Saturday, 4 June 2016

Heatwave in the Arctic

This week’s predicted ridge formation is not expected to bring with it a severe surface melt of Greenland. However, the clockwise winds driving sea ice transport may serve as yet one more heavy blow to the already greatly weakened ocean ice.”

Siberian Heatwave Wrecks Sea Ice as Greenland High Settles In

3 June, 2016
We’ve never seen Arctic sea ice extents that are as low as they are now in early June. And with Arctic heatwaves, warm winds, warm storms, and a Greenland High all settling in, something had better change soon or otherwise the ice cap over the northern Polar Ocean is basically screwed.
On the shores of the Arctic Ocean’s East Siberian Sea (ESS), near the town of Logashinko, temperatures today are expected to rise to near 80 degrees Fahrenheit. Readings that are about 40 to 50 degrees (F) above normal for this near-polar region during this time of year.
(Welcome to increasingly ludicrous climates. Temperatures near 80 F at Logashinko, Russia are at least 40 degrees F above average for this time of year. A place well north of the Arctic Circle, but whose temperatures are predicted today to match those of St. Martin Island in the tropics. Image source: Earth Nullschool.)

We would have never expected temperatures to have risen so high near typically frozen Logashinko during early June sans the heating effect of atmospheric CO2 levels that have this year peaked near 407.5 parts per million. The highest levels seen on Earth in about 15 million years. These scorching polar temperatures were driven north by a powerful high amplitude ridge in the Jet Stream that has dominated Eastern Russia for much of 2016 Spring. This expansive ridge enabled extreme wildfires popping up all over the region even as it today drives 80 degree weather all the way to Arctic Ocean shores — enforcing a regime of rapid sea ice melt over the East Siberian Sea.
ESS, Laptev Get Ripped Up

As the warm winds drive northward across ice-clogged Arctic Ocean waters, temperatures rapidly fall into 35 to 41 degree (F) ranges. And though that may sound cool to the casual observer, for the East Siberian Sea zone during early June, that’s scorching hot — topping out at more than 10 degrees above average for some areas. A pretty extreme variation for late Spring when temperatures over the Arctic Ocean only typically depart from average by about 3 or 4 degrees at most.
East Siberian Sea Melting
(The Laptev and East Siberian Sea Ice is getting ripped up by extreme Arctic warmth. The blue tint to ice in the above image indicates melt ponds, while dark blue indicates open water. Zooming in closer reveals the brown flush of warm waters issuing from heated Siberian rivers. Image source: LANCE MODIS.)

All across this Arctic Ocean region, melt ponds and widening polynyas now abound in the ridiculously warm airs. In the satellite shot above, the tell-tale bluish tint of the ice reveals a plethora of these ponds expanding northward through the ESS and on toward the pole. A flush of hot water running into the Arctic Ocean from East Siberia’s rivers is melting the near shore ice. And a giant 80 mile wide gap of open water has now been torn into the ice of the Laptev Sea.
Record Extent Lows Continue to Worsen

The sudden Arctic heatwave and rapid related melt involvement of the ESS and Laptev regions of the Arctic Ocean is just the most recent melt spike in an Arctic Ocean that sees extent levels hitting new record lows with each passing day. As of June 2nd, the expanse of Arctic Sea ice only measured 10.37 million square kilometers. This is about 430,000 square kilometers below the previous daily record low set just last year and fully ten days ahead of the record sea ice melt year of 2012.
Arctic sea ice extent new record lows
(Arctic sea ice extent record lows continue for this time of year and threaten to plunge deeply below the 2012 line in coming days. Image source: JAXA.)

A coverage of sea ice that is now 42 days and 2.1 million square kilometers of sea ice loss ahead of an average melt year during the 1980s.
Here Comes the Greenland High

Extreme heat building into the Siberian side of the Arctic and record low sea ice extent measures are today being joined by yet another disturbing Arctic feature. For as of yesterday, a strong ridge of high pressure began to form over Greenland, the Canadian Archipelago and Iceland.
Greenland highs tend to increase temperatures over the enormous glaciers of that frozen island even as the clockwise circulation pattern of an anticyclone tends to shove sea ice out into the Barents and North Atlantic. The dominance of a Greenland High during both 2012 and 2007 is thought to have heavily influenced record end season sea ice melts during those years as well as the extreme Greenland surface melt spike during 2012.
(A high pressure ridge emerging over Greenland, Iceland and the Canadian Archipelago today is expected to strengthen this week — generating a high pressure gradient between warm storms developing over the Arctic Ocean and winds that threaten to increase the rate of ice transport out of the High Arctic and into regions of warmer water. Image source: Earth Nullschool.)

This week’s predicted ridge formation is not expected to bring with it a severe surface melt of Greenland. However, the clockwise winds driving sea ice transport may serve as yet one more heavy blow to the already greatly weakened ocean ice. Pressures later this week are expected to rise to 1040 mb over Greenland. And strong winds running between powerful warm storms expected to form in the Kara and Central Arctic are predicted to rise to near gale force north of Greenland — generating a risk of a very vigorous ice loss from the near polar zone as floes are driven into warm Barents and North Atlantic waters.
In context, the combined severe record sea ice lows and emerging weather conditions represent a seriously bad state for Arctic sea ice. One with a high risk of continued further extreme losses and new daily record lows for at least the next seven days.
Hat tip to Greg
Hat tip to Cate
Hat tip to DT Lange

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