I referenced a Climate Central article by Alyson Kenward when I had Bebbo and Kito discuss the impact of Arctic ice melt on global warming in a recent post. But I wanted to take this opportunity to address some enlightening information in Kenward’s piece that I didn’t highlight last time. The story addresses how snow and ice play a crucial role in sending unwanted heat from the sun out of our atmosphere. But, as University of Michigan climatologist Mark Flanner tells Kenward, the time and place in which the snow is reflecting sunlight are very important:
The average changes in reflectance that Flanner and his colleagues measured are based on data gathered throughout the year, but Flanner says that the loss of spring and summer sea ice had a disproportionately large impact on the reflectivity decline. In the Northern Hemisphere, the late spring and summer months see many more hours of sunlight than the fall and winter, so the summer sea ice extent, which has been decreasing dramatically in recent years, plays a big role in how much the cryosphere cools the hemisphere, and the planet.
“We’ve seen an increase in fall snow cover in some places, but if you lose a square meter of snow in May and you gain a square meter in November, it’s not a wash,” he explains.
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Interview: Katie Kline, Communications Officer at Ecological Society of America interviewed me via Skype for the ESA’s Ecotone blog. Read and hear it here.