A Guide to:
The End of the World
Everything you never wanted to know
By
Richard O’Sullivan
Foreword – where will it all end?
• For definite, 5 billion years from now,
when the Sun runs out of hydrogen, swells
to a huge red giant – burns earth to cinder!
• Disease, warfare, natural catastrophe, and
exotic physics experiments gone wrong are
some others.
Questions?
Nearly two millennia ago the disciples of Jesus of
Nazareth asked Him a question that has intrigued
people ever since:
"What shall be the sign of thy coming, and of the
end of the world?" (Matthew 24:3, King James
Version).
But it’s not just religious people who are asking…
politicians, educators and scientists.
Contents
•
•
•
•
Introduction to the Earth
Global Warming: A Lot of Hot Air?
The Ice Age Cometh
The Enemy Within: Super-eruptions, Giant
Tsunami, and the Coming Great Quake
• The Threat from Space: Asteroid and
Comet Impacts
• Conclusion
Introduction
Synopsis
The Earth can be described as:
• extraordinarily fragile
• dynamic
• dangerous
NB: the very things that helped
make the Earth so life-giving
have the potential to take it
away (volcanoes, precipitation)
Only 10,000 years after the end of
the Ice Age, the planet is
sweltering in some of the
highest temperatures it has
ever experienced.
At the same time, overpopulation
and exploitation are
dramatically increasing the
vulnerability of modern society
to natural catastrophes such as
earthquakes, floods and
volcanic eruptions.
Introduction
• Everything that will happen has happened before.
• Imagine the Earth’s history as a 1500m (3.5lap)
race…
• First lap = barren wasteland of impacting asteroids
and exploding volcanoes.
• Second lap = planet begins to cool, allowing oceans
to develop and simplest life forms to appear.
• Final straight = Cambrian: explosion of diverse life
forms. Dinosaurs appear at the battle for the tape and
then disappear while leaders are 25m from the finish.
• NB: our most distant ancestors only appear in last
split-second, just as the winner breasts the tape.
Introduction
Thousands of people die
every year from floods,
volcanic eruptions,
earthquakes, hurricanes
and typhoons.
Yet compared to what the
Earth endured in
prehistoric times - lethal
volcanic winters, deadly
asteroid collisions - our
civilization has developed
against a backdrop of
relative geological calm.
Will this calm last?
At least 15 million deaths in
the last millennium are
attributed to natural
hazards.
96% of all deaths from
natural hazards and
environmental
degradation now occur in
developing countries.
But, 75% of all economic
losses are in developed
countries.
Global Warming
A Lot of Hot Air?
Debate – what debate?
• Global warming is about much more than hotter
summers, winter floods, and farting cows.
• But the evidence is irrefutable: human activities
are driving the current period of planetary
warming.
• Only few maverick scientists, oil company reps,
and George W. Bush that don’t think so.
The Great Global Warming
Experiment
• Earth is now warmer than
it has been for over 90%
of its 4.6 billion year
history.
• By the end of the 21st
century our planet may
see higher temps than at
any other time for the last
150,000 years.
• This century the decade
of the 1990’s has been the
hottest (all across the
planet as a whole).
• These are some of the
ways in which the climate
can be affected:
• Variations is the Suns
output – Sunspot Cycle
• Gas emissions
• Volcanoes
• Nuclear testing
Hothouse Earth
•
•
•
•
•
•
By 2100, global temps are
forecast to rise by up to 8ºC over
land, with sea levels up to 88cm
higher.
CO² conc. in the atmosphere will
be higher than at any time in the
last 20 million years.
By 2025, 5 billion people will
live in countries with inadequate
water supplies
In 50 years all the world’s great
reefs will have gone due to high
sea temps.
No more winter sports in 2100
If the Greenland Ice Sheet melts,
coastal cities will be drowned
(NYC, London, Sydney).
Good, bad and the downright mad
• Kyoto Protocol (1997)
• Aimed at a 5.2% reduction in
greenhouse gas emissions
(below 1990 levels) by 200812.
• But due to the US not buying
in, the world’s greatest
polluter, emitting a quarter of
all greenhouse gases (along
with their partners in crime,
Australia and Canada – back to
square one.
