SOLAR TODAY - May 2009

Arctic sea
ice Age,
sept. 2007
and 2008

NAtio NAl s Now ANd iCe d At A Ce Nter

A comparison of Arctic sea ice age in September 2007 (left) and September 2008 (right) shows the increase in thin first-year ice (red) and the decline in thick multi-year ice (orange and yellow). White indicates areas of ice below about 50 percent, for which ice age cannot be determined.

The revelations at AAAS came on the heels of a new journal article by the National Oceanic and Atmospheric Administration’s Susan Solomon, co-chair of the 2007 IPCC Working Group I. In “Irreversible Climate Change Due to Carbon Dioxide Emissions,” published in the Feb. 10 issue of the Proceedings of the National Academy of Sciences, she and her co-authors argue that “climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for more than 1,000 years after emissions stop.” Model results cited in the paper indicate that if atmospheric carbon dioxide rises from its current level of 386 parts per million to 450–600 ppm, impacts include “irreversible dry-season rainfall reductions in several regions comparable to those of the ‘dust bowl’ era as well as inexorable sea level rise.”

Solomon has a reputation for stating findings in a scientific, objective and understated manner. When she starts talking about irreversible impacts this century in several locations around the world that are akin to the American Dust Bowl of the 1930s, we should all take climate change very seriously.