Arctic Floodplains May Play Key Role In Rapid Methane Releases

[hatrack]

Many fear that, in the coming years, large amounts of methane will be released into the atmosphere. Methane is a much stronger greenhouse gas than carbon dioxide and global warming could lead to melting of the arctic tundras, setting free large volumes of methane, scientists have reported at the European Geosciences Union's General Assembly being held in Vienna, Austria. This would in its turn increase global warming.

Methane fluxes from the arctic permafrost areas attract scientific attention because the release of this powerful greenhouse gas may act as a positive feedback to climate warming. Methane release, generally, is enhanced by increasing the metabolic activity of methane bacteria in warmer arctic soils, or by the release of methane from melting permafrost.

However, research in the Northeast Siberian tundra has shown the importance of floodplain hydrology. The floodplains of arctic lowland rivers are major methane sources, where methane fluxes may be 5 times as high as in non-flooded tundra bogs. Moreover, these fluxes are very sensitive to river discharge fluctuations and the incidence of river floods. During a two year field campaign the drier year resulted in a 75% reduction of the methane flux. Currently, both air temperature and river discharges are rising significantly in the arctic.

EDIT

http://www.sciencedaily.com/releases/2006/04/060404200308.htm

[Dr.Phool]

1. I guess I better throw out that fresh pot of chili.

A lot of methane in that stuff!