At Start of 2015 Melt Season, Arctic Sea Ice is in a Terrible State

Strong Polar Amplification. With human-forced climate change, it’s normally something you’d tend to see during winter time. By spring, the increase in solar radiation in the Mid-Latitudes would tend to force a more rapid pace of warming there. The snow and ice cover, recently refreshed by winter, would be at highest annual albedo at winter’s end. That high albedo would create a warming lag from the upper Latitudes. The resulting increase in temperature differential would then tend to reinforce the Jet Stream — giving it a strengthening kick and providing the polar north with a kind of ephemeral haven. At least for a brief window during early spring time.

Not so with 2015. This Spring, the Jet has been a basketcase. A mess of meanders like a river finding its way through a wetland prior to joining the sea. Strong south to north flows have persisted over the North Atlantic and well into Western Siberia. These meridional patterns have repeatedly delivered heat into the Arctic — particularly through the oceanic gateway between Greenland and the Yamal region of Russia.

Unusually Warm Spring for The Arctic

For the past week, this pattern intensified and the result is a bulge of extreme heat extending on toward the North Pole in the broad zone between Greenland and Northwest Siberia:

21 h Thursday April 9 Arctic T Anomaly Map

In the above image, provided by Climate Reanalyzer, we find a classic polar vortex disruption type pattern (a rather odd event for April, as both polar amplification and vortex formation have both tended to fade by this seasonal period) in which the cold core is essentially ripped in half by warm air invading from the south. In this case, we see a massive warm air flood emerging from Eastern Europe, Western Russia and the North Atlantic riding up and over the polar zone across a warm frontal boundary. This greater warm air influx is joined with a lesser one emerging off the Ridiculously Resilient Ridge pattern off the US and Canadian West Coasts and flooding up over Alaska and the Mackenzie Delta region of Canada.

The cold cores are thus shoved aside. One has fled to a dubious haven over Eastern Siberia. The second has taken a stronger hold over Greenland. For the Greenland region, surface winds have encircled the new, displaced, cold pool, generating a temperature boundary that is sharply visible in the anomaly map. The dangerous weather-wrecking “Storms of My Grandchildren” Greenland melt and polar amplification pattern — featuring a Greenland cold pocket beside a meltwater-cooled North Atlantic zone surrounded by angrily warming regions.

High anomaly departures in the range of 15-20+ degrees C above average cover about 1/3 of the high Arctic region above 80 degrees North Latitude. Laptev, Kara, Barents and the Arctic Ocean proper are all included in the heat bulge. Temperatures in this zone today spiked to near or above the point at which sea ice melts at the surface (-2.5 C) with temperatures in the Kara in the 0 to -2 C range, temperatures in the Laptev in the -2 to -4 C range and temperatures within 100 miles of the pole hitting around -3.8 C. For this region, these are readings more typical to June or even July.

Record Low Start to Melt Season

The impacts to sea ice have been nothing short of unprecedented for early season melt.

In the extent measure we find that for the past month running we have been at or near new record lows. Over recent days, consistent with the strong surge of polar heat amplification, extent values have again plummeted past previous record low values. Dropping by more than 50,000 square kilometers for each day in the April 6-8 timeframe, the melt rate is exceedingly steep for this time of year. With April 8 achieving a new record low extent of 14,073,000 square kilometers — 95,000 square kilometers below the previous record low of 14,168,000 set in 2006.

Sea Ice Extent April 9

(Arctic Sea Ice Extent as recorded by NSIDC through April 9 of 2015. We are at the descending curve of the upper arc on the left in the image. The bottom dark blue line represents 2015 sea ice extent. The light blue and pink lines are 2007 and 2006 [previous record low years for springtime]. The upper dark blue line represents 1979 sea ice extent. The dotted green line represents 2012. Note how the 2015 line has consistently trended in record low range during the past month. Image source: NSIDC.)

As heat and sunlight build in this record low ice extent environment, greater stretches of dark, open water will trap more sunlight. This will tend to have a heat amplifying effect — pushing for greater ice losses as melt season gains traction. Weather trends will tend to have an impact as well. And Arctic Oscillation (AO) is expected to again hit a strongly positive level over the next couple of days — providing further melt pressure to sea ice already at record lows. Wind patterns have also tended to facilitate ice export through the Fram, Nares and Bering Straits this year. Given a predicted continuation of these conditions, the long term-trend seems to be melt-favorable through end of April.

Kara Melting Early, Beaufort Cracking Up

In the satellite shot the impacts of these much warmer than normal Arctic conditions are clearly visible. Particularly, the Kara Sea near Northwestern Siberia and the Beaufort are showing signs of melt stress and ice fragility.

For the Kara, melt is proceeding well in advance of typical seasonal thaw. Large polynyas have opened up even as the ice edge has retreated. Much of the ice in this zone appears broken, thin, and disassociated — making it vulnerable to both increasing solar radiation and to the periods of more intense warmth to come.

Kara Sea April 9

(The Kara Sea showing reduced sea ice coverage on April 9 of 2015. Image source: LANCE-MODIS.)

