NOAA flies over the Arctic to measure sea ice coverage. The extent of sea ice in Sept. 2014 was the sixth lowest since satellite observations began in 1979. (NOAA)

Air temperatures at the top of the world continue to rise twice as fast as temperatures in lower latitudes, causing significant ice melt on land and sea, and affecting populations of polar bear and migrations of fish, a federal report released Wednesday said.

As a result of the Arctic temperature rise, an effect of global warming, Alaska recorded temperatures nearly 20 degrees higher than the January average as warm air flowed north, according to an Arctic Report Card issued by the National Atmospheric and Oceanic Administration.

In April, the amount of snow in Eurasia -- the land mass that comprises Asia and Europe -- hit its lowest level since satellite observations began in 1979, and the June snow in North America was the third lowest on record, said Jacqueline A. Richter-Menge, a senior research engineer for NOAA’s Cold Regions Research and Engineering Laboratory.


(Kathy Crane/NOAA)

“Snow disappeared three to four weeks earlier than normal in western Russia, Scandinavia, the Canadian sub-Arctic and western Alaska due to below average accumulation in winter and above normal spring temperature,” said Richter-Menge, a co-editor of the report card, which was first published in 2006 and updated each year since.

Sixty-three scientists from 13 nations served as co-authors of the report. They produced 10 essays on the Arctic’s air temperature, sea and ocean temperature, snow cover, Greenland ice sheet and vegetation, among other topics. A special essay this year focused on the effect of warming on polar bears.

The report was peer reviewed by the Arctic Monitoring and Assessment Program of the Arctic Council and released in San Francisco at an annual gathering of the American Geophysical Union.

This year’s findings underscored an observation made by University of Virginia environmental professor Howard Epstein last year: “The Arctic is not like Vegas. What happens in the Arctic doesn’t stay in the Arctic.”

“Arctic warming is setting off changes that affect people and the environment in this fragile region,” said Craig McLean, the acting assistant administrator for NOAA research, “and has broader effects beyond the Arctic on global security, trade and climate.”

Geoff York, senior director of conservation at Polar Bears International, wrote about the effect on the region’s largest predator.

York wrote that their population declined from about 1,200 to 800 in the western Hudson Bay area of Canada between 1987 and 2011, largely because the sea ice breaks up earlier and freezes later, and has a short season overall. Bears depend on sea ice to travel, mate and hunt.

But there is slightly good news for the bears. In the southern Beaufort Sea, the numbers of adult bears have stabilized at about 900 after a 40 percent decline from their population in 2001. In another part of the Arctic, the Chukchi Sea, bears are rebounding from a “significant harvest in the mid-1990s,” York said. Sea ice is declining in the area, but not as rapidly as other areas.