Monday 15 July 2013

Signs of melt at North Pole

Melt Puddles, Distant Open Water Visible at North Pole Camera 2

(Melt Puddles and Distant Open Water at North Pole Camera 2 on July 13. Image source: APL)


13 July, 2013

With the emergence then fading of a ‘warm storm’ in late June and early July, then a subsequent set of intermittent storms and sunny days, all occurring in warmer than freezing conditions, central Arctic surface ice melt has continued to proceed apace.


This melt is now plainly visible at North Pole Camera 2 were a number of near-camera melt puddles have been forming and growing over the past few days. You can see these melt puddles clearly in the above image provided by the Applied Physics Lab through its North Pole Camera #2. The puddles, which were at first in the front field of the camera, have now expanded to cover about 105 degrees of the view provided. Smaller, darker melt spots also appear to have invaded behind the markers set around the camera.
In the distance, in the left-hand field of view, a larger section of dark water appears to have opened as well. This darker, open section, which has been an intermittent feature since late June, seems to have grown of late, with larger gaps appearing in this more distant section.


(Image source: Uni Bremen)
Since early July, rapid extent and area melt have continued apace as a strong high pressure system formed over the Beaufort and a series of intermittent storms rushed through the Central Arctic via origins in the Laptev, Barents, Kara, and extreme North Atlantic. Central sea ice concentration has remained low due to damage during June’s PAC 2013 and now three melt tongues are plunging into the Arctic — one from the Chukchi, one from the Laptev and one from the Kara and a broad region all the way to the Fram Strait. More gradual melt is also proceeding from the Mackenzie Delta even as ice in the Canadian Archipelago gradually collapses. Hudson and Baffin Bays, as you can see in the above image provided by Uni Bremen are mostly cleared out. These conditions: three areas of rapid melt at the ice edge combined with continued low concentration, melting ice at the Arctic’s heart, represent high risk for further rapid melt through late July. This is especially due to the fact that many ice regions are now at risk of separation from the main ice pack or from surrounding by open water on three sides. Such circumstances usually enhance ice fragility and result in greater ice vulnerability to disruptive weather events come late summer. It’s a set of conditions we’ll explore more deeply in a blog I’m preparing for next week.
For now, though, it is sufficient to show that Central Arctic regions are still undergoing surface melt even though the forces driving rapid bottom melt and dispersal appear to have abated for the moment. We’ll also be keeping an eye on ECMWF forecasts which show a 985 or stronger low forming directly over the North Pole for a few days next week. Another warm storm potential that may have further impacts as sunlight has now had the opportunity to warm areas of water beneath the fractured ice.


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