Wednesday, January 28, 2009

Antarctic Warming

In recent decades, rapid warming of the western edge of the Antarctic Peninsula has seen plants moving in to colonize the area and Adélie penguins moving out. Some, including "skeptics" have argued that the warming — which has been disproportionate to that seen in most parts of the world — was a localized phenomenon, and that the bulk of the continent's interior was actually cooling. It isn't. In a new study just published in the January 29th issue of Nature, Eric Steig and his colleagues compared 26 years of temperature measurements from the NOAA AVHRR satellite sensor, with simultaneous weather station measurements, and found a gradual, decades-long warming trend.

The image above, taken from NASA's Earth Observatory, and based on the analysis of weather station and satellite data, shows the continent-wide warming trend from 1957 through 2006. Dark red over West Antarctica reflects that the region warmed most per decade. Most of the rest of the continent is orange, indicating a smaller warming trend, or white, where no change was observed.

Steig's results (on the right) are similar to those of the Intergovernmental Panel on Climate Change (on the left).


1 comment:

Richard Badalamente said...

Eric Steig wrote to me in an email:
I should note that your statement on the blog that
"scientists thought that the warming — which has been disproportionate to that seen in most parts of the world — was a localized phenomenon"
is not really quite right. While this idea that Antarctic warming was spatially limited is widely cited, and was perhaps widely thought, it was never actually supported by any publication I'm aware of. For example, the 2007 IPCC report gives a result very similar to our paper. Compare this figure (from IPCC): http://www.realclimate.org/images/ant_temp_ipcc_3.7c.jpg
with our results
http://www.realclimate.org/images/steig1.jpg
More details at
http://www.realclimate.org/index.php/archives/2009/01/warm-reception-to-antarctic-warming-story
This is all sort of a distraction, but I mention this because prominent "skeptics" have made much use of the idea that our results somehow contradict earlier work. But they don't. They merely make the picture clearer.
Thanks for the clarification, Eric.