The Arctic melt

The Arctic Heatwave Hits Central Siberia Pushing Temperatures to 90 Degrees and Sparking Tundra Fires

(Fires Flare in Central Siberia As Temperatures Near 90 Degrees. Image source: Lance-Modis)

robertscribbler,

21 June, 2013

Today, a heatwave circling the Arctic set its sights on central Siberia. 

Temperatures soared into the upper 80s to near 90 degrees over a vast region of Siberian tundra, setting off pop-corn thunderstorms and sparking large, ominous fires reminiscent of the blazes that roared through this region during late June of 2012. Those fires were so large they sent a plume of smoke over the Pacific Ocean and blanketed valleys in western Canada.

Each individual fire in the above image hosts a plume of smoke about a hundred miles long. The fire to the far left, hosts a very long smoke plume of at least 350 miles in length.

You can see these soaring Siberian temperatures and related fires on the Arctic weather map below. Note the instances of 32 degrees Celsius temperatures (which is 89.6 degrees on the Fahrenheit scale).

(Siberian Heat. Image Source: Uni-Koeln)

If you look to the right side of the above map, you’ll see a large swath of pink spanning the Arctic from Norway all the way to the Pacific coastal region of Siberia. The most intense heat is located directly in the center of this zone where sporadic readings of 90 degree temperatures start to pop up. Fires are also shown on this weather map, indicated by a vertical black bar with a squiggly black line at the top.

Heatwave conditions also appear to have re-flared in Scandinavia where numerous instances of 80 degree + weather appear.

Alaska is in its ‘cool night-time’ phase. But even now, some locations in the interior are showing ‘lows’ of 70 degrees — which is hotter than usual highs for this time of year in that region.

Looking at the Jet Stream map for today, we see three anomalous pulses rising up over each of these regions.

(Image source: California Regional Weather Service)

The Siberian pulse rises just to the edge of the Arctic Ocean. The Scandinavian pulse hits the top of Norway and Sweden. Meanwhile, the Alaskan pulse rides all the way up into the Beaufort and Chukchi Seas.

Jet Stream waves should not penetrate so far into the Arctic. It is a situation facilitated both by eroding sea ice and by loss of snow cover during spring and summer. As of May, both sea ice volume and Northern Hemisphere snow cover were the third lowest on record. Back in September of 2012, Arctic sea ice hit a record low volume that was 80% below levels seen in the early 1980s.

This mangling of the Jet Stream has also been implicated in a number of severe weather events (spawned by blocking patterns associated with large waves in the Jet Stream) including the extreme European Winter and Spring of 2013, the US Drought of 2012-2013, Hurricane Sandy, and, now, various heat-waves striking the Arctic.

Links:

Lance-Modis

Uni-Koeln

California Regional Weather Service

Dr. Jennifer Francis Explains the Extreme Jet Stream

Smoke From Massive Siberian Fires Seen in Canada

Barrow, Alaska: Heatwave Hosts Early Sea Ice Break-up

robertscribbler,

21 June, 2013

(Image source: Barrow Ice Cam)

Sea ice break-up, characterized both by melt and off-shore movement of surface ice, has now occurred off Barrow, Alaska. The event usually happens around July 8th. Since break-up was confirmed by visual yesterday, we are about three weeks early. If you want to see the video of off-shore ice breakup and movement, you 

can view it here.

Satellite images provided by Lance-Modis shows break-up and off shore ice motion between the days of June 19 and June 20.

(Image source: Lance-Modis)

Here’s the image of Barrow just as sea ice is starting to break up on June 19th. Barrow is located on the point of land near the lower left-hand portion of the image. Now, note how open water expands as ice shifts away in the second image below:

(Image source: Lance-Modis)

This early ice break-up off Barrow came in conjunction with a powerful Alaskan heatwave that sent temperatures in some places to the high 90s. Barrow didn’t experience the same extremes of temperature, but it did see highs in the 50s and 60s on some days. When temperatures usually hit highs around 39 degrees during this time of year, consistent highs in the mid 40s to the mid 60s is a heat-wave. And that’s what we’ve seen for more than a week now. Today’s high for Barrow is supposed to top off at around 50 degrees.

Barrow may soon see ice-free seas as a rapidly expanding melt front advances through the Chukchi and into the Beaufort Sea over the coming days. This region of melt hosts much higher than above average water temperatures that were likely fueled by the recent Alaskan heatwave which pumped air temperatures in Prince William Sound above 90 degrees. A pulse of warmer water feeding from Alaska’s estuaries and into this growing body of ice free area is likely fueling above average water temperatures.

(Image source: Lance-Modis)

Expect a large area from Barrow to Wrangel Island to be vulnerable to rapid melt as this front of warmer ocean water advances northward. The image above shows this region of open water advancing along the north coast of Alaska and into a region of the Beaufort and Chukchi Seas off shore on June 21rst.