nays - shade houses have g reat po tential. These are
simple construc1ions that protect plants from the d irect glare of
the sun, reducing \'\later consumption ye1 increasing production
and income. Relatively cheap da rkened plastic materials are used to
minimise glare.
New markets
Changes in Eu ropean Union (EU) policies have limited the potential
of the Caribbean exporting to Eu ro pe. Brexit (the process of the
UK leaving the EU) may limit EU purchases, but the UK may \'Veil
·ndependently make new and beneficial agreements \'\11th CAR!COM .
Overall, Ca ribbean producers need 1o search for new markets w ithin
the reg ion and in North America. Costs of transport are minimal
w ithin a li mited area, plus the la rge-scale size o f the market may
bring increased security.
Impact of agriculture on economic development
in the Caribbean
Farming remains a major land use in t he
Caribbean, taking up more land than
any other economic ac1ivity. It produces,
on average, 24 per cent of the region's
GDP. In general, the poorer the country,
the g reater is t he proportion of income
from agricu lture. As jobs decrease in
this sector, they tend to increase in the
tertiary sec1or, in particular tourism.
Fig ure 2.20.3 shows employment
across the economic sectors in selected
Caribbean countries.
Country (in order
of agriculture as a
percentage of the
workforce)
(%)
Industry
(%)
Services,
including
tourism
(%)
Dominica
Cu ba
4 0.0
18 .0
32 .0
10 .0
28.0
72 .0
Jamaica
Barbados
Trinida d and Tobago
17.0
10.0
3.8
19 .0
15.0
33 .2
64.0
75.0
63.0
1.0
19 .0
80.0
Ag riculture
Virgin Isla nds
Figure 2.20.31 Employment across the econom,c seaors In se1ected
car bbean counmes
As exports such as sugar and bananas
decline, light ma nufacturing, tourism, offshore fi nancial and IT
sectors increase. W here agriculture has limitations, as in the drier
Leeward Islands, this process is faster than in more favoured
agricu ltural regions (e.g. the Windward Isla nds). Nevertheless, in nine
of the 1 5 CARICOM countries food produc1s account for 20 per cent
or more of their exports. In Dominica this represents 60 per cent of
export earnings. Bananas are the dominant crop.
Since 1970 farmla nd area has expanded in some Caribbean countries
and reduced in others. In Cuba, with the grea1est percentage and area
·ncrease, three million hectares o f new land have been brough1 in to
produc1ion, bucking the general trend of reduction of arable land .
Characteristics of commercial
sugar cane farming in the
Caribbean: Guyana
LEARNING OUTCOMES
• Understand the oevelopment
of sugar cane in the
Caribbean .
• Understand the characteristics
of suga r cane product:o n and
recent trends.
• Understand recent
diversification of products
and markets.
KEY TERMS
Sugar cane in the Caribbean
In 1961, sugar cane from the Caribbean accounted for 20 per cent of
world production. In recent decades this has fallen dramatically and it
is no~v less than 4 per cen t.
One of the main reasons for this decline ,s the high cost of
production and the fact that it can be produced elsewhere in the
world (from sugar beet) more cheaply. In addition, some plantation
land is being sold for tourist developments.
Cuba is the region's largest producer, accounting for 75 per cent o f
total harvest. Jamaica and Guyana are the other l\<VO major producers
in t he Caribbean .
Across the Caribbean, the sugar industry is still an important source
of foreig n income and it supports 150,000 unskilled and sem iskil led workers. In Barbados, sugar cane accounts for a third o f all
agricultural productio n by value.
Plantations: a large farm
estate that often concentrates
o n the prod uction of a
s ngle commercia cash crop.
Pla ntations usually have a large
amount of manua labour and
limited machinery. They may be
fore·gn-owned.
Sugar cane production
Sugar cane 1s a tall g rass growing to a height of 2.5-4.5 m. It can be
g rown on flat o r hilly land; if machinery is used, it is usually g rown on
flat land .
Sugar cane 1s harvested by hand or by harvester machines (see f igure
2.21 .1). The stumps are left in the ground for up to five years (new
canes, called ratoons, shoot from t hese stumps) before they are d ug
Caribbean sugar is mainly used for:
• exports to Europe, the USA and
to other CARICOM countries for
processing
• molasses for ru m and animal
feed.
•
•
•
•
Figure 2.21 .1 lv'echanlsed haNest'ng of sugar cane
up and replaced \'Vith new plants. Harvesting takes place during
the drier months after a growth period of between 8 months (for a
ratoon cane) and 18 months (for ne,N cane).
When cane is harvested by hand, the fields are of1en burned before
ha rvesting to destroy old leaves, get rid of pests and diseases and to
make it easier to harvest. Occasionally these fires burn out of con trol
and they can destroy cane that has yet to be harvested.
CASE STUDY
Suga r cane producfon in GJyana
Location
Ge~etown
Guyana is one of the la rgest suga r cane
producers in the Caribbean region. The ideal
location is along the eastern coastal strip, for
these reasons:
• The area has deep alluvial soil, with high
nutrien t content and a light texture for easy
cultivation.
• There is high rainfall - around 2,000 mm/
year - and suga r cane is a 'thirsty' crop. Two
\'Vet seasons per year mean h-vo crops can
be harvested annually.
• The coastal plain is densely populated,
providing plenty of labour.
• The coast road provides a key transport link
to the three ports of Georgeto\-vn, Skeldon
and Blairmont.
Sugar factories are located within the sugar
plantations, so the distance from harvest to
processing is minimal. As in Jamaica , both
large companies and medium-sized farms
produce sugar cane. They, too, are located
close to processing centres to minimise
transport costs.
In Guyana, sugar crea tes:
• 7 per cent of jobs
• 13 per cent of GDP
• 24 per cent of fore;gn exchange.
