As the strands of our planet's environment continue to come unraveled no place is changing more drastically over the short term than the Arctic and Antarctic. A new report has more confirmation of the alarming trends scientists have seen in the Arctic recently.
Arctic has taken a turn for the warmer
Scientists see pervasive and permanent changes in the last five years
By Janet Raloff
The northern polar region’s climate has materially changed over the past five years, a team of 121 scientists from 14 nations concludes in a December 1 Arctic report card. Compared with 2006 and earlier, they note, the Arctic is warmer and less icy.
Sufficient observational data now exist “to indicate a shift in the Arctic Ocean system since 2006,” says Jacqueline Richter-Menge of the U.S. Army’s Cold Regions Research and Engineering Laboratory in Hanover, N.H., a coeditor of the new analysis. “This shift is characterized by the persistent decline in the thickness and summer extent of sea-ice cover and by a warmer, less salty upper ocean.”
Triggering that turning point, Richter-Menge says, were unusually warm Arctic temperatures in 2006 together with a persistent weather pattern that pushed ice across the Arctic and into the North Atlantic through the Fram Strait east of Greenland: “We like to call it the perfect storm of the Arctic.”
“We’ve got a new normal,” concludes Don Perovich of CRREL.
Regional warming and melting of land ice cover have also continued at a record pace, the new report finds. For instance, satellite data show that the loss of ice from Greenland during 2010 to 2011 was the largest since monitoring began in 2002. In the Canadian Arctic, the duration of 2011 lake-ice cover was shorter by four to five weeks compared to what had been the average between 1997 and 2010.
For a decade, monitoring systems have detected continuous warming at Arctic sites near the coast, accompanied by a greening of the landscape as reduced snow cover has allowed small shrubs to grow bigger and seeds of trees and other plants to germinate in formerly frozen soils.
Winters in the Canadian Arctic are four to five weeks shorter over the span of just a few years.
If you're not alarmed by these rapid and permanent changes, then you should be.