Welcome to 2012! It's a leap year, so I predict some confusion with yearly comparisons by date after March 1st. About a month later the melting seasons starts again. Time flies almost as fast as summer ice disappears!
The NSIDC has a new monthly summary out for December. The part I found most interesting:
The past two Arctic winters were dominated by a negative phase of the Arctic Oscillation, a large-scale weather pattern that brings generally warm conditions to the Arctic and colder conditions to Europe and North America. In contrast, the winter of 2011 has so far seen a mostly positive phase of the Arctic Oscillation. While temperatures were above normal in the Kara and Barents seas, the positive phase of the Arctic Oscillation tends to keep the coldest winter air locked up in the Arctic, which keeps the middle latitudes free of frigid Arctic temperatures and strong snowstorms. This weather pattern helps to explain the low snow cover and warm conditions over much of the United States and Eastern Europe so far this winter.
Several studies have shown that during the positive phase of the Arctic Oscillation, thick ice tends to move out of the Arctic through Fram Strait, leaving the Arctic with thinner ice that melts out more easily in summer. Scientists will be watching closely for this connection if the positive phase of the Arctic Oscillation continues through the winter.
Some scientists have speculated that the negative Arctic Oscillation pattern of the last two winters was in part driven by low sea ice extent. The recurrence of the positive phase of the Arctic Oscillation so far this winter, following a near-record low summer sea ice extent, does not support this thinking.
This for me was the no 1 subject of interest for this winter. If we don't see any Snowmaggedons or Snowmygawds or whatever Hollywoodesque name is assigned to blizzards by the US mainstream hysteria in the next three months, there will be a sigh of relief in Neven's house.
Another interesting thing: In the quote above it says that "during the positive phase of the Arctic Oscillation thick ice tends to move out of the Arctic through Fram Strait, leaving the Arctic with thinner ice that melts out more easily in summer". This might be true, but below average temperatures over the Canadian Archipelago and the Beaufort Sea could also make for thicker ice, especially now that NASA Finds Russian Runoff Freshening Canadian Arctic.
Last thing: how accurate is the AO bar graph right now? I've been wondering about this for a few weeks now. Eyeballing experience has given me a feeling for the correlation between the DMI sea level pressure map and the NOAA CPC AO index, but things don't seem to match up very well lately.
Take for instance today. DMI is showing a pretty big high pressure area near the centre of the Arctic:
It's been like this for a couple of days now. Added to this there's a bit of a discrepancy between the AO index graph and the AO Observed & ENSM Forecasts graph:
On the other hand, the DMI SLP map has been looking a bit weird for a couple of weeks now as well (only the big PNG available, looking less clean as usual, with a white rift in the top middle), with some slight discrepancies with the Uni Köln SLP map as well.
Ah well, it's not so important. The Daily Graphs page is a mess anyway, with IJIS SIE and SIA maps disappearing (due to failure of AMSR-E sensor, still bummed over that one) and the PIPS2 Archive demanding some sort of authentication. I'll fix things before the end of the freezing season.
Ah, and don't forget Barents. That's the exciting graph this year (starting to rival last year's Hudson Bay):