Farming methods
A network of canals \'Vith1in the plantations
allows easy, cheap transport. These also act as
a drainage system. Ho\-vever, some flood ing is
beneficial as the water washes un\-vanted salts
from the soil and adds new nutrients, reducing
the need for expensive artificial fertilisers. Pest
con trol has been improved by using biolog ical
methods (introducing predators), replacing high
LBL
Blalrmont
Albion
S~eldon
C Sugar estate
_ __:_;X Sugar factor,
PM for sugar
I°"~'"""Iexport
Figure 2 .21.2 Sugar prod1.;ct1on and processing loca1ions
'n Guyana
~;,itet: ,A!iJl3"1 lt4oO
usage of chemicals. This has an environmental
benefit.
Guyana employs less mecha nisation in sugar
production than many other parts of the
Caribbean. This is a result of its sugar often
being produced on gentle slopes. These help
good dramage but make use of machinery more
difficult. Some soils are too soft to support the
weight of heavy machinery. One set of plants
can produce up to five crops wi thin a short time,
then ploughing and replanting are needed .
The cane may be cut up into short lengths on site (see Figure 2.21.3)
before being transported (usually by road) to a processing factory.
~,.;;-.-.-....
/a-• _
} 73
~
Here, the cane is crushed and the juice is extracted. It is then purified
and heated to produce sugar crystals. The sugar crystals are treated
to form brown sugar, vvhich can then be packaged and exported . It is
further refined in the receiving country to produce w hite sugar.
Recent trends in sugar cane production
Recent trends in Caribbean sugar cane production include the
following:
• Increased use of machinery for planting, spraying and harvesting .
• Reduction 1n the production, ~vorkforce and la nd area plan ted with
sugar ca ne.
• Reduced involvement of foreign companies.
• Loss of preferential trade arrangements and protected markets.
• Increasing expense v;ith maintaining o r replacing old sugar-cane
refining infrastructure.
• Reductio n 111 available cane cutters as individuals move to vvork in
to\,vns and cities (ru ral depopulation).
• Sugar cane is also grown o n thousands o f small farms, yet most o f
these are unproductive, as they are too small to benefit from the
use of machinery.
Is diversification the way forward?
' n 1992, Caroni (1975} limited
decided 1o d 'versify into
aquaculture. freshwater ponds
were constructed to produce
Malaysian pra\,vns and cascadura
for export to Toronto, London
and New York. Cascadura are
high y valued fish In Tr'nidad
and Tobago. They live in murky
water, grow to a length o f about
1 Scm and have bony plate-Ile
scales to provide protective body
armour.
In the face o f increasing competition and falli ng dema nd for sugar, a
recent trend 1n the Caribbean has been diversification. This involves
finding alternative products and markets for sugar cane.
• A large number of products can be made from sugar cane,
including antibiotics, alcohol, vinegar and animal foods.
In Barbados, the authori ties are considering the use of sugar cane
bagasse to generate electnc1ty. In Brazil, sugar cane is used to
produce fuel for ca rs.
• In Trinidad and Tobago, Caro ni (1 975) Limited \'Vas the largest
company involved m sugar cane production . It was responsible
for producing over 90 per cent of Trinidad's sugar. In the 1980s
and 1990s it converted some of its sugar cane fields to growing
alternative commercial crops such as rice, ma ngos, pineapples and
nuts. Livestock >Nas reared using ani mal food made from sugar
cane and, in 1992, ponds were created to farm Malaysian prawns.
In 2003, the Trinidad and Tobago government closed do\,vn the
company owing to mounting debts. Some Caroni la nd has been
leased to 8,400 former Caroni workers to grow crops for local
consumption and niche crops for export, such as hot peppers
(Trinidad Daily Express).
Challenges facing the
Caribbean economies
Globalisation
A curren t process that no country's economy ca n avoid is
globalisation, w hich increases competition and makes markets more
difficult to find, affecting profits. For example, Euro pe \<Vas the key
market for Caribbean bananas and sugar, but 1oday other countries
such as Colombia, Peru, Ecuador, Panama, Brazil, Cote d 'Ivoire,
Cameroon and Ghana compete for the UK ma rket, lowering prices
and therefore profits. Wages for Caribbean workers fall as a result.
Trading together in groups helps Caribbean countries maintain
markets.
LEARNING OUTCOME
• Understand that Carbbean
econom es are facmg
chal enges assodated
w ith global sat o n, new
technologies, changing
rrarkets and the desire for
sustaina ble developrrent.
Some natio ns remain dependant o n particular crops. For example:
• sugar - Cuba, Guyana
• bauxite - Jamaica; bauxite earns more than 50 per cen1 o f the
export income (see Figure 2.22.2)
• bananas - the Windward Islands.
Relying o n a single product or two leaves a country's economy more
vulnerable.
Chinese investment in the Caribbean
China has invested billions of dollars in the Caribbea n by supporting
the development o f tourist projects, financing roads and port
developments and buying companies. This investment has provided
employment for constructio n \<Vorkers brought in from China and has
enabled l he Caribbea n economy to develop (see Figu re 2.22 .1). Little
local labour was used .
• In 2005, the Chinese governmen t spent US$55 million constructing
a brand ne\<V cricket stadiu m on the island o f Grenada in
preparatio n for the 2007 World Cup.
• In 2011, the Chinese governmen t announced an investment o f
USS2.4 bill ion in a new 3,800-room resort in the Bahamas that
would include the largest casino in the region. Some 5,000 Chinese
workers were involved in construction.
• Other investments announced in 201 1 inclu de port and harbour
improvemen ts in Suriname, resort development at Punta Perla in
the Dominican Repu blic and a US$ 17 million cricket stadiu m in
Dominica .
Many residen ts \<Velcome the increased investmen t and economic
ties w,th China. However, some are concerned that the massive
investment will lead to an influx of Chinese goods mto the Caribbean
and an increased influence o n the regio n's economy.
While globalisatio n has brought many advantages to the Canbbea n,
such as increasing in1ernational tourism and providing a greater
The Sea Island Cotton revival
was handicapped as seeds
\<Vere taken from Barbados and
cultivated In China, producing a
fibre tha t is o nly slightly shorter.
