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The maps above compare the Arctic ice minimum extents from
2012 (top) and 1984 (bottom). In 1984 the sea ice extent was roughly the
average of the minimum from 1979 to 2000, and so was a typical year. The
minimum sea ice extent in 2012 was roughly half of that average.
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Sea ice coverage in 1980 (bottom) and 2012 (top), as
observed by passive microwave sensors on NASA’s Nimbus-7 satellite and by the
Special Sensor Microwave Imager/Sounder (SSMIS) from the Defense Meteorological
Satellite Program (DMSP). Multi-year ice is shown in bright white, while
average sea ice cover is shown in light blue to milky white. The data shows the
ice cover for the period of 1 November through 31 January in their respective
years.
Arctic ice melt could cost an extra $60 trillion, say
researchers
Methane gas released from the melting Arctic ice could
accelerate global warming and tack on an extra $60 trillion to the cost the
world is expected to incur from climate change.
By Elizabeth Barber, Contributor / July 24, 2013 / http://www.csmonitor.com/Science/2013/0724/Arctic-ice-melt-could-cost-an-extra-60-trillion-say-researchers
The oil and gas industries have in recent years forecasted
profits from easier access to resource fields in the melting Arctic. Northern
states have welcomed the trade routes that are emerging from the thick ice’s
melt. But those possible boons pale in comparison to the costs that methane
emissions from the melting ice will have on the global economy, scientists have
found.
The price tag? $60 trillion – or about the size of the
entire global economy in 2012 – according to new research that modeled the
economic toll that methane gases seeping out of the Arctic will take on the
world.
“Its not just bad news for the polar bear,” said Gail
Whiteman, a researcher at Erasmus University in the Netherlands and a co-author
on the paper, published in Nature. “It’s a global economic time bomb."
The Arctic is thought to contain about 30 percent of the
world's undiscovered gas, as well as about 13 percent of its untapped oil.
Those economic opportunities have provided major incentives for investment in
Arctic oil and gas fields. Lloyd's of London, an insurance market, has
projected that investment in the region could reach US$100 billion within ten
years.
At the same time, thawing ice has also cleared a route for
vessels there during the summer. Arctic shipping is expected to see about 40
million tons a year in 2050.
But those projected figures do not present a full picture of
the economic effects of melting in the Arctic, the authors said.
The Arctic ice stores roughly 50 billion tons of methane, a
concentrated gas some 20 times more powerful than carbon dioxide. Over the past
few years, scientists have observed the gas pluming from the region’s thawing
ice. That raised the question: even as profits are hauled in from shipping and
drilling in the Arctic, could that methane gas be waiting to undo all those
gains? Could the toll of that released gains far outweigh the rewards of melting
Arctic’s ice?
Researchers used what is called the PAGE09 model to assess a
broad range of risks arising from methane gas release. Their work is built on
the 2006 Stern Review on the Economics of Climate Change’s model, which judged
the economic effect of extra greenhouse-gas emissions on such factors as sea
level rise, temperature, and extreme weather risk. That model found that, as a
result of global warming, the world would incur a total cost of $450 trillion
by the end of the century.
But seven years ago there was too little research on methane
gas in the Arctic to include in the model its influence on the global economy,
Dr. Whiteman said. So this time, scientists modeled a ten-year release of the
50-billion-ton methane bubble between 2015 and 2025 and showed the effects of
that decade-long burst until 2200. The model was based on the current rate of
greenhouse emissions.
The team found that methane release from just the melting
permafrost beneath the East Siberian Sea would accelerate the rise in
temperatures to 3.6 degrees Fahrenheit above preindustrial levels to 2030. That
increase in temperatures would cost the world some $60 trillion – a sum almost
as large as the size of the entire global economy last year, totaled at about
$70 trillion. It is also an added cost of about 15 percent to the already $450
million in damages that the Stern model had found in 2006.
“Without question there are some gains for some industries
and some countries – but that doesn’t into account that climate change’s
negative impact throughout the entire world,” said Whiteman.
That $60 trillion sum is a mean number based on the
estimated – but still unknown – amount of methane in the Arctic. That puts the
lower and upper boundaries of the total cost at $10 trillion and $220 trillion.
The model was also based on a ten-year burst of methane beginning in 2015, but
when and over what length of time methane seepage might occur is still unknown.
The developing world will be saddled with about 80 percent
of the cost: Countries there are poorly insulated from the toll that climate
change can take on public health, agriculture, and infrastructure would end up
footing the bill, Whiteman said.
