Seemorerocks: Record low winter Arctic sea ice

Arctic Heat Drives Sea Ice Back Into Record Low Territory At Top of Melt Season

(Record low sea ice cover on March 10, 2014 a time that typically features sea ice maximum. Note that all basins show sea ice area and extent below the, already lower than normal, 1979-2000 base-line. Image source: Climate Change Institute.)

Robertscribbler,

11 March, 2014

Abnormal, warm southerly winds at the lower and upper levels. More large heat pulses driven by high amplitude Jet Stream waves. Tropical heat launching into the Arctic Stratosphere over the Himalayas. Warm water upwelling from the rapidly heating ocean depths.

All conditions that continue to place the Arctic sea ice under a state of constant siege — winter and summer. All again doing their dangerous work in pushing the now critically weakened ice, once more to record low levels.

Under this state of ongoing assault, regions near Svalbard fell into rapid retreat as floes fractured over warming waters in the Bering Sea and west of Greenland. The result is the lowest measure of winter time sea ice area ever seen in any record for this day since Arctic observation began. Yet one more passing milestone in the vicious and rapid progression of human-caused climate change.

2011 Records Fall

According to reports from NSIDC and Cryosphere Today, Arctic sea ice area dropped to a record low of 12.95 million square kilometers on March 10 of 2014. It is a measure more than 2 million square kilometers, or an area roughly the size of Greenland, smaller than that seen during the late 1970s and breaking the previous record low, set just three years ago, by 150,000 square kilometers. Sea ice extent, meanwhile, had fallen to 14.5 million square kilometers, a measure roughly tied with the previous record low set in 2011 and also about 2 million square kilometers below area values seen during the late 1970s.

It is worth noting that the trend lines for both sea ice extent and area are well below previous trends for record low years 2007 (green below) and 2012 (pink below).

(March 10 Sea Ice Area showing record low for the day. Image source: Pogoda i Klimat. Data Source: Cryosphere Today.)

Melt Hot Spots: Ocean Zones Near Svalbard and Greenland

With the Aqua Satellite again cresting the Arctic, we can peer down through cloud and ice to see dark, open waters peeking through kilometer-wide cracks or dominating entire ocean zones during a very anemic peak freeze. With recent days bringing average Arctic temperatures in the range of 2.5 to 4.5 degrees Celsius above normal and with local spikes in the +20 degrees C above normal range, areas of visible retreat and fragility abound.

These heat spikes combined with strong southerly winds near Svalbard to drive a rapid, far-north, retreat of ice floes on March 9-11 into zones that previously saw open ocean only during summer time. This far northward invasion of dark, open water is the primary culprit of the new record low:

(Open ocean north and west of Svalbard on March 11, 2014. It is worth noting that Svalbard is about 600 miles from the North Pole. The Current sea ice edge, during a time when ice extent should be at its maximum, is now just 500 miles from the North Pole. Image source: Lance-Modis.)

A large region of northern Baffin Bay near Northwest Greenland and the Canadian Arctic Archipelago also showed extensive melt and open ocean zones during recent days.

Over past decade, this region has shown increasing susceptibility to warm ocean water upwelling near the Nares Strait with winter-time melting of northern extremities in Baffin Bay. But this year’s melt was particularly strong. An event that coincided with sea-bed earthquakes and anomalously high methane levels (1950 ppb+) in the region through mid-to-late February. It is possible that upwelling is both driven by warm water currents now filling up the Baffin deep water zone and by the somewhat energetic out-gassing of sea bed methane through faults and seeps.

It is worth noting that evidence of these seeps is based on satellite observation and very little in the way of comprehensive seabed methane assessment has been completed by the global scientific community, a gap in understanding that may well come back to haunt us as human-caused warming continues to put increased heat pressure on both deep and shallow ocean carbon stores.

(Fingerprints of warm water upwelling, sea-bed methane release? Extensive open water, cracked ice in North Baffin Bay, Nares Strait region during height of sea ice extent, 2014. Image source: Lance Modis.)

Heightened risk for record low year, total meltdown

The current record low status for end winter sea ice and the approach of El Nino, which tends to add heat to the European and Asian continents, results in an increased risk that new record lows for sea ice area, extent and volume may be reached by end of summer 2014. Both warm air and water flushing in from the continents have been implicated in large sea ice retreats during recent years and a rapid heating of the large land mass over Arctic Europe and Asia, along with a simultaneous warming of Alaska, should El Nino progress, may amplify both continental heat build up and heat transfer through river outflow into the Arctic Ocean Basin.

In addition, high temperature anomalies during late winter to early spring continue to suppress sea ice recovery late season. The result is that more open ocean is now available to absorb energy from the rising sun or to deliver that energy in the form of waves and currents to the greatly diminished ice pack. The one saving grace, if it can be viewed as such, is a minor, though likely temporary rebound in sea ice volume extending from late last year, likely bringing volume values into the range of 3rd or 4th lowest on record for March.

It is also worth considering that sea ice area trends show an ever-increasing possibility of a record melt year with melt rates similar to 2007, 2011 or 2012 enough to bring 2014 to new record lows.

(Sea ice area projections based on past trends. It is worth noting that the melt season has lengthened by nearly a month since 1979, the result being increasing volumes of ice lost from end of freeze to end of melt. Image source: Jim Pettit. Data Source: NSIDC.)

In any case, this combination of conditions generates a high risk of sea ice reaching new record lows in sea ice area, volume and/or extent come end of summer 2014 (60%). This prediction finds its basis in observed records of past melt seasons and in the fact that very few days remain for a potential late-season uptick in sea ice. If record low values hold and a late season rebound does not occur, it is worth considering this simple fact: each time sea ice reached a new record low maximum sea ice area since 2005, a new record area melt was achieved by end of summer. That said, not achieving a record low maximum is no guarantee of safety, as 2012 so starkly proved.

It is also worth considering that sea ice may be very close to tipping points and once thinned beyond a certain threshold will be unable maintain integrity. In such an event, warm, dark, increasingly mobile ocean waters eventually overwhelm an ice pack fighting for survival. We may well have seen the beginning of such a consequence during 2012 when powerful and energetic storms that would usually result in sea ice retention only served to hasten record losses. A warning that there are fewer and fewer conditions favoring summer ice retention as the Arctic energy balance is ever more forcibly shoved toward melt.

Given these potentials — the high likelihood for record low area at maximum, the ever-lengthening melt season, and the increasing fragility of ice come end-summer — it is worth considering the unexpected worst case: total sea ice loss or near total ice loss (less than 1 million square kilometers area) by end of summer 2014. At this point, given record low area conditions late in the freeze season, we will assess a slight uptick of total ice loss risk over the previous year from 10 to 15 percent — a somewhat increased risk that sea ice values reach near ice free levels during a catastrophic melt this summer (15%).

If an observed start to the melt season begins early and if melt rates rapidly steepen, we will likely reassess both the likelihood of new records at minimum and a potential ice-free end summer state in the face of increased risks. At this point, both measures are low confidence estimates based on trends analysis, observation of current unprecedented Arctic warmth, and continued fragile ice state conditions.

Links:

NSIDC

Climate Change Institute