The quantity of this new cotton
made it competitive and the
price of Sea Island Cotto n o n the
Japanese market fell.
range of goods and services from
all over the vvorld, there have
been some disadvantages. Is the
distinctive character of the Caribbean
being eroded as it becomes more
internationa l? Some say that the
Caribbean is becoming more
Americanised, with basketball taking
over from cricket, burgers taking over
from trad itional cooking and rap
taking over from reggae.
Exploring for new resources
In Trinidad and To bago new gas fields
a re being discovered offshore which
will maintain production levels until
2050, but perhaps no t beyond that
date. Nevv exploration techniques,
though expensive, mea n that
resources previously seen as u nrealistic
could be workable and pro fita ble.
Technology
Technology has improved d rama tically in recent years, with the
advent of the internet and the use of sa tellites. Communica tions and
informa tion systems have been improved t hroughout the Caribbean.
Improvements in technology have provided new opportunities for the
Carib bean economy and many industries have benefited.
• Technology and increased mechanisation have led to improvemen ts
in efficiency in agriculture. Many industries, such as garments and
food processing, benefit from modern equipment.
• The internet has provided instan t access to information about
tourist opportunities in the Caribbean . 1\/lany companies rely upon
the internet for bookings.
Many Caribbean cou nlries are advertising products to appeal to
consumers in new and expanding ma rkets, such as:
• ecotou rism
• adventure tourism
• community tourism
• \'Vildlife trips
Figure 2.22.2 A baux,te processieg plant n
Jama1ca
• marriage on a Caribbean beach
• singles holidays.
Trading groups
Individ ual coun1ries 1end to have more bargaining power in trading
w hen 1hey belong to larger groups called trading blocs. For
example, many European countries belong to 1he European Union
and 1rade wi1h the rest of the world as a single bloc.
CARICOM \<Vas se1 up to represen11he interes1s of the Caribbean
region . Its main aims are to:
• increase trade bet\<Veen individual members
• encou rage 1he development of agricultural and industrial
businesses
• increase the range of goods and services being produced and
traded (some countries have become over-dependent on a single
commodity, e.g. bauxite in Jamaica and bananas in the Windward
Islands)
• remove tariffs (taxes) and q uotas (limits) on goods traded within
CARICOM and to establish the CARI COM Single Market Economy
(CS\ilE) to develop free 1rade within the region. Workers and
companies wou ld be able to set up in any country in 1he regio n and
there vvould be no taxes or quotas.
The majority o f 1rade takes place wi1h NAFTA (the North American
f ree Trade Association - USA, Mexico and Ca nada) and 1he Sou th
American trad ing blocs, LAIA (1he Latin Amencan Integ ration
Association) and Mercosur.
With 1he current trend of Chinese investment, Ch ina is becoming
an impor1an1 trading partner, wi th a 101 of 1he clothing, household
goods and electronic equipment in the Caribbean being made in
China.
Sustainable development
Sustainable development is important for the Caribbean's futu re
economic development. It aims to:
• meet the needs of the presen t withou1 compromising those of the
fu1u re- that is, manage resources effic'en11y without wast e, which
is especially important in the smaller Caribbean countries wi1h
limited natural resources
• improve quality of life and s1andard of living
• allow economic development wi1hout countries getting in1o deb t
• improve technology levels and 1rain people in the sk'lls to use them.
In 1996, McDonald's opened its
first restaurant 1n Bridge1own,
Barbados. Af1er jus1 six mon ths
1he restaurant closed do\<Vn
owing to lack of b~siness, \<Vith
loca Is preferring the taste o f
Bajan fish, ch•cken and pork 10
the 'b'and' burgers p roduced by
the restaurant cha·n. Today, the
res1auran1 bu ilding is home to
Consolida ted Finance.
Environmental degradation
in the Caribbean as a result
of economic activities
KEY TERMS
Deforestation: the total
removal o f trees and lowergrowing forest p.ants.
Forest degradat ion : da!T'age
to the forest, even destroct,o n.
,t occurs when primary
(ong,nal) forest is removed,
usually fo r timber exploi tation,
and smaller species take over
(secondary forest).
Deforestation
Damage to Caribbean forests began in earnest when Europeans
settled. Over time, the amount o f damage has been exponentia l (it
has been more serious as time has passed). Brazil lost 17.5 million
hectares of quality rainforest annually between 2000 and 2005
(the same area as Jamaica and Haiti combined).
Some Caribbean islands have lost very li1tle forest - the Bahamas,
Be ize, Dominica and Guyana, in particular. Haiti doesn't have a lo t o f
forested land (see Figure 2.23.1).
The main causes o f Caribbean deforestatio n are:
• Large-scale ag riculture - much forest was cleared fo r plantations
(coffee, co1ton, sugar) o r for large-scale cattle grazing. This was
mostly o n the coast since the produce had to be exported.
• Subsistence fa rming - clearance for this had happened over
centuries, but more recentfy population increase and demand
for food increased the ra te o f deforestation . M uch of Jamaica's
Blue Mounta ins have experienced this, though globally the vvorst
affected place is Brazil \<Vhere vast areas of forest have been cleared.
T
Per~ntage ol lo!al land area :ha: Is to,ested
in 1990 & 2011
0 1990
■
20 11
90% , - - - - - - - - - - - - - - - - - - - -- t
80% +---t
70%+---l
60%+---t
50% +-- -l
40% +---t
30% +---1
20%
10%
0%
Figure 2.23.1 Change n forest cover in the Caribbean, 1990 to 20 11
• Use of fuelwood and charcoal - all over the world poorer people
collect wood for fuel. This is especially true in Haiti (one o f the
poorest countries globally), Martinique, Guadeloupe and the
Dominican Republic.
• Logging for export - Guyana and
Belize export high-grade timber and
gain important foreign cu rrency as
a result. Secondary forest develops
afterwards. Large-scale businesses tend
to cause most damage.
• Mining - not only must forest be
cleared to access minerals, but
roads and airstrips are built to serve
these activities. Gold-mining has
caused damage in Guyana (see
Figure 2 .23 .2) and bauxile production
has contributed to more destruction
of forest in Jamaica than any other
economic activity.
