Sunday, 24 February 2008

Arctic Valentine

The Arctic has given us a Warm-hearted Valentine's gift!

This is going to be a short post - I keep watching Cryosphere today in order to monitor current sea ice extent. Summer's sea-ice extent loss was so dramatic I posted a couple of items, the second one being one where I predicted the amount of sea-ice for the coming winter.

Actually it looks like the majority of the winter has been better than I expected. That is, the winter was almost a record low for maximum extent wheras I expected it to be lower. In fact, for about a week, during a cold spell at the beginning of February the ice-extent was greater than a year ago by about 50k to 100k Km2.

The surprise comes in the middle of February. The Extent appears to have dropped by a stunning 700,000 Km2 in one day! When I saw it yesterday I thought it was a data error, but the extent has followed on from there instead of returning to it's previous point. So anyway, I've included an enlarged picture. It's one taken from the site, but I've enlarged it 2x and chopped out the rest of the graph. It may be that it's an error, but to give you an indication of how massive this is, it's about 5x greater than the worst single-day drop around this time last year and about 25% greater than the worst single-day drop in the record-breaking summer 2007. It means that the ice-extent (in mid-Feb) is currently at the same position as it was last April! It could go above 13M Km2, again, but given the current weather conditions near the end of February (it's quite a bit warmer than I'd expect); I'd be surprised!