Arctic sea ice melt futures
Arctic Sea Ice measurements are still being reported by the National Snow and Ice Data Center but are not much noted in the national press.
Arctic sea ice extent in December 2011 averaged 12.38 million square kilometers (4.78 million square miles). This is the third lowest December ice extent in the 1979 to 2011 satellite data record, 970,000 square kilometers (375,000 square miles) below the 1979 to 2000 average extent.
Animated map is here.
Previous Angry Bear posts on sea ice are here, here, and here.
below are three arctic earth projections which show methane levels in the atmosphere in the northern hemisphere, from november 2002, 2010, and 2011….the colors are concentrations of methane as shown by the bar at the bottom of each map, with blue being the least and yellow and red showing higher amounts…you can see that there has been a dramatic increase in atmospheric methane in just the past year…
3 or 4 weeks ago there were a few articles about russian scientists who had discovered vast plumes of methane bubbling to the surface of the arctic ocean off the coast of siberia; small columns of methane bubbles had been observed previously, but these were described as “powerful and impressive seeping structures more than 1,000 metres in diameter” and that they had observed hundreds of such plumes in a relatively small area, suggesting that there were likely thousands of them off the siberian coast…
what appears to have happened over the past year is that the arctic ocean off the siberian coast has become warm enough to start a significant melting of the methane hydrates on the seabed, and they’ve begun entering the atmosphere at an increasing rate; methane is known to be a potent greenhouse gas, considered 25 times as potent a heat-trapping gas as CO2 over a 100 year time horizon, but 72 times as potent over 20 years…so dont buy no floridda or manhattan real estate…
not to worry. it’s going to be Florida everywhere soon.
The concern regarding methane releases are overblown, and are a distraction. Methane rapidly degrades within decades … but it degrades into CO2, so it is CO2 in another form. There are also time constants of clathrates involved, and the Arctic clathrates remain well insulated due to poor ocean mixing. See http://www.realclimate.org/index.php/archives/2005/12/methane-hydrates-and-global-warming/ and http://www.realclimate.org/index.php/archives/2010/03/arctic-methane-on-the-move/ and http://www.realclimate.org/index.php/archives/2012/01/an-arctic-methane-worst-case-scenario/ and http://www.realclimate.org/index.php/archives/2012/01/an-online-model-of-methane-in-the-atmosphere/