• Ne,N budding - forest close to towns
has suffered as population grows
and demand for houses and services
increases. Tourism expansion leads
Figure 2.23.2 Destruction of rainforest cat.sed by gold minmg, Guyana
to new hotels and other facilities
plus infrastructure such as roads
and airports. Tou rists may come to
see the lush forests bu t they indirectly cause forest and \<Vildl'fe
destruction - the Puerto Rican pa rrot is threatened by inland
deforestation and coastal forest destruction in Guadeloupe means
fewer Hawksbill turtles.
Other results of Caribbean deforestation
Forests act as a water store in the water (hydro 1og·cal) cycle. The canopy
limits the impact of heavy rain on soil and tree roots hold soil together.
Deforestation therefore leads to soil erosion and to flooding. Resul ts
of natural disasters such as hurricanes are made worse. Unprolected
slopes suffer from landslides su fficien t to \'\lash villages away as in Haiti
in 2004 (Hurricane Jea nne) and 2010 (h urricane Tomas). Eroded soil is
washed o ffshore, silting up coral reefs and mang roves- again, these
are key tourist attractions as well as important wildlife sites.
Trees reta in carbon (they are referred to as 'carbon sinks') so their
destruction changes t he oxygen/ca rbon dioxide balance in the global
atmosphere, the consequence being global \'\/arming . Warmer seas
around the Caribbean ~viii likely increase the frequency and severity o f
hu rricanes.
Air pollution in the Caribbean
Compared with other parts of the wand, the Caribbean region's
air pollution is not too severe, though particular problems do exist.
Outputs from industry and vehicles produce the main air pollu tantscarbon dioxide, carbon monoxide, nitrogen oxides, sulphur compounds
Outputs o f CFCs (chloro- fluorocarbons), o r aerosol gases, can
reduce the upper atmosphere
ozone layer, allowing more
ultra-violet rays through and
threatening more people
w ith skin cancer. A European
Commission Report of 2013
also found that coral growth in
panama and Belize was limited
by aerosol emissions. Note that
these aerosol em1ss•ons do not
come from j ust the Caribbean
nations - this is a g!o t;ial issue.
and solid particulates such as soot. Power stations
based on fossil fuels (oil and natural gas) can emit
some harmful gases. Trinidad and Tobago is heavily
dependent on its fossil fuel resources, making it
the second highest global producer of greenhouse
gases per head of population.
Acid rain is the product of chemical pollutants
dissolving in atmospheric moisture. Landscape
damage from acid rain is serious (see
Figure 2.23.3):
•
•
•
•
Flgure 2.23.3 Trees ki led by acid rain and other po :lution
Forest and other plant growth is limited .
Rivers and lakes become acidic, killing wildlife.
Soil acidity increases.
Some building materials suffer from chemical
weathering, causing pit t'ng of the stone.
A natu ral ca use of air pollution is volcanic eruptions emitting gases,
dust and ash. The Soufriere Hills volcano in Montserrat caused
problems across the Caribbean between 1995 and 1997. Being a
stratovolcano, it emitted huge amounts of ash.
Polluion comes f•o11
1 Cailbbean Islands
2 USA - Gull of Mexico Coast
3 Cruise ships, oils 1an<11rs,
freighters
Inputs.
sources of
water polMlon
Ou1puts.
conseque,ces
of water pollunon
Deforeslatlon: soil +- __
Coral reef a + mangroves
slit washed Into sea
smothered
------- , Canbbean
Agriculture: pesbcldes + lertlBsers - - • offshore
water
was~ed Into rivers and then the sea
- • POllutJon
Sewage: 49% of homes iot - I • • \ \ \
•
cosnected 10 sewers: sewers
t
I I
I I
1
I
I I
\ \
I
ei,pensive to operate; much
J
J
I
I \
I
I
I
I
sewage Is pu11ped st,alght Into
\ \
\
I
I
I
\ I
\
I
I
I
the sea
I
I
\
t
I
I
I
I
I
OIi : - refinery waste + spillage
, 1
- ploellne damage
/
/
- splUs rrom accidents at sea /
,
- ships Illegally washing
/
/
out their oil ta~ks
/
,'
I
I
lnduatrlal waste: bauxrte ,
proces~ng waste - also paoer
makli g + pesticide production
1
,'
,'
I
Solid waste: -Iller lrom ships ,
- debris brought
down by rivers
\
\
1
,
Eutrophlcatlon: algae growth
In water reduces oxygen supply,
killing fish + omer wildlife
Wlldllle: suffer potsoolng - also
sorre eutrophlcatlon, as above - female
no,rrones affect wl!dllfe + cause gender
chMge Issues
\
•
WIidiife: dolphins. birds become coated
In oil + many dle-oU deMs washes up
on beaches + destroys tourist
environment
Water supply: bauxJte wasie gets
1
Into drinking + waste water trom pa;ier
\ makl~g contains chlorine. ma~ng
\ water highly acidic
\ \
\ \
\ \
\ _,.
I
• WIidiife: deDfis hurlS/~lls wlldltte who
may swallow 11 - poor appearance
of ll11er In sea
Figure 2.23.41VVater pollut on sources and consequences in the Caribbean
: I
Offshore water pollution
Caribbean countries need their surround ing seas to be clean.
Pollution hurts people's sta nda rd of living, landscapes and \<Vildlife.
Tourism is an important aspect of Caribbean income, so damage
to these environments could cost future income and economic
prosperity.
Much sea pollution drifts sou thwards from the USA. The BP oil spill
disaster in the Gulf of Mexico in 2010 caused damage in Caribbean
waters. American freight and tourist ships spill oil waste and drop
litter, as do cruise ships from elsewhere.
Figure 2.23.4 summarises water pollution ,n the Ca ribbean.
CASE STUDY
The lwokrama Project in cen1ral
Guyana promotes sustainable
use of tropical fores1 to achieve
ecolog ·cal, economic and soc'al
benefits for Guyana's people
and for the world in general.