• But the Kyoto Protocol will
have little impact – reductions
in emissions of the order of
60% are needed now.
• Contraction & Convergence
(C&C)
• Thought up by London’s
Global Commons Institute
• 2 principles: greenhouse gases
must be reduced and must be
fair to all
• Will reduce emissions on a per
capita basis. Each country
having a permit, and these
would be tradable.
• Countries such as US and
Australia that could not
manage with their allocations
could buy extra ones from
developing countries with a
surplus.
The Ice Age Cometh
Fire or Ice?
• How do you want your children’s children to die,
fry or freeze?
• When can we expect the next Ice Age – very
soon!
• Some say that the anthropogenic (man-made)
warming and its associated climatic impact may
be delaying it, or even fending it off.
• Therefore we should embrace GW?? In other
words, how do wish our contemporary world to
end – by fire or by ice?
How to freeze a planet
• During the Cryogenian
(after cryogen for
freezing mixture)
between 800 and 600
million years ago, the Sun
was weaker and the Earth
received 6% less
insolation.
• Also, greenhouse gases
(CO² and methane) were
insufficient to hold back
the bitter cold of space.
• Ice sheets 1km thick
engulfed the world
from the poles.
• This would have
increased the world’s
albedo affect reducing
temps to about –50ºC.
• One theory that has
been put forward to
explain the Ice Ages
is: Milankovich cycles
• It considers both
changes in the tilt of
the Earth’s axis and
variations in its orbit
around the Sun.
• The Earth tilts on its axis,
if it didn’t we wouldn’t
have seasons.
• The tilt averages about
23.5 degrees, but it is not
constant.
• The Earth wobbles or
precesses about its axis
over 23/26,000 years.
• This causes the tilt to
change between 22 and
25 degrees over 41,000
years.
Milankovich cycles – variations in
shape of Earth’s orbit around Sun
Milankovich cycles – changes in the
tilt of the Earth’s axis
During the Ice Ages
water was locked up
in glaciers, polar sea
ice and ice sheets.
Sea levels dropped
(120m) allowing
migration of people
and animals.
In the UK, temps were
reduced by 15/20ºC.
Just 600 generations ago the
northern hemisphere was in
full glaciation with a third of
all land covered by ice and
5% of the world’s oceans
frozen.
The switch from cold to warm
and vice versa can occur
rapidly – within decades –
and the disruption of ocean
currents can have serious and
far-reaching consequences
for climatic change.
• Tors
• The switch from cold to
warm and vice versa can
Charles Dickens, White
Christmases, and the Little Ice Age
Why did CD always
write about snowy
winters?
Why do we have an
expectation, or wish
for, an old fashioned
‘white Christmas’?
Where did the Vikings
go?
Little Ice Age
1450 (possibly 1200) –1850
(and start of 20th C.)
glaciers advanced.
Engulfing alpine villages
Fishing industries disrupted
Eskimos paddled to Scotland
Thriving Viking community
in Greenland was cut off
and never heard from
again.
Annual mean temps in
England (late 17th C.)
were almost 1 degree
lower than 1920-60.
NB: Medieval Warm
Period – 1000 –
1300AD.
A very British Ice Age
It is said that GW could
delay an Ice Age but it
could also bring its return
(at least as far as the UK
and Northern Europe are
concerned).
Why is it possible to have
tropical palms in western
Ireland and SW England?
= GULF STREAM
One of the ways to weaken or
shut down the gulf stream
would be to inject large
quantities of cold, fresh
water into the N Atlantic.
If GH gas emissions double
over the next 70 years then
the warming currents could
weaken by 30%.
Under a ‘business as usual’
scenario, GH gas emissions
will quadruple by 2100.
This will lead to a complete
shutdown by the middle of
the next century.
Great Ocean Conveyor Belt
Out of the frying pan into the fridge
“The legacy of warming
today may be freezing
tomorrow”.
Influx of cold fresh water
has a lower density,
remaining on the surface,
cooling the air above, and
creating low pressure
systems (+ve feedback).
Simply a matter of time.
