Permafrost thaw increases Arctic methane emissions by a third
Their study, published in Science, looked at atmospheric concentrations
of methane from the biggest source of the gas: wetlands such as paddy
fields, marshes and bogs. It found that the amount emitted from Arctic
permafrost has risen by 31 per cent, or an extra one million tonnes a
year between 2003 and 2007 as a result of warmer temperatures at the poles.
Methane is a far more potent greenhouse gas than carbon dioxide, trapping about 20 times more heat than an equivalent amount of CO2, but it’s present in the atmosphere in far lower quantities. The frozen Arctic soil is estimated to contain billions of tonnes of methane, and scientists fear that if the region continues to warm at the current rate – twice that of elsewhere on Earth – the increased emissions from thawing permafrost will bring about a ‘positive feedback’ effect that results in runaway climate change.
Paul Palmer from the university’s School of GeoSciences, who worked on the study, said: ‘These findings highlight the compound effect of increasing global warming – higher temperatures lead to faster warming.’
The researchers estimate that between 2003 and 2007, there was a seven per cent rise in methane emissions from the world’s wetlands, due to warming of mid-latitude and Arctic regions, although this increase wasn’t across a long enough period to be called a trend.
March 2010
Methane is a far more potent greenhouse gas than carbon dioxide, trapping about 20 times more heat than an equivalent amount of CO2, but it’s present in the atmosphere in far lower quantities. The frozen Arctic soil is estimated to contain billions of tonnes of methane, and scientists fear that if the region continues to warm at the current rate – twice that of elsewhere on Earth – the increased emissions from thawing permafrost will bring about a ‘positive feedback’ effect that results in runaway climate change.
Paul Palmer from the university’s School of GeoSciences, who worked on the study, said: ‘These findings highlight the compound effect of increasing global warming – higher temperatures lead to faster warming.’
The researchers estimate that between 2003 and 2007, there was a seven per cent rise in methane emissions from the world’s wetlands, due to warming of mid-latitude and Arctic regions, although this increase wasn’t across a long enough period to be called a trend.
March 2010
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