That warming of the air and ocean impacts land and marine life and cuts the amount of winter sea ice that lasts into the following summer, according to the report.
In addition, wild reindeer and caribou herds appear to be declining in numbers, according to the report.
The report also noted melting of surface ice in Greenland.
“Changes in the Arctic show a domino effect from multiple causes more clearly than in other regions,” said report author James Overland, an oceanographer at NOAA’s Pacific Marine Environmental Laboratory in Seattle.
“It’s a sensitive system and often reflects changes in relatively fast and dramatic ways.”
Researchers at the National Snow and Ice Data Centre, part of the University of Colorado, reported last month that Arctic sea ice melted to its second-lowest level this northern summer.
The 2008 season, those researchers said, strongly reinforces a 30-year downward trend in Arctic ice extent – 34 per cent below the long-term average from 1979 to 2000, but 9 per cent above the record low set in 2007.
Last year was the warmest on record in the Arctic, continuing a regionwide warming trend dating to the mid-1960s. Most experts blame climate change on human activities spewing so-called greenhouse gases into the atmosphere.