Bleak U.S. "report card" finds warming Arctic

By Deborah Zabarenko, Environment Correspondent

WASHINGTON (Reuters) - A bleak "report card" on global warming's Arctic impact released on Wednesday found less ice, hotter air and dying wildlife, and stressed that what happens around the North Pole affects the entire planet.

The report, issued by the U.S. National Oceanic and Atmospheric Administration, also found that weird winds blowing warm air toward the North Pole and unusually persistent sunshine added to the warming trend.

Unlike previous years, when there have been hot spots and cold spots at different times in the Arctic, "winter and spring, the temperatures are all above average throughout the whole Arctic and all at the same time," said James Overland of NOAA's Pacific Marine Environmental Laboratory in Seattle.

"This is an unusual feature and it looks like the beginning of a signal from global warming," Overland said in a telephone news briefing.

The report gave red "stoplights" to conditions in the atmosphere and sea ice to show scientists have "a high level of confidence that things there are showing dramatic effects due to the warming temperatures," said Jacqueline Richter-Menge of the Army's Cold Regions Research and Engineering Laboratory in New Hampshire.

The report also gave yellow "caution lights" -- indicating mixed signals -- on conditions of the Greenland ice sheet, North Pole ocean temperatures, wildlife and permafrost.

There were no green lights, which would have indicated "all systems were OK," according to Richter-Menge.

The NOAA report was in keeping with similarly gloomy news about the Arctic released in recent weeks:

-- On September 7, the U.S. Geological Survey said two-thirds of the world's polar bear population could be gone by mid-century if predictions of melting sea ice hold true.

-- On September 20, the U.S. National Snow and Ice Data Center reported that Arctic sea ice melted to its lowest level ever, a decrease of 23 percent from the previous record and a 39 percent drop from the long-term average.

PERMAFROST AND REINDEER

Environmental observers focus on the Arctic because it has long functioned as Earth's air conditioner, cooling the planet with reliable stores of sun-reflecting sea ice.

The sea ice melts and re-freezes seasonally but recent years have shown a smaller area of maximum sea ice in the winter, indicating it is more difficult to restock the supply of polar ice after a record summer melt like this year's.

Another indicator of climate change is the condition of permafrost, the ground that has been frozen solid for centuries.

Permafrost all around the Arctic started warming up in the 1970s and 1980s, but the warming slowed by the mid-1990s and showed almost no change by 2000, said Vladimir Romanovsky of the University of Alaska at Fairbanks.

This shows that whatever is causing the permafrost to get warmer, it is consistent around the hemisphere, from Alaska to Greenland to Siberia, Romanovsky said.

Mike Gill of the Circumpolar Biodiversity Monitoring Program noted that Arctic biodiversity has a global impact, since hundreds of bird species and several marine mammal species migrate from the Arctic to all parts of the Earth except the interior of Antarctica.

Gill noted that some reindeer and caribou herds, on which local populations depend, have declined up to 80 percent, while some goose populations have doubled, contributing to overgrazing.