guardian.co.uk, Tuesday 10 March 2009 18.26 GMT
Even modest amounts of global warming could trigger a carbon "time bomb" and release massive amounts of greenhouse gases from frozen Arctic soils, a new study has warned.
Philippe Ciais, a researcher with the Laboratory for Climate Sciences and the Environment in Gif-sur-Yvette, France, told the Copenhagen Climate Congress that billions of tonnes of carbon dioxide and methane could be freed by just a 2C average rise.
He said such a release of greenhouse gases could trigger an "explosive" reaction in the soil, with bacteria able to start decomposing giant stocks of frozen carbon. "You can call it a bacterial heat production effect if you are a pretentious scientist, or you can call it composting," he said.
Using computer models and measurements from Siberia, Ciais and his colleagues predicted a fifth of the carbon could be released by 2200, once soil temperatures reached about 8C higher than today's levels. A global average increase in air temperatures of 2C would mean significantly higher temperatures in the Arctic, and Ciais warned that a few unusually hot years could see soil temperatures reach the 8C threshhold.
He called for a global observation network to monitor permafrost, and said it was a "scandal" that there are only about 20 people measuring it worldwide.
http://www.guardian.co.uk/environment/2009/mar/10/climate-change-copenhagen
Even modest amounts of global warming could trigger a carbon "time bomb" and release massive amounts of greenhouse gases from frozen Arctic soils, a new study has warned.
Philippe Ciais, a researcher with the Laboratory for Climate Sciences and the Environment in Gif-sur-Yvette, France, told the Copenhagen Climate Congress that billions of tonnes of carbon dioxide and methane could be freed by just a 2C average rise.
He said such a release of greenhouse gases could trigger an "explosive" reaction in the soil, with bacteria able to start decomposing giant stocks of frozen carbon. "You can call it a bacterial heat production effect if you are a pretentious scientist, or you can call it composting," he said.
Using computer models and measurements from Siberia, Ciais and his colleagues predicted a fifth of the carbon could be released by 2200, once soil temperatures reached about 8C higher than today's levels. A global average increase in air temperatures of 2C would mean significantly higher temperatures in the Arctic, and Ciais warned that a few unusually hot years could see soil temperatures reach the 8C threshhold.
He called for a global observation network to monitor permafrost, and said it was a "scandal" that there are only about 20 people measuring it worldwide.
http://www.guardian.co.uk/environment/2009/mar/10/climate-change-copenhagen
