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Why Arctic is warming twice as fast as rest of planet

A new report from NOAA indicates that the Arctic is warming faster than any other part of the world for the second straight year in a row.

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Jonathan Hayward, The Canadian Press/AP/File
This 2008 file photo made with a fisheye lens shows ice floes in Baffin Bay above the Arctic Circle, seen from the Canadian Coast Guard icebreaker Louis S. St-Laurent.

A new report from the National Oceanic and Atmospheric Administration (NOAA) indicates that the Arctic is warming faster than any other part of the world for the second straight year in a row.

The report, which is updated annually, found that the average surface-air temperature from Oct. 2014 to Oct. 2015 was about 2.5 degrees Fahrenheit higher than the 1981-2010 baseline, and that over time, levels of snow and ice have continued to decline while Arctic river flows have increased.

The report鈥檚 authors believe that these findings could contribute to both warming seas and higher sea levels around the globe.聽

鈥淭he conclusion that comes to my mind is these report cards are trailing indicators of what鈥檚 happening in the Arctic. They can turn out to be leading indicators for the rest of the globe,鈥 NOAA chief scientist Richard Spinrad .

In 2011, NASA scientists established that the reason the earth鈥檚 poles may be warming much faster than other parts of the world is , which have brought increasingly warmer air to the poles over time. This, in turn, further accelerates melting: as more ice melts, more energy from the sun is absorbed, thereby increasing the melting rate.

These fluctuations that are causing the Arctic鈥檚 ice to melt so quickly are also making its walrus population vulnerable.

The Arctic is : younger surface ice, which tends to come and go each year, and older, denser ice, which forms the Arctic鈥檚 thicker lower layers. The Arctic is melting at such a rate that even the oldest ice layers, where walrus mothers prefer to give birth and raise their young, are melting, forcing walruses onto land. 聽聽

鈥淭his is raising concern about the that must now make feeding trips from coastal haul-outs to areas of high prey abundance 鈥 rather than utilizing nearby ice edges as they did in the past,鈥 the NOAA report鈥檚 executive summary states.

Haul outs, or large gatherings, of walruses can occur both during mating season and after. The NOAA reports that large haul-outs, which were first observed in 2007, . In 2014, 35,000 walruses were observed on a beach in Alaska, one of the largest walrus gatherings recorded.

"The massive concentration of walruses onshore 鈥 when they should be scattered broadly in ice-covered waters 鈥 is just one example of the impacts of climate change on the distribution of marine species in the Arctic,鈥 Margaret Williams, World Wildlife Fund's managing director of the Arctic program, .

These large hauls are at greater risk from the sharks and orcas that typically feed on them as they journey to their usual feeding grounds, or crushing one another in a stampede.

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