A new entry at the National Snow and Ice Data Center out of Colorado is out and the news is that even with this years La Nina induced cold temperatures in parts of North America, the trend of diminishing Arctic sea ice shows little sign of abating.
On February 28, Arctic sea ice reached its maximum extent for the year, at 15.14 million square kilometers (5.85 million square miles). The maximum extent was 720,000 square kilometers (278,000 square miles) below the 1979 to 2000 average of 15.86 million square kilometers (6.12 million square miles), making it the fifth-lowest maximum extent in the satellite record. The six lowest maximum extents since 1979 have all occurred in the last six years (2004 to 2009).
I’m cross posting this post on my weather blog at alberniweather.ca as well.
My, unscientific opinion based on what I’ve read, is that this year was a relatively strong La Nina year, this led to a cooler, drier regime for most of North America, however it also meant that more of the warm Pacific wind was instead pushed up into the Arctic through the Bering Strait, negating some of that increased cold…
La NiÃ±a is expected to gradually weaken with increasing chances (greater than 50%) for ENSO-neutral conditions during the Northern Hemisphere Spring.
Expected La NiÃ±a impacts during March-May 2009 include above-average precipitation over Indonesia, and below-average precipitation over the central equatorial Pacific. Compared to the Northern Hemisphere winter, La NiÃ±a impacts over the United States are typically less pronounced. For the contiguous United States, potential impacts include below-average precipitation across the southern states. Other potential impacts include below-average temperatures in the Pacific Northwest and above-average temperatures across much of the southwestern and south-central United States.
…. nearly all the model forecasts for the NiÃ±o-3.4 region show that La NiÃ±a will have dissipated by May â€“ July 2009, the exact timing of the transition to ENSO-neutral conditions is uncertain (Fig. 5).
If things go as they did last year with similar conditions then I’d expect Artic ice to again be low, but not set a new record. I think we would be very unlucky to set another new record this year for minimum sea ice… and if we did, it would be an extremely bad sign indeed.
We will get an authoritative forecast possibly from the NSIDC in the next couple weeks.