Federal scientists on Thursday issued their annual "Arctic Report Card," citing "consistent evidence" of warming in three key indicators: the atmosphere, sea ice and Greenland's ice sheet.
"The Arctic we see today is very different from the Arctic we saw even five years ago," Jackie Richter-Menge, the report’s chief technical editor, said in a statement. "It’s a warmer place with less thick and more mobile sea ice, warmer and fresher ocean water, and increased stress on caribou, reindeer, polar bears and walrus in some regions."
The Obama administration was quick to echo the findings. "Scientists are seeing drastic changes in the region from just five years ago and at rates faster than anticipated, the National Oceanic and Atmospheric Administration said in a statement accompanying the report card.
Richard Spinrad, head of research at NOAA, said the report shows that warming temperatures are changing wind patterns in the Arctic, melting sea ice and glaciers, and affecting ocean and land life.
The Arctic is a sort of natural regulator in terms of the amount of heat stored in the ocean and ice, Spinrad told reporters, and "especially the loss of sea ice is messing with that thermostat for the whole globe."
A particular problem is the disappearance of old, thick sea ice that has been present for thousands of years, added James Overland of NOAA's Pacific Marine Environmental Research Laboratory. "It's very difficult to get that (ice) back," he said.
Among the findings of the update:
- Air temperatures over the Arctic Ocean reached an unprecedented 7 degrees Fahrenheit above normal in October-December of 2008.
- There is evidence that the higher air temperatures are causing changes in the air circulation in both the Arctic and northern mid-latitudes.
- The area covered by sea ice this summer was 25 percent below the average from 1979 to 2000 and was the third lowest since satellite records were begun in 1979.
- The melting ice resulted in an unprecedented amount of fresh water in the surface layer of the Arctic Ocean.
- "Record-setting summer temperatures around Greenland" led to further melt of the ice sheet.
- The amount of land covered by snow in the winters of 2007-08 and 2008-09 continued the trend toward shorter snow seasons due to earlier spring melt, although there is considerable annual and regional variability.
The Arctic Report Card has been issued annually since 2006.
The 2009 report card cited "many indications of warming" for the three other tracked indicators: wildlife biology, the ocean and land.