WASHINGTON — While some indicators have stabilized, the Arctic is seeing significant changes from warming temperatures and shrinking sea ice, the Bush administration said Wednesday in an annual report card on the region.
Sea ice fell well below the previous record, caribou are declining in many areas and permafrost is melting, according to the State of the Arctic report issued by the National Oceanic and Atmospheric Administration.
"The bottom line is we are seeing some rapid changes in the Arctic," said Richard Spinrad, assistant administrator for oceanic and atmospheric research at NOAA.
And unlike Las Vegas, "what happens in the Arctic actually does not stay in the Arctic," he added, playing on a well-traveled slogan of the gambling mecca.
Scientists have expected polar regions to feel the first impacts of global warming and the 2006 State of the Arctic report provided a benchmark for tracking changes.
Red and yellow marks
Wednesday's follow-up was the first update, marking the atmosphere and sea ice indicators in red. The other indicators — Greenland, ocean, biology and land — were marked in yellow, or caution.
Winter and spring temperatures were all above average throughout the whole Arctic, said James Overland of NOAA's Pacific Marine Environmental Laboratory in Seattle.
"This is unusual and looks like the beginning of a signal from global warming," Overland said in a telephone briefing.
If you go back 100 years, it would be warm in one part of the Arctic and cold in another, Overland said. "We're not getting that now."
Sea ice cover this year is 23 percent smaller than the past record low set in 2005 and 39 percent less than average, said Jacqueline Richter-Menge of the Cold Regions Research and Engineering Laboratory in Hanover, N.H.
She noted that the amount of older ice in the Arctic is significantly reduced, which makes it much more sensitive to change.
Vladimir Romanovsky of the Geophysical Institute at the University of Alaska at Fairbanks, said the warming is affecting the permafrost in Siberia, Alaska and other regions.
"This similarity of very different regions shows the changes are not local, they are on at least a hemispherical scale," Romanovsky said.
The report card did note that some permafrost areas appear to be stabilizing and that the deep waters off Alaska appear to be cooling.
But it emphasized that "collectively, the observations indicate that the overall warming of the Arctic system continued in 2007."
Some Caribou declines
Mike Gill, of the Circumpolar Biodiversity Monitoring Program in Whitehorse, Canada, said the largest declines in caribou are centered over Canada and parts of Alaska.
The herds are sensitive to changes in their range and sometimes have problems migrating in changing conditions, meaning that calving occurs before they get to new feeding grounds, resulting in higher mortality.
The tundra itself is "shrubifying," he said and the increased shrub cover over many regions affects habitat and local climate, since it tends to absorb more solar radiation.
The global goose population has been on the increase, he added, resulting in overgrazing in some areas.
The full report card is online at www.arctic.noaa.gov/reportcard/.
The Associated Press contributed to this report.