• Huge migrations south as
Europe, N. American, Russia
and E. Asia become
inhospitable.
• This will inevitably lead to
wars over resources and living
space.
• The climate of Ice Age earth is
not suitable for sustaining a
population of 8-10 bn.
• Civil strife, famine will
severely cull the human pop’n.
• We’ll survive but it is likely to
be a shadow of its former self.
The Enemy Within
Super-Eruptions, Giant Tsunamis,
and the Coming Great Quake
Hell on Earth
Imagine the worst possible
vision of hell.
• Stench of sulphur
• World of darkness
• Ash falls like snow, clogging
eyes, nose, and ears as
swiftly as you can remove it
• Choke and retch as you try
and gouge out the ashy, gritty
slime
• Swept off your feet and
pounded by mud
• Slowly roasting in nature’s
own oven
• Half a bn people in the
danger zones don’t need
to use their imagination.
• What happens if enacted
1,500km from the
eruption?
• Fortunately these are far
from common; perhaps 2
in every hundred
millennia.
• But, they could occur
anywhere, anytime and
would affect everyone.
Super-Eruptions
Super-Eruption =
•
standard volcanic blast x 1000
(Mt. St. Helens, 1980 = VEI 5)
This would be described using the
VEI (Volcanic Explosivity
Index), similar to the Richter
scale as it’s logarithmic.
VEI 5
x10 than a 4
VEI 6
x100
VEI 7
x1000
•
•
It is quite worrying that these
seem to occur every 650,000 years
or so. The last one was about
650,000 years ago in Yellowstone
in Wyoming, USA.
73, 500 years ago, well within the
time span of modern humanity –
‘perhaps the greatest volcanic
explosion ever’ that took place at
Toba in northern Sumatra. It
qualified as a VEI 8!
It tore a hole in the ground one
hundred kilometres across and
sent an estimated 3,000 cubic
kilometres of debris into the
atmosphere, enough to cover
virtually the whole of India with a
layer of ash one metre thick
•
•
Ice cores detect that a volcanic
winter of perhaps six years
followed with up to 5,000 million
tonnes of sulphuric acid aerosols
in the air, enough to cut the
amount of sunlight reaching the
surface by 90 per cent.
An ice age followed, perhaps
triggered by the mammoth
eruption. So many humans died
world wide that humanity went
through a "population bottleneck"
that almost sent us the way of the
dinosaurs. It is estimated through
study of mitochondria that we are
all to similar (we come from the
same same gene pool) and that
population numbers were down to
a few thousand.
• Where?
• Most likely in restless
calderas (craters) such as
Yellowstone or Toba.
• But large earthquakes and
huge swelling would last
decades or even centuries,
and neither show such
activity.
A watery grave
• The Mt. St. Helens
landslide that initiated
its 1980 volcano was
tiny with a volume of
less than a cubic km
compared to 1,000 on
Hawaiian Islands.
• So what?
• A rock falling off a
volcano, however big,
couldn’t have a global
impact?
• Well, what happens if
that collapse occurs
into the ocean?
Big Waves
• Giant tsunamis up to 100s
of metres high.
• These have been responsible
for coral reef debris over
300m above sea level.
• Unlike wind-driven waves
which have wavelengths of
a few 10’s of metres, these
would be km’s long.
• An approaching giant
tsunami would keep coming
for about 10-15 mins before
taking the same time to
withdraw.
•
•
•
•
In 1949 a gigantic landslide on
the western flank of the Cumbre
Vieja volcano on La Palma
(Canary Islands) dropped 4m
overnight.
When the Cumbre Vieja
collapses into the sea, the
displacement of water will batter
the eastern cities of US by
tsunamis up to 50m high.
9 hours to hit US coastlines
would be insufficient to initiate
any forward planning,
evacuation etc.
Millions would be crushed,
insurance companies and
economy would totally collapse.
• Many links with increased incidences of
past volcano collapse with periods of
eustatic sea level changes.
• More rain, higher sea level, warmer planet
• Move uphill, inland, or at least invest in a
good wet suit.
The city waiting to die
• What do you do in an
earthquake?
