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Posted on January 8, 2009 @ 08:00:00 AM by Paul Meagher
The following graph is getting quite a bit of buzz these days. Before you read any of the buzz, I would suggest that you study the graphic carefully to formulate your own conclusions.
credits: http://www.boingboing.net/2009/01/07/sea-ice-area-returns.html
View enlarged version.
Another resource you might want to consult to learn more is the Arctic Climate Research at the University of Illinois which is the source of this image. If you visit the site you will see that this image is but one image in a fascinating gallery of images called "The Cryosphere Today" that seeks a deeper understanding of Artic climate dynamics.
Before I leave this topic, I should address one of my concerns about the buzz this graph is creating. There are many commenters claiming that this is disproof of global warming and/or that scientists don't really know anything about global warming. I think those of us who believe in global warming should retain an open mind and seriously reflect upon a graphic like this and what it might mean. Tim Flannery is addressing global warming skeptics in his native Australia who are critizing him for not getting his dire water predictions correct. His response is instructive and consists of two parts:
- Look at long term trends to make up your mind not weather patterns over a short period.
- No one can predict individual events, all they can do is asign a level of risk to whether they might occur or not. In some cases the failure of predictions to occur is because large investments were made in light of assessed risk.
The other response is to admit that global warming is a complex phenomenon with unexpected dynamics. In the Daily Tech article "Sea Ice Ends Year at Same Level as 1979", Micheal Ascher reports the explanation that scientists have given for this phenomonon:
Earlier this year, predictions were rife that the North Pole could melt entirely in 2008. Instead, the Arctic ice saw a substantial recovery. Bill Chapman, a researcher with the UIUC's Arctic Center, tells DailyTech this was due in part to colder temperatures in the region. Chapman says wind patterns have also been weaker this year. Strong winds can slow ice formation as well as forcing ice into warmer waters where it will melt.
Why were predictions so wrong? Researchers had expected the newer sea ice, which is thinner, to be less resilient and melt easier. Instead, the thinner ice had less snow cover to insulate it from the bitterly cold air, and therefore grew much faster than expected, according to the National Snow and Ice Data Center.
There are appear to be some powerful homeostatic tendencies in sea ice formation. The dynamics here are very interesting and to the extent that we can better understand them we should be able to come up with better climate prediction models.
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