Methane linked to Seismic Activity in the Arctic
Temperature data are used to calculate methane emission points in the Arctic, pointing at methane hydrates disturbed by seismic activity as the likely source of high methane concentrations in the Arctic.
By Light, M.P.R. and Carana, S., September 27, 2011
Methane concentrations in the Arctic are higher than elsewhere in the world, as shown on the NASA imagebelow.
Series of research flights have, over the past few years, provided a detailed picture of methane in the Arctic atmosphere at different altitudes. In many descents, enhanced methane concentrations were observed near the surface of the Arctic Ocean, sometimes in otherwise pristine air, possibly signifying emission from biogenic sources or from methane hydrates, concludes a study recently published by the Royal Society, as shown on adapted image left.
A Russian-U.S. expedition comprising 28 scientists has, in its research of the Arctic seas, found powerful methane emissions in the northern sector of the Laptev and Bering seas. Expedition Chief Igor Semiletov says that 'methane torches' have been running up from the depth of the ocean with methane emitted into the air. Possibly, methane comes from the depth of the Earth crust, which is a sign of a strong seismic activity in this region, Semiletov said.
The danger of methane releases triggered by seismic activity in the Arctic was described by Carana in Runaway Warming (2011a) and in Runaway Global Warming (2011b) and by Light (2011). The link between earthquake activity along the Arctic Gakkel Ridge with destabilization of the submarine Arctic methane hydrates and the release of giant plumes of methane to the atmosphere was highlighted by Light and Solana (2002).
The images below show how methane emission points can be derived from Arctic temperature peaks.
Figure 1 below shows how methane, emitted from the surface permafrost and submarine Arctic hydrates, is spreading in the stratosphere in the northern Hemisphere in a great circle, around a cold high pressure zone centred on the fringes of Western Europe. Temperature anomalies, caused by the stratospheric dispersion of Arctic methane, originate in the Arctic permafrost and Arctic Ocean areas and are spreading further and further afield as time progresses.
Much, much more at this link: http://knol.google.com/k/sam-carana/methane-linked-to-seismic-activity-in/7y50rvz9924j/85#
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