G107 Summary Part I
Draft draft draft
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Introduction
 Geography is the study of the distributions
(locations) and interrelationships of Earth
phenomena (causes and consequences)…
Geography is the study of the Earth (space,
spatial location,and theme being studied)
 Geography is divided into Physical and
Historical
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Physical Geography
 Deals with locational aspect of natural
materials
 It involves weather, climate, landforms and
water bodies, vegetation, and soils
 Two questions are important in physical
geography- Where (location) and Why
(process)
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Map
 A 2-D representation of three dimensional
surface features
 Small scale map covers large area
 Large scale map covers small area
 Three ways to represent scales in a map
– Written or verbal
– Representative fraction (RF)
– Graphic
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Scientific Methods
 Five general steps
 Problem or Questions
 Hypothesis
 Collection of data
 Testing of hypothesis
 Theory
– Theories can be modified or discarded
 Law- usually cannot be falsified
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Fundamental Themes in
Geography
 Location
 Place
 Regions
 Movement
 Human and the environment
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Proof for the Sphericity of Earth
 Travel in a given direction
 See curvature
 Sailing Boat
 Use of three sticks
 Higher you are, the more area you see
 Eclipse
 Satellite pictures
 Gravity data
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Size of Earth
 Earth is oblate spheroid so the polar
diameter is different from equatorial
diameter
 Polar diameter is 12,714 km (7900 mi)
 Equatorial diameter is 12,757 km (7927 mi)
 Polar circumference is 40,008 km (24,860
mi)
 Equatorial circumference is 40,075 km
(24,902 mi)
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Movement of Earth
 Rotation and Revolution
 Rotation- earth rotates west to east and
when looked on from the north pole is
counter clockwise or from the south pole –
clockwise
 Rotation occurs around an imaginary lineAXIS that has 23.5 degrees tilt
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Consequences of Earth’s Rotation
 Daily or diurnal rhythm phenomena
Light, heat, humidity, air motion, and
DAY & NIGHT
 Coriolis effect
 Tides and shape of the Earth
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Time Zones
 Takes the earth 24 hours to make one complete
rotation (inscribing 360 degrees)
 Takes the earth 1 hour to cover every 15 degrees ,
so can divide the world into 24 time zones
 N. America has 7 time zones, USA has 6 and the
48 contiguous states have four time zones.
 International Dateline follows approximately
Longitude 180.. What happens when you cross the
dateline?
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Seasons
 Why 4 seasons in Ft. Wayne?
 Tilted axis, Fixed axis, Rotation, and Revolution
 The four seasons
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Imaginary lines
 Longitude and Latitudes are imaginary lines needed to
locate oneself in a map
 Lines of Longitude run north –south
– All lines of longitudes are Great Circles and the
reference line Prime Meridian or Greenwich Meridian
– Longitudes are measured east or west of the reference
line
– The distance between two adjacent lines of longitude is
111 km at the equator, 96 km at 30; 56 at 60 and o at 90
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Imaginary lines
 Longitude and Latitudes are imaginary lines
needed to locate oneself in a map
 Latitudes run east – west
– Equator is the reference line and they are
measured north or south of the reference line
– Latitudes are also known as lines of parallel.
– Only the Equator is a Great Circle
– The distance between two adjacent lines of
latitude is 111 km.
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Material Realms or Spheres
 Lithosphere
 Biosphere
 Hydrosphere
 Atmosphere
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Atmosphere
 Envelope of air around the Earth
 Atmosphere can be classified using composition,
function or temperature
 Make-up of the atmosphere
– Variable –CO2, H2O, O3, H
– Non variable gases
• N (78%), O (21%), Ar (0.9%) & Ne (0.002%)
 Classification of the Atmosphere using
temperature
– Troposphere, Stratosphere, Mesosphere, &
Thermosphere
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Ozone
 Importance of Ozone
 Removes harmful UV radiation
 When not present
– Can lead to increase in skin cancer
– Decrease in crop yield
– Kills certain aquatic life forms
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Global Energy
 Flow of energy from the sun is fairly
constant
 Radiation from the sun is made up of
different wavelengths
– Divided into 3 regions- UV, Visible,and IR
• Visible range is between 0.4 um and 0.7 um
 Sun’s spectrum is short wave length
compared to the earth’s spectrum
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Albedo & Others
 The % of energy reflected from a surface
 A good reflector has high albedo
 Greatest energy lost occurs as radiation
passes through the clouds
 Temperature and heat energy
 How is heat transferred?
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Heat Transfer
 Conduction- requires solid
 Advection- requires gas or liquid
 Convection- requires gas or liquid
 Radiation- requires no medium
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Temperature
 Fahrenheit
 Centigrade
 Kelvin
Copyright by Isiorho. Draft prepared Mmay 22,
2001
Possible questions?
 Map scales, latitudes and radiation, heat
transfer, time zones, atmospheric layers,
ozone, great circles, mountain slope- which
will receive more radiation, albedo, heat
trapping ability, shape of earth, meridian,
equator, wavelength, electromagnetic,
planets, dateline, reduction of solar
radiation, visible range, theories, distance
between latitudes and longitudes, nitrogen,
oxygen, Antarctic circle, etc.
Copyright by Isiorho. Draft prepared Mmay 22,
2001