In what sounds like a scene from a Hollywood disaster film, scientists looked over the side of the Russian research vessel Yacob Smirnisky to view the ocean foaming as huge ancient deposits of methane, a greenhouse gas 20 times more potent than carbon dioxide, began to thaw and bubble to the surface. The alarming reports of what the International Siberian Shelf Study 2008 have been witnessing over the last few days were sensationally revealed by Britain's Independent Newspaper two days ago (23^rd September 2008). As the newspaper reports this is the first evidence that millions of tons of methane are beginning to be released into the atmosphere from beneath the Arctic Ocean.

The intense concentrations of the greenhouse gas, some up to 100 times background levels, were discovered in the East Siberian Sea and the Laptev Sea, an area some tens of thousands of square miles in the Siberian continental shelf. The Independent published extracts from emails sent from one of the lead researchers aboard the Yacob Smirnisky, Orjan Gustafsson of Stockholm University:

"We had a hectic finishing of the sampling programme yesterday and this past night," said Dr Gustafsson. "An extensive area of intense methane release was found. At earlier sites we had found elevated levels of dissolved methane. Yesterday, for the first time, we documented a field where the release was so intense that the methane did not have time to dissolve into the seawater but was rising as methane bubbles to the sea surface. These 'methane chimneys' were documented on echo sounder and with seismic [instruments]."

Massive stores of methane, which formed before the last ice age, are locked away beneath the permafrost of the northern hemisphere. Produced naturally by the decay of water-logged vegetation, over millennia the methane deposits have accumulated beneath the land and ocean, removing huge quantities of carbon from the atmosphere. Permafrost at the sea floor had acted like a lid to prevent the huge methane deposits, from escaping. It's thought that this new phenomenon is related to the rapid warming that the Arctic region has experienced in recent years.

As Gustafsson wrote:

"The conventional thought has been that the permafrost 'lid' on the sub-sea sediments on the Siberian shelf should cap and hold the massive reservoirs of shallow methane deposits in place... We have found elevated levels of methane above the water surface and even more in the water just below. It is obvious that the source is the seabed." 

Methane is a short-lived greenhouse gas, remaining in the atmosphere for about 12 years compared to the 100 years of carbon dioxide. However, the danger comes from the fact that methane is about 20 times more potent than carbon dioxide at trapping solar radiation. Scientists have long warned that the release of these massive deposits of methane could create a huge "positive feedback mechanism." The methane released from beneath the permafrost could increase temperatures, melting the permafrost faster, releasing even more methane, and so on. It is feared that such a scenario would accelerate Global Warming to the point where nothing mankind could do would reverse the problem.

Scientists believe that similar releases of methane in the past, so called "methane burps", have caused rapid and severe increases in global temperatures, dramatic climate change and mass extinctions. Methane levels in the atmosphere had risen steadily since the industrial revolution only to level out in recent times. Then in 2007 a rise in global methane levels was recorded. At the time researchers were unsure if this was the beginning of a trend.

With these latest revelations, it seems that another rise in global methane levels is set to be recorded this year. The extreme loss of Arctic sea ice seen in recent years could aggravate the problem further as the darker seas warm faster than the ice, which had reflected vast amounts of solar radiation back into space. The question is this; how will the world respond to what is undoubtedly a disaster in progress? At a time when our attention is focused on the turbulence in the world's economic markets will we continue to ignore the warnings of science? "Nobody knows how many more such areas exist on the extensive East Siberian continental shelves," according to Dr Gustafsson.

The findings of the International Siberian Shelf Study 2008 will be published in the American Geophysical Union. The team have been recording their course on Google Maps.

Further Reading:

• Has Earth Passed the Tipping Point?
• Lack of Arctic Ice Closing NORAD Radar Stations in Alaska
• Is the Arctic Heatwave a Sign the Earth has gone Past the Climate Change Tipping Point?
• Feedback Loops: Melting Permafrost