Report: Arctic is keeping in more heat
Dark land is replacing the reflective whiteness in spring and summer as snow and ice decline.
WASHINGTON - The Arctic and its future are looking dimmer every year, a new federal report says.
In the spring and summer of 2014, Earth's icy northern region lost more of its signature whiteness that reflects the sun's heat. It was replaced temporarily with dark land and water that absorbs more energy, keeping yet more heat on already warming planet, according to the Arctic report card issued Thursday.
Spring snow cover in Eurasia reached a record low in April. Arctic summer sea ice, while not setting a new record, continued a long-term, steady decline. And Greenland set a record in August for the least amount of sunlight reflected in that month, said the peer-reviewed report from the National Oceanic and Atmospheric Administration and other agencies.
Overall, the report card written by 63 scientists from 13 countries shows few single-year dramatic changes, unlike other years.
"We can't expect records every year. It need not be spectacular for the Arctic to continue to be changing," said report lead editor Martin Jeffries, an Arctic scientist for the Office of Naval Research, at a San Francisco news conference Wednesday.
The report illustrates instead a relentless decline in cold, snow, and ice conditions and how they combine with each other. And several of those have to do with how the Arctic reflects sun heat.
The Arctic's drop in reflectivity is crucial because "it plays a role like a thermostat in regulating global climate," Jeffries said in an interview. As the bright areas are replaced, even temporarily, with dark heat-absorbing dark areas, "that has global implications."
The world's thermostat setting gets nudged up a bit because more heat is being absorbed instead of reflected, he said.
The Arctic has been affected more by man-made warming than the rest of the globe, Jeffries and the report said. But it comes in spurts, pauses, and drops. Not every year will be a record, Jeffries said.
For example, the Arctic sea ice's lowest point this year wasn't as small as 2012 and was only the sixth lowest since 1979. But the last eight years have all had the eight lowest amounts of summer sea ice on record, Jeffries said.
While Greenland's ice sheet lost 474 billion tons of ice in 2012, it only lost 6 billion tons last summer, the report said.