Arctic Calmer For Now, Slow Spring Melt Continues

The drama appears to have mostly subsided for now. An unprecedented cracking event that began in February and expanded through mid-March seems to have mostly paused. Brief openings revealing open water have mostly frozen over with thinner ice.

This is not to say that the Arctic is entirely quiet. Thick ice has continued to lift away from the CAA and Greenland, resulting in a spreading and thinning of ice in these regions. Ice shows rapid movement out the Fram Straight. Tantalizing hints of new cracks emerge. And a slow melt proceeds.

seaice.recent.arcticmar27

(Image Source: Cryosphere Today)

Cryosphere Today shows sea ice area dropping slowly to about 380,000 square kilometers below sea ice maximum. The current measure, 13.399 million square kilometers is the seventh lowest on record for this date and somewhat lower than the 2012 measure for today.

The smoothed NSIDC graph shows decline continuing in sea ice extent, with measurements of around 14.9 million square kilometers. This measure is now outside the -2 standard deviation range and shows continued slow decline. Sea ice extent has been hovering around 5th lowest on record for the past few days.

Cracks Mostly Stable, Though Fissures Appear More Pronounced Near North Pole

Major crack expansion seen in February and early March has abated over the past week. However, some features of interest do appear on recent satellite shots. A series of fissures can now be seen traversing the thick ice in a crescent moon pattern west of the North Pole and running up from Greenland and the CAA. These appear somewhat more pronounced than yesterday, though enhanced clarity may be from a better satellite shot. In any case, these fissures as well as the Beaufort cracks will bear watching over the coming days and weeks as spring season melt intensifies.

hrpt_dfo_ir_100mar27

(Image Source: Canadian Weather Office)

General Climate Conditions

Overall temperatures for the Arctic remain above average with warmer than normal temperatures concentrating around Greenland, Baffin Bay, and the Canadian Arctic Archipelago (CAA). A pool of above average temperatures also remains north of Siberia. Weather maps show high pressure continuing to dominate the central Arctic with a series of weak to moderate low pressure systems skirting the area of this high in the Bering, Northern Canada, and South of Svalbard. A strong low (970mb~) approaches Greenland, Iceland and England from the North Atlantic.

Though the central Arctic high still dominates, negative Arctic Oscillation values have fallen to around -3.8 from a peak of about -5.5 more than a week ago. Negative AO values are forecast to shift closer to zero come early April.

Overall, higher than average temps, what appears to be still fragile ice, still rapid ice mobility, and weather systems whittling away at the ice edge would still seem to favor slow ice melt over the next week. That said, we may experience a small bump in sea ice values as somewhat colder air briefly over-rides the current melting trend. Generally, though, seasonal forcing would tend to combine with the above factors to push for continued gradual melt.

Links:

http://nsidc.org/arcticseaicenews/

http://www.weatheroffice.gc.ca/data/satellite/hrpt_dfo_ir_100.jpg

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

http://arctic.atmos.uiuc.edu/cryosphere/

http://www.uni-koeln.de/math-nat-fak/geomet/meteo/winfos/arcisoTTPPWW.gif

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