“Those places are climate vulnerable and will pick up the
price-tag,” she said.
Researchers also modeled the damage at a lower rate of
greenhouse gas emissions, with a 50 percent chance of keeping global
temperatures below the expected 3.6-degree increase from preindustrial levels.
Under that model, the temperature increase and its attached price tag would
come at 2040, buying five years time.
“It's a when not an if,” said Peter Wadhams, a professor of
ocean physics at the University of Cambridge and a co-author on the study,
noting that preventing methane leakage would mean lowering CO2 levels to a
point that restore the freeze the melted ice again. “We don’t have a good way
of stopping this process. All we can do is find ways to minimize the impact on
human life.”
Still, the situation is not hopeless, the authors said.
Abating global warming buys time for intensive geo-engineering research into
strategies for dealing with methane release, noted Dr. Wadhams.
"It's too expensibe not to do anything about global
warming," he said.
In collaboration with other researchers, the team is next
planning to model the broader effects of melting in the entire Arctic. Those
effects include ocean acidification, as well as altered ocean and atmospheric
circulation. The future model will also deepen an understanding of how methane
gas will affect the world, pinpointing the regions and countries that will bear
the brunt of its costs and the specific tolls that it will take on those
economies.
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The melting north.
The Arctic is warming twice as fast as the rest of the
planet, says James Astill. The retreating ice offers access to precious
minerals and new sea lanes—but also carries grave dangers
Jun 16th 2012 |From the print edition / http://www.economist.com/node/21556798
STANDING ON THE Greenland ice cap, it is obvious why
restless modern man so reveres wild places. Everywhere you look, ice draws the
eye, squeezed and chiselled by a unique coincidence of forces. Gormenghastian
ice ridges, silver and lapis blue, ice mounds and other frozen contortions are
minutely observable in the clear Arctic air. The great glaciers impose order on
the icy sprawl, flowing down to a semi-frozen sea.
The ice cap is still, frozen in perturbation. There is not a
breath of wind, no engine's sound, no bird's cry, no hubbub at all. Instead of
noise, there is its absence. You feel it as a pressure behind the temples and,
if you listen hard, as a phantom roar. For generations of frosty-whiskered
European explorers, and still today, the ice sheet is synonymous with the power
of nature.
The Arctic is one of the world's least explored and last
wild places. Even the names of its seas and rivers are unfamiliar, though many
are vast. Siberia's Yenisey and Lena each carries more water to the sea than
the Mississippi or the Nile. Greenland, the world's biggest island, is six
times the size of Germany. Yet it has a population of just 57,000, mostly Inuit
scattered in tiny coastal settlements. In the whole of the Arctic—roughly
defined as the Arctic Circle and a narrow margin to the south (see map)—there
are barely 4m people, around half of whom live in a few cheerless post-Soviet
cities such as Murmansk and Magadan. In most of the rest, including much of
Siberia, northern Alaska, northern Canada, Greenland and northern Scandinavia,
there is hardly anyone. Yet the region is anything but inviolate.
Fast forward
A heat map of the world, colour-coded for temperature
change, shows the Arctic in sizzling maroon. Since 1951 it has warmed roughly
twice as much as the global average. In that period the temperature in
Greenland has gone up by 1.5°C, compared with around 0.7°C globally. This
disparity is
expected to continue. A 2°C increase in global temperatures—which
appears inevitable as greenhouse-gas emissions soar—would mean Arctic warming
of 3-6°C .
Almost all Arctic glaciers have receded. The area of Arctic
land covered by snow in early summer has shrunk by almost a fifth since 1966.
But it is the Arctic Ocean that is most changed. In the 1970s, 80s and 90s the
minimum extent of polar pack ice fell by around 8% per decade. Then, in 2007,
the sea ice crashed, melting to a summer minimum of 4.3m sq km (1.7m square
miles), close to half the average for the 1960s and 24% below the previous
minimum, set in 2005. This left the north-west passage, a sea lane through
Canada's 36,000-island Arctic Archipelago, ice-free for the first time in
memory.
Scientists, scrambling to explain this, found that in 2007
every natural variation, including warm weather, clear skies and warm currents,
had lined up to reinforce the seasonal melt. But last year there was no such
remarkable coincidence: it was as normal as the Arctic gets these days. And the
sea ice still shrank to almost the same extent.
