Increasing temperatures in the Arctic
region are reducing sea ice cover and increasing the possibility of
methane leaching from the sea bed
Scientists say that
the release of large amounts of methane from thawing permafrost in
the Arctic could have huge economic impacts for the world.
The researchers estimate that the climate effects of the release
of this gas could cost $60 trillion (£39 trillion), roughly the size
of the global economy in 2012.
The impacts are most likely to be felt in developing countries
they say.
The research has been published in the journal Nature.
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“Start Quote
That's an economic time bomb that at
this stage has not been recognised on the world stage”
Prof Gaile Whiteman
Erasmus University
Scientists have had concerns about the
impact of rising temperatures on permafrost for many years. Large
amounts of methane are concentrated in the frozen Arctic tundra but
are also found as semi-solid gas hydrates under the sea.
Price of gas
Previous
work has shown that the diminishing ice cover in the East
Siberian sea is allowing the waters to warm and the methane to leach
out. Scientists have found plumes of the gas up to a kilometre in
diameter rising from these waters.
In this study, the researchers have attempted to put an economic
price on the climate damage that these emissions of methane could
cause. Methane is a powerful greenhouse gas, even though it lasts
less than a decade in the atmosphere.
When Russia planted a flag on the
seabed at the North Pole in 2007 it signalled that exploitation
of the Arctic was in full swing
Using an economic model very similar to the one used by Lord
Stern in his
2006 review of the economics of climate change, the researchers
examined the impact of the release of 50-gigatonnes of methane over
a decade.
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Methane hydrate - 'Fire ice'
- Hydrates, or clathrates, are a frozen mixture of water
and gas, primarily methane
- The methane molecules reside inside a water molecule
lattice
- The methane will ignite in ice form - hence the "fire
ice" moniker
They worked out that this would increase
climate impacts such as flooding, sea level rise, damage to
agriculture and human health to the tune of $60 trillion.
"That's an economic time bomb that at this stage has not been
recognised on the world stage," said Prof Gail Whiteman at Erasmus
University in the Netherlands, and one of authors.
"We think its incredibly important for world leaders to really
discuss what are the implications of this methane release and what
could we indeed do about it to hopefully prevent the whole burst
from happening."
The researchers say their study is in marked contrast to other,
more upbeat
assessments of the economic benefits of warming in the Arctic
region.
It is thought that up to 30% of the world's undiscovered gas and
13% of undiscovered oil lie in the waters. Transport companies are
looking to send increasing numbers of ships through these fast
melting seas. According to Lloyds of London, investment in the
Arctic could reach $100bn within ten years.
Methane belch
But according to the new work, these benefits would be a fraction
of the likely costs of a large scale methane emission. The authors
say a release of methane on this scale could bring forward the date
when global temperatures increase by 2C by between 15 and 35 years.
Continue reading the main story
Faster Antarctic melt
New research suggests that permafrost is also melting in
Antarctica. Scientists have found that ground ice in the McMurdo
Dry Valley Regions has accelerated consistently between 2001 and
2012, rising to about ten times the historical average. The
researchers say that rising temperatures do not account for this
increased melting but to an increase in sunlight caused by
changes in weather patterns.
"We are looking at a big effect," said
Prof Peter Wadhams from the University of Cambridge, "a possibly
catastrophic effect on global climate that's a consequence of this
extremely fast sea ice retreat that's been happening in recent
years."
Some scientists have cautioned that not enough is known about the
likelihood of such a rapid release of methane. Even though it has
been detected for a number of years, it has as yet not been found in
the atmosphere in large amounts.
Prof Wadhams says the evidence is growing.
"We are seeing increasing methane in the atmosphere. When you
look at satellite imagery, for instance the Metop satellite, that's
gone up significantly in the last three years and the place where
the increase is happening most is over the Arctic," he said.
The authors say that the impacts of the extra methane would be
felt most in developing countries which are more vulnerable to
rising waters, flooding and the agricultural and health impacts of
rising temperatures.
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