Products being promoted
include: scientific research;
sustainable timber exploitation,
ecotourism; forest prodJcts such
as honey.
Measares to ensure the sustainable ma nagement -Qf resources: Guyana
Guyana has progressed further than many
Caribbean coJ ntries in terms of protecting
ecosystems, and therefore t he economy, from
pollution.
1 Tackling deforestation in Guyana
Guyana has several projects aiming to protect
and regenera te its rai nforest.
Forest Stewardship (simply, looking after
forest resources) promotes logging for
profit without destruction, while providing
1,500 jobs in Guyana. The forest Stewa rdship
Council (FSC) accredits businesses who
conserve the environmen t while utilising it.
To replace lost forest WWF (VVorldwide fund
for Nature, origmally a UK chanty) and t he
World Conservation Union replant local trees
to replace those lost m previous clearances.
Indigenous people are often involved, as in
Barima, Guyana.
2 Sustainable mangrove swamp
management
New resorts, marinas and coastal residential
areas linked to tourism are one reason why
the mangrove ecosystem is disappearing faster
tha n other forest environmen ts despite its
immense economic value. Tourists are attracted
by mangroves and their wildlife. Moreover, this
environment is an important breeding ground
for both commercial and game fish. Tourist
Figure 2.23.5 Nevv saplings grow,ng ,n a mangr<J>Je
nurse,y as part of Guyana's Mangrove
Acton Plan
boats often cause damage to mangrove roots
with anchors and propellers. Like rainforests,
mangroves are an important carbon sink
(a storage for carbon dioxide, limiting global
\'\/arming).
Guyana has a Ma ngrove Action Plan:
• New saplings (young trees) can be pla nted
to regenerate mangrove s1Namps. This helps
renew the ecosystem and protect coastlines
from coastal erosion (see Figure 2.23.5).
• Mangrove reserves allO\'V people to visit and
understand the importance of mang roves.
• Educational awareness programmes are run
for schools and colleges.
UNIT 2: Human systems
1 a Study the maps o f St Vincent (F gures 1 and
2) showing roads, physical features, and
ra:nfa II distribution.
Descri be 1he pattern of the roadways
on the Island.
(2)
11
b
State two reasons why fewer
persons would live ·n the interior of
the island.
(2)
Define the following terms:
popu lation density
ii
<200 m
□ 201-300m
Cl 301-500 m
D 501-700 m
Cl 101-soo m
• >900 m
(4)
population distr bution.
c
Describe how one historical factor has
influenced population distribution in a
named country.
(3)
d
Compare the population growth in the
Caribbean with either of Aus tra 'ia, China or
Nigeria using the headings:
birth rate
•
ii
iii
2 a
life expectancy
(9)
government policies.
Study t he popu lation pyramid for Haiti
(=igure 3) and answer t he following
questions:
Figure 1
Topography and road network o'
'--=-----' St V ncent
Annual Rainfall
15
•
•
ll!IY~lh~
Figure 3
m
l
11!
0
0
t
1ffl
m •
P II
•M
51.
:If
t nh
Population pyramid fer Ha ti
$¢:1ttt: IJS Q111u, !lu·t.11.:. 2(1 16
Did Hai ti have a high birth rate in
2016? Justify your answer.
MIiiimetres
D
D
D
D
aver3.ooo
2.500-3.ooo
2.000-2,500
Be'ow2.000
-
Pm1al!!ng Winds
4
Figure 2
8
ii
12
b
16 ijlomeues
Annua ramfal n St V1~cent
$«..-<'t: n11~/N,Vl\'I 11'11~~0"/ <::>~\"SM'•"l(tf'I MOU( 1t•
\161) MM:fl'\','.'Jr; Cfl,Ol>N" AfldS
(2)
What evidence on the population
pyram id indicates a reduction in the
rate of natural increase?
(2)
For the growth of urban population in a
Caribbean coun try that you have studied,
explain two causes of the popu ation
grovvth
(4)
ii
explain !:>No benefits of the population
growth.
(4)
c
11
3a
5 a
For a Caribbean cou ntry that you have
studied,
b
explain t\,vo reasons for
lmm,gra tion
(4)
explain two consequences of
emigrafon.
(4)
Define the term 'subsis1ence farming'.
Describe how 1he follow;ng factors have
influenced the development of agriculture
in the Caribbean:
historical
ii
iii
Draw a graph or <;1 chart us·ng the
information provided in Figure 4.
(4)
c
6.2
lndustrv
Services
Figure 4
ii
14.3
79.5
( lrriponaoce of each economic sector in
' 2015
Grenada 1n
Sovroe: TIit C,'A '11<).•,"d faei~ci: 10~6 e"d ¢lh,:11¢Ut(h
b
c
Define the 1erm 'primary economic
activities'.
(2)
Define the term 'secondary economic
activities'.
(2)
d
Describe t\,vo characteristics of tertiary
economic activi ties.
(4)
e
Explain how each of the following factors
has influenced the location of fishing or
natural gas or food processing within
CARICOM and Singapore:
i
energy
ii
iii
capital
markets
1v
the role of government.
compare the characteristics of largescale and small-sca ,e commercial
farming t hat is practised in the country
drawn in (c) (i) above under the
head ings:
b
farm size
Downership
c
markets.
a
6 a
b
(9)
Draw a ske1ch map of a Caribbean territory
and insert the major sugar cane gro\'\ling
a~s.
~
Describe changes in sugar cane farming
pr;ic1ices 1n Guyana in the last 20 years
under the headings:
government policy
11
111
value-added products
new markets.
(6)
(8)
7 a
4 a
(9)
draw a sketch map and oca te areas of
large-scale and small-scale commercial
farming.
(5)
Year: 2015
Agricul1ure
physical
human.
For a coun try that you have studied,
Percentage contribution to GOP
Sector
(2)
Draw a ske1ch map of a Caribbean cou ntry
and ndica te t\,vo areas w here tourism
is the ma1or economic act vity.
