11 January 2010

methane is leaking from the Arctic


This story is really quite worrying. According to Professor Igor Semiletov, who leads the International Siberian Shelf Study (ISSS) at the University of Alaska, methane leakage from the Arctic seabed appears to have dramatically increased.

Semiletov's team told the BBC they had recorded methane levels in the atmosphere around the region 100 times higher than normal background levels, and in some cases 1,000 times higher. Methane is 23 times more potent than CO2 as a greenhouse gas in the atmosphere, but 33 times if you include its indirect effect on tropospheric ozone and stratospheric water vapour. The Arctic methane was formerly trapped in water ice (methane hydrates), but global warming, which is far stronger at the poles than elsewhere, is causing it to melt.

There is thought to be up to twice as much carbon trapped in the form of methane hydrates than there is in the atmosphere. The great fear is that billions of tonnes of it will be released suddenly as melting occurs and that this will tip the earth into runaway climate change. This is what many scientists now think happened during the Permian-Triassic extinction when more than 95% of all species on the planet were wiped out. Read the full story here on the BBC website: http://news.bbc.co.uk/1/hi/sci/tech/8437703.stm