I'll be regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2006-2009. The JAXA graph is favoured by almost everyone, probably because it looks so nice compared to other graphs (like the one by Arctic ROOS, the University of Bremen and the Danish Meteorological Institute). All the years have a nice colour of their own which makes it easy to eyeball the differences between trends. Most of the betting on minimum SIE is based on the IJIS data. NSIDC has a nice explanation of what sea ice extent is in their FAQ.
June 29th 2010
I have been writing these SIE updates every 3 days, but things are changing so fast at the moment that I've decided to do an update at least every second day. I think that's not unwise with the July onslaught about to start.
So what happened in the past 2 days? On the first day we almost had another century break: 96,094 square km. This was easily compensated by yesterday's melt which was reported to be a whopping 141,975 square km, 2010's 5th century break in June, equalling the 2007 record. 2010 has 2 more days to claim a new record for June. Either way, 2010 has extended its lead over 2007 by another 79K since the last SIE update. Will it be enough to withstand 2007's awesome run of 10 century breaks in just 15 days (including a double century break, ie more than 200K in one day) that started on tomorrow's date?
In the next 2-3 days there's a good chance as well that 2010 will lead 2008 and 2009 by more than 1 million square km, as these two years didn't start producing century breaks until July 2nd. The current difference between 2010 and the other years is as follows:
- 2009: -982K
Kelly O'Day produced this chart that shows average daily melt for June:
Here's the IJIS graph:
I'm sure everybody is curious to see what happens next. Steven Goddard has proclaimed that 'in
three days, the slope of the Arctic extent graph will begin to drop off' because all the ice in Hudson Bay has melted spectacularly fast and there's none left. He could be right, especially as the Arctic Oscillation remains negative for the time being. But somehow Goddard's track record doesn't inspire confidence, and that's putting it mildly. Let's see what happens.
TIPS - Other interesting blog posts and news articles concerning Arctic ice:
Patrick Lockerby has written a new blog post: Arctic Ice July 2010. I suggest reading that twice. His track record for this year has been very good so far and his "prediction for July is that Arctic sea ice loss will accelerate."
A new study shows the Arctic climate system may be more sensitive to greenhouse warming than previously thought, and that current levels of Earth's atmospheric carbon dioxide may be high enough to bring about significant, irreversible shifts in Arctic ecosystems. Read on.
There's a fantastic must-read article on the BBC Science & Environment webpage explaining what the recently launched Cryosat-2 satellite will be doing the coming 5 years. It will put the PIPS 2.0 vs PIOMAS controversy to rest, that's for sure (if this season's melt doesn't do that beforehand). The scientific community is about to be fed indispensable data from this satellite.