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.

IntroductionThousands 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 2008-12.

• 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 occur rapidly – within decades – and the disruption of ocean currents can have serious and far-reaching consequences for climatic change.

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 EarthImagine 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 Tokyo-Yokohama 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