Arctic Snow Cover Shows Steep Decline
The blanket of snow that covers Arctic regions for most of the year has been shrinking at an increasing pace over the past decade, researchers say.
A recent study found an overall decrease in Arctic snow-cover extent (snow that covers the Arctic at the end of the spring) from 1967 through 2012, and an acceleration of snow loss after the year 2003. The rate of snow-cover loss in June between 1979 and 2012 was 17.6 percent per decade (relative to the 1979-2000 mean), which is greater than the rate of September sea-ice decline during that same period, the researchers say.
Snow cover extent anomalies for every third year from 1967 through 2012. Each June's snow cover is compared to the 1971–2000 mean. Above-average extent appears in shades of blue, and below-average extent appears in shades of orange.
CREDIT: Robert Simmon, NASA Earth Observatory
In fact, sea-ice extent — the area of ocean with at least 15 percent ice cover — reached a new record low in September, dwindling to 1.32 million square miles (3.41 million square kilometers), according to the U.S. National Snow & Ice Data Center, which tracks sea ice with satellite data.
The link between snow-cover and sea-ice extent is not completely understood. "But if you remove snow cover earlier, you're creating the potential to send warmer air out over the ocean. It can't be good for sea ice if you lose the snow early," study researcher Chris Derksen, a cryosphere scientist at Environment Canada in Toronto, told Nature News. [10 Key Facts About Arctic Sea Ice]
Read the rest of the article here.
Commenter Dominik Lenné has a short summary of what it all means on his Remarks and Observations blog.