There is no serious doubt about the basic cause of the
warming. It is, in the Arctic as everywhere, the result of an increase in
heat-trapping atmospheric gases, mainly carbon dioxide released when fossil
fuels are burned. Because the atmosphere is shedding less solar heat, it is
warming—a physical effect predicted back in 1896 by Svante Arrhenius, a Swedish
scientist. But why is the Arctic warming faster than other places?
Consider, first, how very sensitive to temperature change
the Arctic is because of where it is. In both hemispheres the climate system
shifts heat from the steamy equator to the frozen pole. But in the north the
exchange is much more efficient. This is partly because of the lofty mountain
ranges of Europe, Asia and America that help mix warm and cold fronts, much as
boulders churn water in a stream. Antarctica, surrounded by the vast southern
seas, is subject to much less atmospheric mixing.
The land masses that encircle the Arctic also prevent the
polar oceans revolving around it as they do around Antarctica. Instead they
surge, north-south, between the Arctic land masses in a gigantic exchange of
cold and warm water: the Pacific pours through the Bering Strait, between
Siberia and Alaska, and the Atlantic through the Fram Strait, between Greenland
and Norway's Svalbard archipelago.
That keeps the average annual temperature for the high
Arctic (the northernmost fringes of land and the sea beyond) at a relatively
sultry -15°C ;
much of the rest is close to melting-point for much of the year. Even modest
warming can therefore have a dramatic effect on the region's ecosystems. The
Antarctic is also warming, but with an average annual temperature of -57°C it will take more than
a few hot summers for this to become obvious.
The albedo effect
The efficient north-south mixing of air may also play a part
in the Arctic's amplified warming. The winds that rush northwards carry
pollutants, including soot from European and Asian smokestacks, which has a
powerful warming effect over snow. In recent decades there has also been a rise
in levels of mercury, a by-product of burning coal, in the tissues of beluga
whales, walruses and polar bears, all of which the Inuit eat. This is another
reason why the Arctic is not virgin.
But the main reason for Arctic amplification is the warming
effect of replacing light-coloured snow and ice with darker-coloured land or
water. Because dark surfaces absorb more heat than light ones, this causes
local warming, which melts more snow and ice, revealing more dark land or
water, and so on. Known as the albedo effect, this turns out to be a more powerful
positive feedback than most researchers had expected. Most climate models
predicted that the Arctic Ocean could be ice-free in summer by the end of this
century; an analysis published in 2009 in Geophysical Research Letters suggested
it might happen as early as 2037. Some now think it will be sooner.
It is hard to exaggerate how dramatic this is. Perhaps not
since the felling of America's vast forests in the 19th century, or possibly
since the razing of China's and western Europe's great forests a thousand years
before that, has the world seen such a spectacular environmental change. The
consequences for Arctic ecosystems will be swingeing.
As their ancient ice buffers vanish, Arctic coastlines are
eroding; parts of Alaska are receding at 14 metres (45 feet ) a year. Niche
habitats, such as meltwater pools on multi-year ice, are dwindling. Some highly
specialised Arctic species will probably become extinct as their habitats
shrink and southern interlopers rush in. Others will thrive. The early signs of
this biological reshuffle are already evident. High-Arctic species, including
the polar bear, are struggling. Species new to the region, such as mackerel and
Atlantic cod, are coming up in Arctic trawler nets. Yet the shock waves of
Arctic change will be felt much more widely.
Melting sea ice will not affect global sea levels, because
floating ice displaces its own mass in seawater. But melting glaciers will, and
the Arctic's are shedding ice at a great rate. Greenland's ice cap is losing an
estimated 200 gigatonnes of ice a year, enough to supply a billion people with
water. The Arctic's smaller ice caps and glaciers together are losing a similar
amount. Before this became clear, the Intergovernmental Panel on Climate Change
(IPCC) had predicted a sea-level rise of up to 59cm during this century. Given
what is happening up north, many now think this too modest.
A wilder fear is that a deluge of Arctic meltwater could
disrupt the mighty “overturning circulation” of the global oceans, the exchange
of warm tropical and cold polar water. It has happened before, at least seven
times in the past 60,000 years, and needs watching. But recent evidence
suggests that such a calamity is not imminent. Another concern, that thawing
Arctic permafrost could release vast quantities of carbon dioxide and methane,
looms larger. That, too, has happened before, around 55m years ago, leading to
a global temperature increase of 5°C
in a few thousand years.