(5)
b
Explain w hy tourism facili1 es have
developed at the two sites shown in the
map n the named country above.
(5)
C
What are tvvo benefi ts of tourism
Caribbean?
in
the
(2)
d
What are two probtems caused by tourrsm
in the Caribbean?
(2)
e
Explain three ways in which ecotourism
may cause environmental degradation . (6)
Describe two ways in w hich tourisl"1 in the
Caribbean has caused ...
1
ii
b
positive env:ronmental development
negative environmental effects.
(4)
Explain two measures that can be taken to
ensure sustainable managemen t of tourism
resources a1 each of the following levels:
regional
ii
iii
na tional
personal.
(6)
A
abiotic (non-living) environment 55
abrasion 78
adventure tourism 156
ageing populations 130
agriculture 160
agricuhural land use in the
caribbean 162-3
biofuels 170
changes in agricultural land
area 169
changes in marketing 170
comparison of farming in
Jamaica 165
con tribution to GDP (gross
domestic product) 168
diversification 169-70, 174
employment 168
food securi ty 169
future challenges 167
Impact on economic development
in the Caribbean 17 1
importance of agricul ture in the
caribbean 160-1
Jamaica's farming practices and
products 166
labour, capital and technology in
Jamaica 166
lard ownership and size of farm in
Jamaica 166
markets 167
new markets 171
patterns of land use in Jamaica
164-5
recent trends 1n Caribbean
agricul ture 163
sugar cane in the Caribbean
172-4
technology and shade houses 171
value-added 170
aid 97
air pollution 179-80
altitude 33
an11cyclones 38, 40
aquifers 62-3
arable farming 161
arches 81-2
Arctic ice covet 46
arcuate deltas 75
ashfalls 98
attrition 68, 78
B
bars 72, 85
barrier bars 85
batholiths 12
bauxite 141
184
. ·.
bays 81
bay bars 85
bayhead beaches 82
beaches 82-3
biodiversity 93-4
biofuels 170
biomes 54
tropical rainforest 56-63
biotic (biological) weathering 21
biotic (living) environment 54
bird's foot deltas 75
birth rate 118
braiding 73--4
breezes 34
C
calcareous rock 24
calcium carbonate 24
call centres 139, 158-9
capital 143
carbon dioxide 47
carbon offset payments 52
carbon sin~s 63
carbon trading 51
carbonation 20, 25
Carboniferous limesmne 24
Caribbean Disaster Emergency
Management Agency
(CDEMA) I 06
Caribbean Disaster Emergency
Response Agency (CDERA) 105
Caribbean plate 6-7
formation of the Lesser Antilles
volcanic arc 7
CARICOM (Caribbean Communi ty and
Common Market) 148-5 1, 177
caverns 27
caves 27
Harrison's Cave, Barbados 29
sea caves 81-2
chalk 24
check dams 106
chemical weathering 20-1
child mortality 118
chloropleth maps 114
cli ffs 80-1
climate 30, 11 5
climate in the Caribbean 30-1
climate protection payments 51
distance from the sea 33
ecosystems 54-5
equatorial climate 36
factors affecting climate 32-4
factors affecting climate in St Lucia
34-5
rainforest 56-7
tropical marine climate 37
coast, proxi mity 115
coastal erosion 78
sediment transport and deposition
78-9
coastal landforms 80
bars 85
beaches 82-3
caves, arches and stacks 81-2
cliffs 80-1
headlands and bays 81
low-tide platforms 81
mudflats 84
spits 84
tombolos 84
wave-cut platforms 80-1
cockpit karst landscapes 28, 29
cold fronts 40
collision margins 5
commercial agricul ture 161
commercial plantations 160
community responses to disasters
104-5
community tourism 156
condensation 66
congestion 130
constructive plate margins 4
continental crust 2
continental drift 2
continentaliiy 33
conurbations 133
convection currents 3
convergent boundaries 4
coral reefs 88
atoll reefs 89
barrier reels 89
coral formation 89-90
deforestation 62
fringing reefs 88
importance of coral reels 91
corrasion 68, 78
crime 130
crude oil see oil
D
dams 106
death rate 118
decentralisation 134
deforestation 61-2
air pollu tion in the Caribbean
179-80
damage to coral reefs 62
decline in aquifers 62-3
ecological damage 63
environmental impacts in the
Caribbean 179
exponen tial damage in the
caribbean 178-9
floods 62
global impact 63
Hait, 62
Jamaica 63
offshore water pollution 181
soil erosion 62
soil exhaus,,on 62
tackling deforestation in
Guyana 181
tourism 63
deltas 75
demographic transition model
119-21
population pyramids 123
dendri tic drainage 86
denudation 18
deposition 69, 78-9
destructive plate margins 4
dew point 66
distributaries 75
divergent boundaries 4
dot maps 11 2-13
drainage basin hydrological cycle 67
drainage patterns 86-7
drains 107
dykes, volcanic 12
swarms 12
E
Earth 2
core 2
crust 2
mantle 2
plates 2-3
earthquakes 5, 7, 8, 96, 97
better buildings 107-8
earthquakes in the Caribbean 100
eplcenue 8
faults 8
focus 8
Haiti 20 10 earthquake 101
hazards 100-1
landslides 22, 100
seismic waves 8
ecology 93-4
deforestation 63
economic activity 138
Chinese investment in the
Caribbean 17S-6
economic sectors in the
Caribbean 139
exploring for new resources 176
globalisation 17 5
impact of agricul ture on the
Caribbean economy 171
importance of economic sectors
138-9
primary sector 138, t 39, 146-7
quaternary sector 138, t 39,
158-9
secondary sector 138, 139,
148-51
sustainable development 177
technology 176
tertiary sector 138, 139, 152-7
trading groups 177
ecosystems 54
components 54
imoortance of biotic conditions 55
importance of climate 54-5
lmoortance of soils 55
nutrient recycling 54
ecotourism 156
Belize 157
Black Rock Lodge, Belize 157
emigrants 136
emigration 118
Jamaica 137
energy 143
energy conservation 52