With 2015 showing a tendency for strong south to north air flows in this region, the Kara continues to be at risk of early melt through spring and into start of summer.

But perhaps more disturbing is an ongoing and widespread break-up of sea ice in the Beaufort. Starting in late March and continuing on through April, very large cracks have opened up throughout the Beaufort Sea. Given that air temperatures remain in a range cold enough to freeze surface water (-12 to -25 C), the resulting gaps have quickly frozen. However, this crack-up is occurring directly at melt season start. Warmth is building, the sun is at an ever higher angle, and the lower albedo cracks may well serve to capture more heat in an already vulnerable region. In addition, temperatures in the Mackenzie River Delta — a region that, when thawed, will dump above freezing water into the already broken Beaufort — are approaching the melt point (-4 C readings today and 0 C for widespread thaw).

Beaufort Breaking Up

(Large cracks and polynyas throughout the Beaufort Sea on April 10 of 2015. Left side of frame is somewhat covered by cloud, but a large polynya [partially frozen] is visible through the coverage. Image Source: LANCE MODIS.)

These cracks are very extensive and include multiple large breaks. A scene reminiscent of the winter 2013 break-up. But the current timing at melt season start is far more likely to enhance ice vulnerability as spring progresses toward summer. Also, the fragile behavior of this broad section of Beaufort ice illustrates how thin sea ice in this region has become even as it hints at the potential that warm water (which is increasingly prevalent at depth throughout the Arctic Ocean) may be upwelling to melt some of this sea ice from below.

Together, the warm air influx and very high temperature anomalies, the rapid melt at the edge zones, the record low extent levels, and the massive crack-up ongoing in the Beaufort all point to extreme sea ice weakness at the start of melt season. With weather patterns remaining neutral to melt-favorable over the next few weeks and with winds favoring export through the Fram, Bering and Nares, risks remain high that Arctic sea ice will remain in record low territory over the coming weeks. Sea ice fragility in certain regions, especially the Beaufort, also bear watching for possible unpleasant surprises.

Links:

Climate Reanalyzer

NSIDC

LANCE-MODIS

The Storms of My Grandchildren

The Arctic Ice Blog

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“Dramatic Thinning” — Arctic Sea Ice Enters Record Low Territory as Northern Polar Region Heats Up

The Arctic sea ice is melting. It is melting far more rapidly than ever expected.

This loss is measured in the form of square kilometers melted, in the form of ice thinned, in the form of new, blue water visible. Yet it is a loss beyond mere numbers and measures. A loss that has a profound impact to the Earth and its climate systems.

Weather patterns, the rate of warming in the Arctic, the rate of tundra melt, seabed warming, and carbon store release. The rate of glacial loss in Greenland. All are impacted by sea ice loss and related ocean warming.

And today, we mark another new record low. The most recent in a long series, with likely many more thinning ice days to come.

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Earlier this week there were indications that Arctic sea ice extent may begin exploring new record low values in the Wednesday through Friday timeframe. And the March 4 measure finds NSIDC values sliding below previous records for the date set just 8 years ago.

Ever since Monday, extent values have been falling by an average rate of 10,000 square kilometers each day. A steady progression of warm air fronts through the Barents coupled with well above average temperatures in the Bering and near Alaska region have generated heat pressure along the ice edge and well into the Central Arctic.

As of today, we have extreme temperature departures in the range of +20 degrees Celsius above average in the Barents northward through to the polar zone. From the Bering through Alaska and into the Southern Beaufort near the Mackenzie Delta departures are in the range of +5 to +20 C above average.

global surface temperature anomaly March 5

(Polar amplification seen ramping up today in the GFS model analysis provided by Climate Reanalyzer. Exceptional warming of +20 above average occurred in vulnerable sea ice edge regions as extent values dropped to new record lows. Image source: The University of Maine’s Climate Reanalyzer)

These two hot spots, together with another warm pool over Greenland have shoved the Arctic, as a whole, into the +2 C range. A rather high departure that is only forecast to worsen in the GFS model summary over the coming days.

The added warmth, wind, and waves in these ice edge regions drove these extent losses and now, as of Wednesday, values had fallen to 14,383,000 square kilometers. By comparison the previous record low for the day in 2006 was 14,411,000 square kilometers, so the new record is 28,000 square kilometers lower. An area approximately the size of the State of Maryland. 2011 now comes in as third lowest for the day at 14,451,000 square kilometers or 68,000 square kilometers above the 2015 value.

Go back 30 years and the contrast is even more stunning with 1979 extent values for March 4 at 16,514,000 square kilometers. This places the new record fully 2,131,000 square kilometers lower than sea ice extent measures for the same date 36 years ago. A total loss of ice coverage roughly equal to Greenland (2,166,000 square kilometers).

chart(2)

(Sea ice extent for March 5 of 2015 [bottom blue line] drops to record low levels in the NSIDC measure. The other record low years for the date — 2006 [pink] and 2011 [orange] — are provided for reference along with 1979 [top blue line]. Image source: National Snow and Ice Data Center.)

