The November update of the Polar Science Center’s PIOMAS sea ice volume tracker shows Arctic sea ice volume remaining in record low territory for the month of October. By month’s end, sea ice volume was still about 1096 cubic kilometers below the previous record low set in 2011.
Volume recovery during the seasonal re-freeze was lower than in 2011. During that year, sea ice volume in fall and winter rebounded to levels near those of the previous year. This year, however, the gap between 2011 and 2012 is much greater.
A number of factors kept Arctic re-freeze lower than in previous years. Sea ice has been pushed so far back that it simply takes longer and longer to recover. Warm water ocean currents are traveling further north, transporting more warm water into the Arctic environment later and later in the year. Atmospheric circulation has also changed. Large blocking patterns dredge warm air up from the south and deposit it in the Arctic. These same blocking patterns dump cold air, which once tended to concentrate in the Arctic, into temperate regions. The result of all this ocean and atmospheric mixing is that the Arctic is much warmer than usual and sea ice recovery mostly lags.
In his Arctic Sea Ice Blog, sea ice blogger Neven has also pointed out that it is likely sea ice is also thinner now than ever before. His rough graph combines PIOMAS volume and NSIDC sea ice area data to provide an estimate for average thickness. This month’s graph shows average ice thickness of less than 1 meter over the entire Arctic lasting through November 5th.
Neven’s previous rough estimates had shown average sea ice thickness did not pass below the one meter threshold at any time since records have been established. This year, average sea ice thickness dropped below 1 meter on October 21rst and has remained at that record low level through to November 5th.
Increasing scientific evidence and consensus points toward massively reduced sea ice area and volume resulting in chaotic and damaging weather patterns. Meteorologists and researchers from climate and weather disciplines have attributed Superstorm Sandy’s size, intensity, and path, to influences that have been made worse and worse by human caused climate change. Furthermore, powerful blocking patterns that result from the deterioration of sea ice have been implicated in wide ranging weather extremes including the current historic drought, powerful heat waves in Europe, Russia, and the US, and extreme rain and storm events across the globe.
In addition, receding sea ice kicks off a number of powerful global warming feedbacks that are likely to amplify human-caused climate change, heating the Earth at a faster rate. Loss of insulating sea ice also puts Greenland and West Antarctica at increasingly severe risk of increased melt. The result, in these cases, is much more rapid sea level rise on top of increasingly powerful storms. We are experiencing only the first outliers of these impacts now. So rapid reduction in greenhouse gas emissions can help to prevent the worst of a large pack of climate troubles now forming.