Dec 16, 2015

Arctic Report Card Shows Warming Air, Less Ice

Surface air temperatures over the Arctic have climbed 5.2 degrees Fahrenheit since the beginning of the 20th Century – more than twice the level of warming experienced elsewhere on Earth, scientists said Tuesday in an annual report.

Between October 2014 and September 2015, the average surface air temperature in the region was 2.3 degrees Fahrenheit higher than the baseline average set between 1981 to 2010 — the highest temperature in 115 years, said U.S. Army Corps of Engineers cold regions researcher Jackie Richter-Menge.

“In general, air temperatures in all seasons were above average throughout the Arctic, with extensive regions exceeding 5.4 degrees Fahrenheit over the 1981-2010 baseline,” Richter-Menge told reporters at the American Geophysical Union conference in San Francisco.

The warmer air contributed to changes in the amount of Arctic sea ice, which peaked on Feb. 25 – 15 days earlier than average. This winter ice pack was the smallest on record since 1979.

In addition, only 3 percent of the ice cover in February and March 2015 was so-called “old ice,” which is older than four years. New, first-year ice made up 70 percent of the pack, the research showed.

Three decades ago, 20 percent of the ice pack was more than four years old and just 35 percent of the pack was first-year ice, Richter-Menge said.

After the summer, the level of sea ice receded to the fourth lowest level on record since satellite observations began in 1979.

“These observations collectively confirm a trend toward a thinner and more vulnerable Arctic sea ice cover,” Richter-Menge said.

The changes are impacting Arctic marine animals, including walruses, which have taken to congregating on land, rather than sea ice, said researcher Kit Kovacs, with the Norwegian Polar Institute in Norway.

“This new haul-out behavior is raising concerns about the well-being of females and their young that must now have to make 110-mile feeding trips, each direction … rather than just simply going to nearby ice edges as they did in the past,” Kovacs said.

“Given consistent projections of continued warming temperatures, we can expect to see continued widespread and sustained change throughout the Arctic environmental system,” she added.

The changing Arctic is impacting the rest of the planet as well, said Rick Spinrad, chief scientist with the National Oceanic and Atmospheric Administration (NOAA), which released the 2015 Arctic Report Card.

Read more at Discovery News

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