Such risks are hard to pin down, and possibly small. Many elements
of the change in the Arctic, including the rates of snow melt and glacier
retreat, are still within the range of historical variations. Yet the fact that
the change is man-made is unprecedented, which introduces huge uncertainty
about how far and fast it will proceed. For those minded to ignore the risks,
it is worth noting that even the more extreme predictions of Arctic warming
have been outpaced by what has happened in reality.
Riches of the north
In the long run the unfrozen north could cause devastation.
But, paradoxically, in the meantime no Arctic species will profit from it as
much as the one causing it: humans. Disappearing sea ice may spell the end of
the last Eskimo cultures, but hardly anyone lives in an igloo these days
anyway. And the great melt is going to make a lot of people rich.
As the frozen tundra retreats northwards, large areas of the
Arctic will become suitable for agriculture. An increasingly early Arctic
spring could increase plant growth by up to 25%. That would allow Greenlanders
to grow more than the paltry 100 tonnes of potatoes they manage now. And much
more valuable materials will become increasingly accessible. The Arctic is
already a big source of minerals, including zinc in Alaska, gold in Canada,
iron in Sweden and nickel in Russia, and there is plenty more to mine.
The Arctic also has oil and gas, probably lots. Exploration
licences are now being issued across the region, in the United States, Canada,
Greenland, Norway and Russia. On April 18th ExxonMobil finalised the terms of a
deal with Russia's Rosneft to invest up to $500 billion in developing offshore
reserves, including in Russia's Arctic Kara sea. Oil companies do not like to
talk about it, but this points to another positive feedback from the melt.
Climate change caused by burning fossil fuels will allow more Arctic
hydrocarbons to be extracted and burned.
These new Arctic industries will not emerge overnight. There
is still plenty of sea ice to make the north exceptionally tough and expensive
to work in; 24-hour-a-day winter darkness and Arctic cyclones make it tougher
still. Most of the current exploration is unlikely to lead to hydrocarbon
production for a decade at least. But in time it will happen. The prize is
huge, and oil companies and Arctic governments are determined to claim it.
Shortly before the ExxonMobil-Rosneft deal was announced, Vladimir Putin,
Russia's president, announced plans to make it much more attractive for
foreigners to invest in Russian offshore energy production. “Offshore fields,
especially in the Arctic, are without any exaggeration our strategic reserve
for the 21st century,” he said.
For half the 20th century the Arctic, as the shortest route
between Russia and America, was the likeliest theatre for a nuclear war, and
some see potential for fresh conflict in its opening. Russia and Canada, the
two biggest Arctic countries by area, have encouraged this fear: the Arctic
stirs fierce nationalist sentiment in both. With a new regard to their northern
areas, some of the eight Arctic countries are, in a modest way, remilitarising
them. Norway shifted its military command centre to the Arctic town of Reitan
in 2009. Russia is replacing and upgrading its six nuclear icebreakers, a piece
of civilian infrastructure with implications for security too. Yet this special
report will suggest that warnings about Arctic conflict are, like the climate,
overcooked.
The Arctic is no terra nullius. Unlike Antarctica, which is
governed by an international treaty, most of it is demarcated. Of half a dozen
territorial disputes in the region, the biggest is probably between the United
States and Canada, over the status of the north-west passage. Those two
countries will not go to war. And the majority of Arctic countries are members
of NATO.
Yet the melting Arctic will have geostrategic consequences
beyond helping a bunch of resource-fattened countries to get fatter. An obvious
one is the potentially disruptive effect of new trade routes. Sailing along the
coast of Siberia by the north-east passage, or Northern Sea Route (NSR), as
Russians and mariners call it, cuts the distance between western Europe and
east Asia by roughly a third. The passage is now open for four or five months a
year and is getting more traffic. In 2010 only four ships used the NSR; last
year 34 did, in both directions, including tankers, refrigerated vessels
carrying fish and even a cruise liner.
Asia's big exporters, China, Japan and South Korea, are
already investing in ice-capable vessels, or planning to do so. For Russia,
which has big plans to develop the sea lane with trans-shipment hubs and other
infrastructure, this is a double boon. It will help it get Arctic resources to
market faster and also, as the NSR becomes increasingly viable, diversify its
hydrocarbon-addicted economy.
There are risks in this, of dispute if not war, which will
require management. What is good for Russia may be bad for Egypt, which last
year earned over $5 billion in revenues from the Suez Canal, an alternative
east-west shipping route. So it is good that the regional club, the Arctic
Council, is showing promise. Under Scandinavian direction for the past
half-decade, it has elicited an impressive amount of Arctic co-operation,
including on scientific research, mapping and resource development.
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