
Meltponds and leads in the Arctic ice cap show evidence of refreezing
Day 298, October 25, 2015 Arctic ice extent virtually matched 2014 on the same day. For the first time in 100 days, July 17, ice extent is again 8.5M km2. MASIE shows 8.47M compared to NOAA at 8.11M.
2015 has gained steadily the last 10 days at a daily rate of 181k km2. As a result, 2015 lhas reached a virtual tie, lagging behind only slightly.
The rate of ice recovery this year since minimum day 260 is 109k km2 per day, 11k greater than 2014, and the highest in the last decade, except for 2013 and 2008.
The BCE region (Beaufort, Chukchi, East Siberian) is now 105% of 2014 at this date. Most seas exceed 2014 at this date. The largest remaining differences are Barents and Kara, which melted early and have not yet recovered. CAA has recovered after the August 2015 storm and now exceeds last year, through the Central Arctic still lags behind.
From MASIE
Ice Extents | 2014298 | 2015298 | Ice Extent |
Region | km2 Diff. | ||
(0) Northern_Hemisphere | 8531378 | 8470311 | -61067 |
(1) Beaufort_Sea | 874812 | 1046413 | 171601 |
(2) Chukchi_Sea | 445204 | 436170 | -9034 |
(3) East_Siberian_Sea | 746853 | 786087 | 39234 |
(4) Laptev_Sea | 817198 | 897757 | 80559 |
(5) Kara_Sea | 774019 | 567237 | -206782 |
(6) Barents_Sea | 237519 | 13282 | -224237 |
(7) Greenland_Sea | 390963 | 430467 | 39504 |
(8) Baffin_Bay_Gulf_of_St._Lawrence | 168991 | 257335 | 88344 |
(9) Canadian_Archipelago | 775255 | 823421 | 48166 |
(10) Hudson_Bay | 63494 | 73546 | 10052 |
(11) Central_Arctic | 3232620 | 3137455 | -95165 |
Summary
The comparison with 2014 informs us whether this year will “bend the trend” of recovering ice extent since 2007, and by how much. The pace of refreezing this year is impressive and the end result remains to be seen. It seems unlikely that the previous two years can be overtaken this late in the calendar.
My guess: 2015 Average Annual extent will finish as the 3rd highest in the last 10 years, ahead of the years before 2013.
Still a Bronze Medal is not bad for a year that started with a lower March maximum, had the Pacific Blob melt out Bering Sea a month early, saw a negative AO most of the summer ensuring higher insolation and melting, and finally underwent a strong storm late August when ice edges were most fragile.