But given the current time of year, a period where ice at low levels has tended to rebound, and given the fact that we are facing growing warmth in key ice edge regions, there is risk that record losses will continue to mount over the coming days.

GFS forecast models show warm fronts continuing to advance along a very strong south to north wind pattern stretching across most of the Atlantic. A wind pattern that today pulls tropical air off the underbelly of a high pressure system just north of Jamaica, funnels this warm air north and eastward over the currents of the Gulf Stream, dumps the flow into a raging low pressure (at 950 mb) just south of Greenland which then shoves the flow into a gale raging north of Scandinavia and south of Svalbard. A strong warm frontal boundary following in the wake of the most recent warm air invasion that, yesterday, swept past the pole.

It’s a meridional pattern stretching from 20 North Latitude in the Tropical Atlantic all the way to 90 North Latitude at the pole. One that features a contiguous frontal boundary stretching from Yucatan Mexico to halfway between Svalbard and Iceland along a daisy chain of lows south and east of Greenland. A flow that is complicit in both melt along the borders of the Barents and ice thinning in the Kara and on past the 80 North Latitude line in the Arctic Ocean.

image

(Amazingly vast frontal system and meridional pattern stretching from the Gulf of Mexico and Caribbean, across the North Atlantic and on into the Arctic. Reference point at 55.6 N and 34.6 W shows storm force winds proceeding almost due south to north. Screen capture in real time at 2:51 PM EST March 5, 2015. Image source: Earth Nullschool. Data  Source: Global Forecast System Model.)

This fire hose of warm air pouring up from the Atlantic will intensify over coming days as it fills the bowl of the Barents with heat, which GFS is predicting will balloon northward over the pole. By Sunday the temperature departures are predicted to peak in an extreme +4 C for the entire Arctic.

Most of the heat fueling this departure will come from the warm air invasion over the Atlantic Ocean zone. A secondary, but also very intense temperature departure is predicted to emerge along the Jet Stream ridge pattern stretching to the Mackenzie Delta region. There temperatures will also show isolated spikes in the +20 C above the 1979-2000 average range.

For the sea ice, such departures are very bad timing — hitting vulnerable regions hard just prior to traditional melt season start and possibly developing a rather low launching pad for the 2015 melt season. As such, there is high risk for continuing and expanding record lows for sea ice extent over at least the next five days.

Arctic heat spike

(Global Forecast System Model surface temperature anomaly forecast for Sunday, March 8 shows polar amplification ramping up to an extraordinary +3.99 C for the entire Arctic. Note the extreme positive temperature departures in a very large zone north of the Barents and in the Central Arctic Basin as well as the somewhat smaller but still extreme area of much warmer than normal temperatures over the Mackenzie Delta region. Image source: The University of Maine’s Climate Reanalyzer.)

New Record Lows Amidst Dramatic Thinning

The most recent record lows and threat of these low measures deepening come amidst new scientific reports finding an ominous and extreme thinning of sea ice in the Central Arctic Ocean near the pole. The study found that between 1975 and 2012 Central Arctic Sea Ice thinned from 11.7 feet to 4.1 feet.

Such thinning represents a loss of fully 65 percent of the sea ice volume for the Central Arctic Ocean over this period. But yearly average sea ice thinning paled in comparison to losses seen during September. For that month, sea ice thickness plunged from 9.8 feet to merely 1.4 feet — a stunning drop of 85% over the 37 years of measurements.

Study Author Ron Lindsay of the Applied Physics Lab at UW notes:

“The ice is thinning dramatically. We knew the ice was thinning, but we now have additional confirmation on how fast, and we can see that it’s not slowing down.”

Axel Schweiger, a polar scientist and contributor to the UW study added:

At least for the central Arctic basin, even our most drastic thinning estimate was slower than measured by these observations.”

A 1.4 foot average sea ice thickness for September is very thin. Tissue paper thin when it comes to sea ice. And the 4.1 foot yearly average isn’t much better. A fragile skein vulnerable to the continued assault of elemental heat we keep driving into the Arctic. Given this major loss, noted fragility, and ongoing exploration of record low values, risks for blue ocean events in this region are on the rise.

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UPDATE: On March 5, 2015 new record extent lows deepened in the NSIDC measure. By that date extent measures had fallen another 25,000 square kilometers to 14,358,000. The drop deepens losses and widens the gap between 2006 (second lowest on record) and 2015 to 74,000 square kilometers — or an area roughly the size of South Carolina.

Conditions — major heat build up along the ice edge zones, especially in the Barents region — continue to favor suppressed and reduced sea ice levels over the coming days. Updates on this evolving sensitive situation near the start of melt season will continue.

Links:

National Snow and Ice Data Center

The University of Maine’s Climate Reanalyzer

Global Forecast System Model

Earth Nullschool

Arctic Sea Ice Thinning Dramatically

Arctic Sea Ice Flirts with New Record Lows

Hat Tips:

Scientific Hat tip to Ron Lindsay and Axel Schweiger

Scientific Hat tip to the UW applied Physics research team

The Arctic Sea Ice Blog

Kevin Jones

Colorado Bob

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