Thursday, July 19, 2012
Current Sea Ice
First off, the areal minimum is presently on the way to surpassing the areal minimum of 2007. secondly the Areal maximum during the winter was toward the high part of the range. Thus there is simply a lot less ice out there. Again this conforms to the expected changes.
Way more important, we now have a good number for the decadal decline in the sea ice itself. It is thirteen percent. What we lack is a determination on how it may be calculated and it is also suggestive of misleading ideas. Thirteen percent loss since 1970 means a twenty five percent decadal loss at present which is pretty close to reality for the past decade. An awful lot of old sea ice is now gone and what is left is been ground up a lot slower been located disadvantageously.
The right combination of winds similar to 2007 could largely clear the Arctic now.
As posted in the past, this decline appears due to an increase in warm waters been injected into the Arctic from the Gulf Stream. This same phenomena is also inducing a warmer northern Hemisphere. It is noteworthy that we have a counter trend in the Antarctic. For this reason I look to current flows for decadal climate drivers and millennial climate drivers.
Current State of the Sea Ice Cover
State of the Sea Ice Cover
J. C. Comiso, C. L. Parkinson, T. Markus, D. J. Cavalieri and R. Gersten
The sea ice cover is one of the key components of the climate system. It has been a focus of attention in recent years, largely because of a strong decrease in the Arctic sea ice cover and modeling results that indicate that global warming could be amplified in the region by a factor of about 3 to 5 times on account of ice-albedo feedback. This results from the high reflectivity (albedo) of the sea ice compared to ice-free waters. A satellite-based data record starting in late 1978 shows that indeed rapid changes have been occurring in the Arctic, where the perennial ice cover has been declining at the rate of about 13% per decade and the ice cover as a whole has been declining at the lesser rate of about 5% per decade. In the Antarctic, the trend is opposite to that in the Arctic, with the sea ice cover increasing at about 1 to 2 % per decade. This is despite unusual warming in the Antarctic Peninsula region and declines in the sea ice cover in the Amundsen/Bellingshausen Seas of about 6% per decade. In the Arctic, a slight recovery in the sea ice cover has been observed in 2008 and 2009, following a major decline of the ice in 2007, while in the Antarctic, the sea ice cover was more extensive than normal in 2007, 2008, and 2009. Shown below are up-to-date satellite observations of the sea ice covers of both the Arctic and the Antarctic, along with comparisons with the historical satellite record of more than 30 years. The plots and color coded maps are chosen to provide information about the current state of the sea ice cover and how the most current daily data available compare with the record lows and record highs for the same date during the satellite era