The state of the Arctic sea ice in late December 2009 remains the 2nd worst of any recorded December. The areal extent of sea ice continues to be well below the climatological average, and as it has for most of 2009, significantly below the negative 2nd standard deviation of the 1979-2000 area. The areal extent of Arctic sea ice continues to be anomalously low, as it has for well over a year now. The Hudson Bay has finally iced over. The late freeze this year was due to anomalously warm waters in the Bay in 2009. The Barents Sea remains relatively ice-free for this time of year. Remember, the Arctic Ocean hasn’t seen sun in a couple of months now.
The state of the Antarctic sea ice in late December 2009 is less disturbing. After reaching a high value of ~19 million sq. km. back in late September, the 2009 melt season exceeded that of the 2008 season. That trend shifted slightly as December drew to a close – the areal extent has increased from the 1979-2000 average to the positive 2nd standard deviation. The exact value of areal extent in 2009 remains below the value measured in 2008 by a small amount. The trend found in December is likely due to this year’s storms: both tracks and intensities vary year to year.
Globally, the extent of sea ice in 2009 continued the trend seen throughout the Aught’s: anomalously low extent, as seen in this graph. There were only a handful of times when global ice extent was significantly above the climatological average these past 10 years and none had the magnitude of the record low extents seen in 2007 and 2008. When viewed in the long term, it is clear to see that the state of the poles has shifted in the past 10 years. The majority of that state change has been in the Arctic.