Heatwave on the Kara Sea in Siberia

A Siberian Heat Wave is Breaking Kara Sea Ice In March, So is it Time to Start Thinking about Hot Arctic Rivers?

Robertscribbler,

20 March, 2014

There’s a heatwave in Dickson, Russia today. But if you were standing on the shores of this port city on the Kara Sea in the far north, you might not realize it. The forecast high? 29 degrees Fahrenheit. (this is 1.6C - SMR)

Dickson is located about 500 miles north of the Arctic Circle and 1,000 miles south of the North Pole. To its west is Novaya Zemlya, a sparely inhabited and typically frozen island between the Kara and Barents Seas. To its east is Siberian Khatanga and Severnaya Zemlya an island system that, until 2005, sat in a pack of Arctic sea ice so dense and resilient, it was once possible to ski from Severnaya all the way to the North Pole even at the height of Northern Hemisphere summer. No more. The sea ice is now but a thin and wrecked shadow of its former glory.

Ask any resident of this, typically frigid, coastal town and they’ll tell you that today it’s abnormally warm, even hot for this far-north locale. For the average high for this day in Dickson is about 1 degrees Fahrenheit. Typical daily highs of 29 degrees (F) don’t normally appear in Dickson until mid-to-late June.

So, in essence, summertime has arrived in Dickson in March and there we see temperatures that are a shocking 28 degrees Fahrenheit above average. Human caused climate change at its most brazen. But we haven’t seen a thing yet…

As we can see in the map below, Dickson is but one location sitting beneath a vast and spreading Siberian and Arctic heatwave:

(Global temperature anomaly map for March 20, 2014 shows world temps +.65 C above the, already hotter than normal, 1979-2000 baseline and Arctic temps at +3.12 C. Note the large heat pool over Siberia. Image source: University of Maine.)

A heatwave extending from the Pacific Ocean in the east to the borders of Mongolia and China in the south. From Surgut in the west and on deep into the Arctic Ocean’s Laptev and Kara Seas in the far north. And it is vast, covering an area roughly 2,000 by 2,000 miles at its widest points. But the heatwave is not disassociated from other high temperature anomalies. It flings a wide outrider over the Beaufort Sea and the Bering Strait. And it sits in a broad flood of warmer than average air riding over Europe, the Middle East and Asia.

This Jet Stream entrained warm air feeds the heatwave even as pulses of much warmer than normal air rise up from the deserts of Western China over Mongolia and up into Russia to give it an added kick. The connecting pattern is a high amplitude Jet Stream wave surging past the Arctic Circle and deep into the Arctic Ocean. It is the kind of high amplitude pattern that, over recent years, has been implicated in so many extreme Arctic heat invasions and related severe weather events.

Temperatures in the far north of this hot zone range from 10 to over 36 degrees Fahrenheit above average for this time of year. For Siberia and the Arctic Ocean it is a heatwave of just below freezing and slightly above freezing temperatures. In other words — what, until recently, used to be summer-like conditions.

Heat Wave Breaking up Ice in the Kara Sea

Such anomalous warmth is enough to put a heavy strain on sea ice. The ice freezes and melts at around 28 degrees F. So extended periods near or above this temperature can have an impact on ice integrity. The ice gets hit by warmer air even as it floats over warmer waters. It’s a kind of one-two punch that can be pretty devastating to sea ice integrity.

And we see just this kind of situation over the past two weeks in the region of the Kara Sea near Port Dickson.

Normally, this frigid ocean zone is covered in a stable sheet of ice called land fast ice. The ice is anchored to the land at various points and tends to remain solid due to reduced movement caused by grounding on the surrounding land features. When the land fast ice starts to go, it usually presages melt.

(Break-up of Kara sea ice and land fast ice. Top frame shows the Kara on March 7, bottom frame shows break-up visible on March 17. Note that cloud covers a portion of both images and that the March 20 image — the most recent — is too obscured by cloud for detailed analysis. Image source: Lance-Modis)

With the recent influx of much warmer than normal air from the south, this is exactly what we see. A widespread breaking up of Kara sea ice and of even the more resilient features fixed to surrounding lands and islands. And as you can see in the lower frame image, the break-up is quite extensive and dramatic.

The current warm pulse is expected to last for the next few days before shifting back to Svalbard by early to mid next week. Meanwhile, overall Arctic temperatures are expected to remain between 2.5 and 5 C above the, already warmer than normal, 1979 to 2000 average all while a trend establishes that continues to feed warm air pulses up over Asia and into the Arctic Ocean zones of the Kara, Laptev and East Siberian Seas.

Abnormal warmth gathering over the continents in this way can cause both early melt and large flushes of warm meltwater into the Arctic Ocean. An issue that is specially relevant due to recent NASA studies of another section of the Arctic Ocean — the region north of Canada and the Mackenzie River Delta called the Beaufort Sea.

Warm Rivers Heat the Arctic Ocean, Melt Sea Ice

The NASA study found that large pulses of warm water from continental rivers are a strong mechanism for transporting heat into the Arctic and, over recent years, are one of many factors resulting in the sea ice’s rapid recession.

(Heat flux from Canadian Mackenzie River into the Beaufort Sea during recent melt years. The first image shows sea surface temperatures on June 12 of 2012 before the Mackenzie River discharged and on July 5, 2012 after. Note the ocean surface water temps rising by as much as 10 C between frames. Image source: NASA.)

The NASA study found that large heatwaves warmed the continents and that this caused continental rivers to disgorge warm water into an already warming Arctic Ocean. The findings showed significant contributions from warm rivers to rising sea surface temperatures and sea ice melt during recent Arctic summers including the record melt year of 2012.

As the Arctic experiences increasing pulses of summertime temperatures during late winter and into spring, it is likely that warm water discharge and overall warmth will play a role at the transition between sea ice freeze and melt season. And this thought brings us back to Russia which appears to be stuck in the abnormally warm pattern covered above. A pattern that, should it continue to flicker and swell, may well bring a surge of warmer than usual water into the Kara, Laptev and East Siberian Seas come later this spring and on into summer. A blow to sea ice that may well emerge but that we can ill afford.

Links:

The University of Maine

Lance-Modis

NASA: Warm Rivers Play a Role in Arctic Melt