According to the annual Arctic Report Card, released Tuesday by the National Oceanic and Atmospheric Administration (NOAA), the Arctic is warmer than ever. The average air temperature over Arctic land reached 2.3 degrees Fahrenheit above average for the year ending in September. That's the highest since observations began in 1900.
"Warming is happening more than twice as fast in the Arctic than anywhere else in the world,” said NOAA chief scientist Rick Spinrad, at a meeting in San Francisco, California. “We know this is due to climate change.”
A Changed Environment
The Arctic is a polar region at the northernmost part of the earth. It centers on the North Pole and reaches into North America and Eurasia. With these record-high temperatures, the sea ice that forms when Arctic Ocean water freezes is melting. Even when the ice reached its peak coverage this past February, it was at its lowest amount since records began in 1979. The minimum ice coverage, reached in September, was the fourth lowest on record.
Melting ice takes a toll on animals, including walruses. Usually, these marine mammals haul themselves onto ice floes, or sheets of floating ice, to mate and give birth. But finding little ice, the walruses in Northwest Alaska have lately been crowding onto beaches. This is new behavior, and it can cause big problems, according to Martin Jeffries of the federal Office of Naval Research and Jackie Richter-Menge of the U.S. Army Corps of Engineers. Crowds can lead to stampedes, putting baby walruses, called calves, in danger.
Snow cover in June in both the North American and Eurasian parts of the Arctic was at the second lowest level since scientists began recording in 1967. With less snow covering the ground, more sunlight gets through to the land, which soaks up the energy and gets warmer. June snow cover has been dropping by 18 percent every ten years since 1979, according to the study.
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