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Government scientists released this year's Arctic Report Card today, and researchers say the Arctic continues to warm up at rates they call astonishing. NPR's Christopher Joyce has the details.
CHRISTOPHER JOYCE, BYLINE: On average, the Earth is warming up, but the top of the planet is really getting toasted.
JEREMY MATHIS: The Arctic as a whole is warming at least twice as fast as the rest of the planet.
JOYCE: Jeremy Mathis is a climate scientist at the National Oceanic and Atmospheric Administration and one of the report card's authors. There's a feedback loop behind this warming. Normally the Arctic stays cool because snow and ice reflect a lot of sunlight back into space, but warmer temperatures are melting that snow and ice. The darker ground and water that are exposed then absorb more heat, and that makes the Arctic warm up even faster. Mathison (ph) adds that the warming is getting progressively worse.
MATHIS: The Arctic is getting persistently warmer. Sea ice is continuing to show declines, particularly during the summer months.
JOYCE: And now, Mathison says, the Arctic winter is warming faster as well.
MATHIS: The second big story for 2016 has been the winter temperatures.
JOYCE: Mathis says it wasn't so long ago that the temperature in Fairbanks, Alaska, where he lives would drop to minus 40 for weeks at a time in the winter.
MATHIS: And now, since about 2012 or 2013, it's pretty rare for the temperature to even hit minus 40 in Fairbanks.
JOYCE: Warmer winters have created what polar scientist Marco Tedesco calls a new precondition for a higher rate of melting in the spring. That's when the sun rises again, ending a dark Arctic winter.
MARCO TEDESCO: You change the physics of the snowpack, and so that snow becomes more vulnerable to melt sooner as soon as the sun comes up.
JOYCE: Tedesco from the Lamont-Doherty Earth Observatory in New York says polar regions are not as resilient to warming as other places. That's because it only takes one or two degrees to change the Arctic from a frozen world to an unfrozen and very different one.
TEDESCO: In other places, going from - oh, I don't know - 75 degrees Fahrenheit to 80 degrees Fahrenheit - it might not be - make such a great difference. But if you cross the melting point, you basically are stepping into a completely new world.
JOYCE: A world that scientists say is changing more rapidly than they've ever seen. Christopher Joyce, NPR News.
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