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Ice Loss Continues To Set Records

by Rod Hill

Bio | Email | Follow: @kgwrodhill

kgw.com

Posted on December 6, 2012 at 3:27 PM

Updated Wednesday, Oct 30 at 6:40 AM

The image below shows the September record for low ice coverage over the Arctic.  Scientists say measured ice Sept. 16th covered an area 18 percent smaller than the previous record and nearly 50 percent less than average coverage  from 1979 to the year 2000.  The previous record for low aerial coverage of ice was set back in 2007.

 

It can be hard to imagine how radical a transformation the loss of so much ice is. Most of us live in a world where snow and ice are transient things, momentarily hiding the “real” landscape. In the Arctic, ice is the real landscape, and for it to have shrunk to half its historic summer extent is as much a transformation of the environment as if half the forests of New England had been replaced by Saguaro cactus.

The transformation from icy to ice-free has ecological consequences and physical ones. The loss of sea ice directly affects polar bears, seals, walruses, and many birds, for which the sea ice is a raft, a place to haul out, rest, feed, and give birth. The “where, when, and what kind” of blooms of phytoplankton—the foundation of the marine food web—is changing, and those changes cascade through fish populations.

The most profound physical impact ice loss is that the loss becomes a sort of “self-fulfilling prophecy.” Less ice turns Arctic latitudes from a bright white solar reflector into a dark expanse of open water: a black t-shirt on a summer day. The more ice that melts, the more sunlight the ocean absorbs. The more sunlight the ocean absorbs, the warmer it gets, and the more ice melts.

That self-reinforcing feedback loop is the heart of the process that scientists refer to as “Arctic amplification” of global warming, and it explains why temperatures have risen faster in the Arctic than they have at temperate latitudes.

The above article is courtesy of NOAA.  More on Arcitc warming, including a ten degree warm up over the historic temperature average can be found at: 

www.noaanews.noaa.gov/stories2012/20121205_arcticreportcard.html

Meteorologist Rod Hill

  

 

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