enhanced greenhouse effect 47
environmental quality 143
epiphytes 59
equatorial climate 36
erosion 18
coastal erosion 78-85
deforestation 62
river erosion 25, 68-9
evaporation 66
exfoliation 19
expertise provision 139
extensive agriculture 161
extrusive volcanic features 12-13
extrusive volcanic landscapes
14-15
volcanic plugs 15
F
farming see agriculture
faults 8
major faults 11
finite resources 140
fishing 141, 144
Belize 145
fish pots 144
future challenges 145
how are fish marketed? 145
long lines 144
seining 144
trawling 144
why is fishing important in the
Caribbean? 144-5
flood plains 74
floods 96
deforestation 62
reducing flood hazards 106-7
flows 66
fluvial precesses 68
deposition 69
erosion 68-9
transportation 68
fold mountains 10, 11
food processing 148
advantages of the Caribbean for
food orocessing 149
challenges for food processing in
the Caribbean 149-50
challenges for the future for food
processing in Singapore 151
differences be~Neen Singapore and
CARICOM countries 151
food processing in Singapore
150-1
future of food processing in
CARICOM countries 1 50
Guyana 149
Jama,ca 148-9
location of factories 148
similarities between Singapore and
CARICOM countries 151
types of food processing 148
food production, decreasing 130
food security 169
footloose industries 158
forced migra1ion 136
Forest Stewardship Council (FSC) 61
fores1s 140- 1
forest degradation 178
friction 76
fronts 40
frost ac,,on 18-19, 25
G
gabions 106
gas see natural gas
gases 64
GDP (gross oomestic p•oduct) 168
glaciers 47
global atmospheric circulation 38
global warming 30, 46
advantages 48-9
caribbean 49
disadvantages 49
effects 48
evidence fo· 46-7
human activities 47
naiural causes 47
reducing greenhouse gas emissions
50-1
UK responses 52- 3
USA49
globalisation 175
gold 142-3
gorges 26, 27, 71
government policies 143
green belts 134
green movement 52
greenhouse effect 47
greenhouse gases 47
carbon trading 51
climate protection payments 51
green policies 1n the UK 52-3
reducing emissions 50
renewable energy in ;he
Caribbean 51
grid-square urban road layouts 133
ground shaking 100
Ju,assic limestone 24
H
K
Hadley Cells 38, 39
headlands 81
heat island effect 30
hooks 84
housing problems 130, 133
humus 55
hurricanes 42, 96
effects of hurricanes 44
how do hurricanes develop? 42-3
hurricane hazaros 102-3
hurricanes in the Caribbean
102-3
issuing warnings 109
reducing hurricane hazards 45,
108-9
tracking hurricanes 109
what forms a hurricane? 41
hydraulic action 68, 78
hydrological cycle 66
drainage basin hyd rological
cycle 67
hydrolysis 2(}-1
ka~t landscapes 28-9
Kingston, Jamaica 132
population growth 132
problems of urban growth 133
urban landscaoe 133
I
ice cores 46
ICT industries in 1he Caribbean 158
Costa Rica 158-9
Haiti 158
Jamaica 158
igneous rocks 16, 17
immigrants 13 6
immigration 118
Cayman lslanos 137
industry 143
infant mortality 118
infinite resources 140
information provision 139
inorganic matter 64
insolation 47
instrument readings 46
intensive agricul ture 161
Inter Tropical Convergence Zone
{ITCZJ 38, 39
intrusive volcanic features 12
intrusive volcanic landscapes 14
investment 134, 145
Chinese investment ,n the
Caribbean t 75-6
island arcs 1O
formation of the Lesser Antilles
volcan,c arc 7
lwokrama Project 61, 181
J
L
labour 143
laccolitns 12
lahars 98
landslides 22-3, 96, 98, 100
landslide prevention 107
latitude 32
latosols 64-5
lava 4, 12
acid lava 13
basic lava 13
lava plateaux 13
leaching 57
levees 74-5, 106
lianas 59
life expectancy 118
limestone 17, 142
characteristics 24-5
formation 24
grykes and dints 26
limestone landscapes 26
limestone pavements 26
processes 25
surface landforms 26-7
tropical karst landscapes 28-9
underground landforms 27
liquefaction 100
liquids 64
load 69
long-line fishing 144
long-wave radiation 47
longshore drift 79
low-tide platforms 81
M
magma 4, 13
mangrove wetlands 92, 145
biodiversity 93-4
Black River Lower Morass,
Jamaica 95
Caribbean mangrove we1land
ecosystems 92-3
coastal protection 93
importance 93-5
socio-economic benefits 94
sustainable management in
Guyana 181
manufacturing 139
markets 143
mass movement 22, 25
landslides 22-3
soil creep 23
meanders 72
meander migration 72
metamorphic rocks 16, 17
methane 47, 49
microclimates 30
mid-oceanic ridges 4
migration 118, 136
circulation 136
international migration in the
Caribbean 136-7
minerals 55, 64
mining 179
landslides 23
monocultures 166
mudflats 84
mudflows 22
N
national responses to disasters I 05
natural change 118
natural decrease 118
natural disasters 96
natural gas 141 , 146
challenges for the future 147
extraction 146-7
formation and discovery 146
importance 147
markets 147
Trinidad and Tobago 146-7
natural hazards 96
aid 97
earthquakes 96, 1Q(}-1
floods and storm surges 96
hazard mapping 108
hurricanes 96, I 02-3
landslides 96
long-term responses 97, 104-5
managing natural hazards 106-9
national responses 105
natural hazards in the
Caribbean 96
regional responses 105-6
short-term responses 97, 104
trends in natural hazards 96-7
volcanoes 96. 98-9
natural increase 118
rapid natural increase 128
nitrous oxide 47
non-renewable resources 140, 147
northers 40
nutrients 54
0
ocean trenches 1O
oceanic crust 2
Office of Disaster Preoaredness and
Emergency Management (ODPEM)
105
offshore waier pollution 181
oil141,146
challenges for tne future 147
extraction 146-7
formation and discovery 146
