Arctic melt goes into overdrive

Earlier this year, we saw the unprecedented disappearance of sea ice from the Bering Sea during a time of year when it should be gaining ice. This trend toward plummeting sea ice in the Alaskan and Canadian Arctic continues, this time centered in the Chukchi and Beaufort seas.

Why it matters: Sea ice loss is disrupting the balance of heat in the Northern Hemisphere, and it is reverberating throughout ecosystems, causing everything from plankton blooms near the Arctic Ocean surface to mass haul-outs of walruses in Russia and Alaska. It may also be disrupting weather patterns across the Northern Hemisphere.

The big picture: Across the entire Arctic, sea ice extent is at a record low for this point in the year, and depending on weather conditions during the summer, it's possible that 2019 could set a new record low ice extent.

• The all-time record low sea ice extent was set in 2012, although subsequent years have nearly beaten that mark.
• So far, weather conditions have favored an early start to the Greenland ice melt season, too, and ice melt there, unlike disappearing sea ice, contributes to global sea level rise.
• The portion of Greenland experiencing melting ice hit a record high for the date on June 13, with temperatures rising to near freezing at Summit Station, in the center of the ice sheet.
• The Arctic is warming at more than twice the rate of the rest of the world.

What they're saying:

• "At the moment, you can essentially sail uninterrupted from the North Pacific to the Canadian Arctic," says Zack Labe, a climate scientist and Ph.D. candidate at the University of California, Irvine.

• "The Arctic is a regulator of Northern Hemisphere climate, and while the ice that is melting now isn't going to affect whether you get a thunderstorm tomorrow, in the long term, these are going to have profound effects on your weather and climate down the road that you will have to take action on, like it or not," says Rick Thoman of the University of Alaska at Fairbanks.

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