• Panic, freeze, run outside ‘get the hell out of there’,
well that’s what 70% of the
people in the Loma Prieta
(California, 1989) earthquake
did.
• Only 13% sought immediate
protection.
• “Buildings kill people, not
earthquakes” – 400,000
poorly constructed buildings
succumbed to severe ground
shaking during the 2001
Gujarat earthquake in India.
• If the unfortunate event
occurred in Mexico City,
consequences would be
devastating but the global
impact would be minimal.
• But if ground zero was
Tokyo then things would
be different.
• The greatest conurbation
on the planet with a
projected excess of 29m
people by 2015.
There goes the neighbourhood
• An earthquake in the TokyoYokohama region similar in
intensity (8.3 on the Richter
Scale) to that which struck in
1923 is thought to be only
decades away. The next great
Tokyo earthquake is expected
to cause damage totalling at
least 7 trillion US$ (35x Kobe)
and may trigger a global
economic collapse, as 70% of
the world’s largest companies
have their HQ in Tokyo.
• The 1995 Kobe earthquake is
just a mini version of the
‘Great Quake’ that could occur.
• Prediction is difficult if nigh
impossible.
• Water levels in wells, gas
emissions (radon), even
animal behaviour.
• How do you decide,
whether, for example, a pig
is behaving strangely?
• Contingency plans,
evacuation would be far
from effective
• The frightening consensus
amongst seismologists
predict 30 – at best.
The Threat from Space
Asteroids and Comet Impacts
• In 1993 Eugene Shoemaker and his team spotted 21
huge chunks of rock from a comet were separated
due to the strength of Jupiter’s gravitational field.
• Instead of orbiting the Sun this comet had been
captured by Jupiter’s gravity.
• On 16th July 1994, the first fragment of Comet
Shoemaker-Levy struck Jupiter. Two days later a
rock fragment 4km wide and rather unromantically
named fragment G smashed into the planet with the
same force as 8 bn Hiroshima-sized atomic bombs.
• This left a scar bigger than Earth.
• So what happens if this has occurred on Earth?
• The chance of being killed
during an asteroid or comet
walloping is 750 times more
likely than winning the UK
lottery.
• Worst scenario is a hoard of
comets being dislodged from
their normal orbits to fly
toward earth, so many that we
would have no ability to ward
them off
• The chance of the Earth being
struck in the future is 100%,
but they are less frequent
nowadays.
• The impact all depends on the
size, speed and where it hits.
The cosmic sandstorm
•
•
•
•
•
The entire solar system teems
with debris from pea sized to the
1,000km minor planet Ceres.
The ones of significant sizes to
us are ones that exceed 1km.
These are mainly asteroids.
There are between 500 and
1,100 ECA’s (Earth Crossing
Asteroids) over 1km. 320 now
have identified orbits.
Collision with 1-1.5km ECA
would kill quarter of the world’s
population.
An asteroid large enough to
destroy London, NYC or Paris
strikes the planet a few times a
century.
Barringer (Meteor) Crater
When world’s collide
• Comets are masses of
rock and ice up to 100km
across. While asteroids
follow circular paths,
comets take elliptical.
• The apparition of a
comet’s tail as it enters
the solar system has long
been regarded as a portent
of doom and disaster.
• They travel at 100x speed
of the concorde, 3x that
of ECA’s – more
energetic and destructive.
• Also, their orbital
parameters are poorly
known (except Halley’s).
• Comets follow parabolic
orbits.
• We may just get 6 months
warning of a future comet
impact.
• Ancient impacts have
wiped out 90% of all life.
‘Disasterman’
• This is not aimed to make me a ‘harbinger of doom’.
• Do not leave with a feeling of hopelessness for the future
• Yes, the earth is geologically very dangerous, and the
more geologists that study our planet the more potentially
serious the threat seems to be.
• We are, however, learning all the time; collecting data
that can be used to counter or minimise the impact of the
next natural disaster.
• In the future it will probably be possible to predict
earthquakes with some accuracy and precision,
• Within a century no volcano or swell of magma will
escape our satellite warning system.
• At the very least we will be much better prepared than our
distant ancestors