imporiance 147
markets 147
Trindad and Tobago 146-7
oolitic limestone 24
organic matter 55
organisms 64
over-fishing 145
oxbow lakes 72-3
global pcpulalion density 113- 14
population disttibution in the
Caribbean 116
Jamaica 116-17
population growth in China 125-7
population growth in Jamaica 124-5
Kings1on 132-3
population pyramids 122
comparing population pyramids
122
demographic ttansition model 123
Jamaica 122
potholes 70
pract,ce exam questions 110-11,
182- 3
precipi tation 66
pressure release 19
prevailing winds 77
primary economic sector 138, 139
crude oll and natural gas in
Trinidad and Tobago 146-7
primary forest 178
primate cities 131
cores 131
Kingston, Jamaica 132-3
peripheries 131
pull fac1ors 128, 129
push factors 128
pyroclast,c flows 98
Q
quaternary economic sector 138, 139
call centres 158-9
p
pastoral farming 161
paved drains 107
ohysical geography 114
physical weathering 18- 19
pillars 27
plate tectonics 2-3
Caribbean plate 6-7
collision margins 5
convergent boundaries 4
divergent boundaries 4
evidence for plale tectonics 3
plate movement 3
transform boundaries 5
ooin t bars 72
pollution 145
population change 118-19
demographic transition model
11 9-21
population distribution 112
chloropleth maps 114
dot maps 112-1 3
factors affecting population
distribution and density 114-15
R
radial drainage 86-7
radiation 47
rainfall 102
landslides 22
rainforest 56
climate 56-7
deforestation 61-3
lower canopy 59
middle canopy 59
shrub and ground layer 59
soils 57
stratification 58
sustainable management 60
sustainable management in
Guyana 60-1, 181
top canopy 58
vegetation 58
rainshadow 35
rapids 70-1
raw materials 139, 143
reafforestation 60-1
recycling 52
regional responses to disas1ers 105-6
relief 33, 143
renewable energy 53
renewable resources 140
resources 115
exploring for new resources 176
factors affecting the location of
industry 143
non-renewable resources 140, 147
renewable resources 140
resources in tbe Caribbean 140-3
resurgences 27
risk 96
rivers 68-9. 11 5
drainage patterns 86-7
river cliffs 72
river erosion 25, 68-9
river landforms 70-5
river valleys 70
underground rivers 27
rock cycle 16-17
rural depopulation 130
rural Investment 134
rural-urban migration 128-9
5
saltmarshes 84
sa1ellite monitoring 61
saturation 66
sea-floor spreading 3, 15
sea pollutton 181
secondary economic sector 138, 139
food processing in the Caribbean
148-51
secondary forest 178
sed1memary rocks 16, 17
seining 144
services 139
se,vice loss 130
shade houses 170
short-wave radiation 47
sills 12
small-scale family farms 160
soils 55, 64
constituen ts 64
latosols 64--5
rain forest 57
soil creep 23
soil exhaus1ion 62
solu tion 69, 78
Soufriere Hills, Montserrat 99
spits 84
stacks 81-2
stalactites 27
stalagmites 27
stores 66
storm surges 96, 103
stratification 58
stumps 82
subduction zones 4
subsistence agriculture 161
sugar cane production 172-4
diversification 174
recent trends 174
sugar cane production in
Guyana 172
summer 39
sustainable development 157, 177
swallow-holes 27
T
technology 176
telecommunications in the Caribbean
158-9
tertiary economic sector 138, 139
tourism in the Caribbean 152-7
tombolos 84
tourism 152
advantages and disadvantages 155
attractions of the Caribbean 153
deforestation 63
importance of tourism 152-3
Jamaica 156
rapid g,ow1h in recent years 153
trends in tourism 154-5
tower karst landscapes 29
trade winds, north-east 40, 76, 77
trading blocs 177
transform plate boundaries 5
transnational companies (TNCs) t 47
transport 130, 133, 143
transportatio~ 68, 78-9
trawling 144
trees 55, 57
emergents 58
trellised drainage 86-7
tropical karst landscapes 28-9
188
.·.
tropical marine climate 37
tropical rainforest 56-63
tropical waves 41
tsunamis 7 6, 1O1
u
urban corridors 134
urban growth 128
urban poverty 130, 133
urban sprawl 130, 133
urbanisation 128
Barbados and Cuba 134--5
imoacts of urbanisation 130
primate cities 131
problems of urbanisation 134-5
rural-urban migration 128-9
urbanisation in the caribbean 129
V
valle~·s 27, 70
dry valleys 2 6
V-shaped valleys 70
vehicle emissions 53
volca~oes 8-9, 12, 96
calderas 13
composite volcanoes 12-13
extrusive features 12-13, 14-15
hazard risk mapping, St Kitts 107
hot-spots 9
intrusive features 12, 14
landslides 22, 98
lava plateaux 13
Pacific Ring of Fire 9
shield volcanoes 12-13
vents 12
volcanic hazards 98
volcanoes in the Caribbean 98-9
voluntary migration 136
vulnerability 96
w
water 66
water vapour 66
see hydrological cycle
waterfalls 71
waves 76
constructive waves 77
destructive waves 77
fetch 76
wave refraction 82, 83
wave-cut notches 80
wave-cut platforms 80-1
what causes waves to break> 76-7
winds and waves in the
Caribbean 77
weather 30
anticyclones 38, 40
distance from the sea 33
factors affecting weather 32-4
factors affecting weather in
St Lucia 34-5
fronts 40
global atmospheric circulation 38
hurricanes 42-5
tropical waves 41
weather in the Caribbean 30,
38,39
weathering 18
biotic (biological) weathering 21
chemical weathering 20-1
limestone 25
physical wea1hering 18-19
winds 33, 102
anticyclones 38, 40
land and sea breezes 34
prevailing winds 77
1rade winds, north-east 40, 76, 77
winds and waves in the Caribbean
77
winter 39
Study Guide
OXFORD
VN IVERSITY PRESS
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ISBN 978-0-19-841386-8
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