Saturday, 10 September 2016

Open water at the North Pole

Open water nears North Pole as 2016 melt season races to finish


Mashable,
8 September, 2016



With the midnight sun sinking lower in the sky each day, now is typically the time of year when the annual summer sea ice melt slows to a crawl in the Arctic. 

But 2016 is not your typical year in that part of the world. In fact, no year is "typical" anymore for a region that is warming at about twice as fast as the rest of the globe.

Right now, broken ice and open waters are inching closer to the geographic North Pole. This is extremely rare, but likely not unprecedented, said Mark Serreze, the director of the National Climatic Data Center, in an interview.

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The state of the sea ice pack at the top of the world is a sign of the rapid pace of warming taking place there.

This year has been record warm across the Arctic, and has seen several unseasonably powerful storms swirl across the Arctic Ocean, churning the sea ice. 

Sea ice concentration as viewed by satellite, showing broken ice to greater than 87 degrees North latitude.

Sea ice concentration as viewed by satellite, showing broken ice to greater than 87 degrees North latitude.
IMAGE: UNIVERSITY OF BREMEN

The ice pack after these storms was more vulnerable to melting, since it was split into smaller chunks in greater contact with comparatively mild seawater.

In addition, a late season warm spell has propelled 2016 to run close to 2007 for the title of the second-lowest sea ice minimum on record. 

The area of open water and broken ice chunks, which could be navigable to ships, is "quite near the Pole," Serreze said, nearing 87 degrees North. 

Satellite imagery indicates the broken ice and open water may even extend to 88 degrees North in some places. (Some of the areas of broken ice are known as "polynyas," spots of  open water surrounded by ice.)

"[It's] At a very high latitude now," he said. "It's creeping closer [to the Pole] every year."

A polar buoy network that had been operating in the region could have confirmed the presence of open water at or near the Pole, but funding cuts leaves satellite imagery as the best source of data on how the melt season is progressing.


Mosaic of Sentinal-1 satellite images showing area of broken ice mixed with open water nearing the Pole.

Mosaic of Sentinal-1 satellite images showing area of broken ice mixed with open water nearing the Pole.
IMAGE: ESA

There are still at least a couple of weeks left in the melt season, meaning that the broken ice pack and open water could make it to the Pole itself, although weather conditions will have the final say in making that happen. 

Serreze said this season will end as either the second or third-lowest sea ice extent on record. 

"It's gonna be a race to the finish," he said, calling 2016 "another year in the new normal of the Arctic."



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