The Arctic — an area described as Earth's refrigerator because its ice helps keep temperatures cool — continues to warm up and is unlikely to return to earlier conditions, according to an annual report card issued Thursday by top scientists.
"Record temperatures across the Canadian Arctic and Greenland, a reduced summer sea ice cover, (and) record snow cover decreases" were cited as factors supporting the conclusion in the 2010 Arctic Report Card issued by the National Oceanic and Atmospheric Administration.
The report card "tells a story of widespread, continued and even dramatic effects of a warming Arctic," lead researcher Jackie Richter-Menge, an expert at the federal Cold Regions Research and Engineering Lab in Hanover, N.H., told reporters.
"It is increasingly unlikely, at least in the foreseeable future, that we will return to previous Arctic conditions," she said.
"It is very likely warming will continue" in the Arctic," she added, and "planning is urgent to adapt to the changes coming."
While 2009 saw a slowdown in Arctic warming, the report card stated, "the first half of 2010 shows a near record pace with monthly anomalies of over 4 degrees Centigrade (7 degrees Fahrenheit) in northern Canada."
Past report cards have also cited warming trends, the scientists acknowledged, but this last year has seen several anomalies: record temperatures in Greenland; a 110-square-mile piece of ice that broke off Greenland's Petermann Glacier; and a 2009-2010 winter that saw a blast of Arctic winds that went north-south instead of west-east — causing a deep freeze across the Northeast and Midwest.
That latter event, which had been registered only three times in 160 years of records, "looks like it's connecting to the warming and ice loss in the Arctic," said Jim Overland, a NOAA scientist responsible for the report card's section on atmosphere.
"Normally we think of winds bottled up in the Arctic," he said, but now a north-south shift might become more common.
"As we lose more sea ice it's a paradox that warming in the atmosphere can create more of these winter storms," he added.
In Greenland, the warmth has meant accelerated flow of melt water from glaciers into the ocean, said Jason Box, a glaciologist at Ohio State University. As a result, he added, "sea level projections will need to be revised upward."
The fourth annual report card was compiled from data and analysis contributed by 69 scientists in eight countries.
"Beyond affecting the humans and wildlife that call the area home, the Arctic’s warmer temperatures and decreases in permafrost, snow cover, glaciers and sea ice also have wide-ranging consequences for the physical and biological systems in other parts of the world," NOAA chief Jane Lubchenco said in a statement. "The Arctic is an important driver of climate and weather around the world and serves as a critical feeding and breeding ground that supports globally significant populations of birds, mammals and fish."
She also quoted a NOAA researcher in describing the Arctic's importance: "Whatever is going to happen in the rest of the world happens first, and to the greatest extent, in the Arctic."