Previous posts showed 2020 Arctic Ice breaking the 15M km2 ceiling mid March before starting the Spring melt as usual later in the month. The graph above shows that the March monthly average has varied little since 2007, typically around the SII average of 14.7 Mkm2 +/- a few %. Of course there are regional differences as described below.
The graph above shows ice extent through March comparing 2020 MASIE reports with the 13-year average, other recent years and with SII. After exceeding the average the first half, extents fell off the last 10 days, principally due to melting in the Pacfic basins of Bering and Okhotsk.
The table below shows the distribution of sea ice across the Arctic regions.
| Region | 2020091 | Day 091 Average | 2020-Ave. | 2007091 | 2020-2007 |
| (0) Northern_Hemisphere | 14282630 | 14713851 | -431221 | 14158467 | 124163 |
| (1) Beaufort_Sea | 1070655 | 1070176 | 479 | 1069711 | 944 |
| (2) Chukchi_Sea | 963163 | 963149 | 14 | 966006 | -2844 |
| (3) East_Siberian_Sea | 1086324 | 1086066 | 258 | 1074213 | 12111 |
| (4) Laptev_Sea | 897668 | 895482 | 2186 | 867162 | 30506 |
| (5) Kara_Sea | 928986 | 916178 | 12808 | 908181 | 20805 |
| (6) Barents_Sea | 688659 | 648978 | 39681 | 469156 | 219503 |
| (7) Greenland_Sea | 709503 | 656533 | 52970 | 670061 | 39442 |
| (8) Baffin_Bay_Gulf_of_St._Lawrence | 1320493 | 439783 | -119290 | 1232093 | 88399 |
| (9) Canadian_Archipelago | 854282 | 852731 | 1552 | 849011 | 5271 |
| (10) Hudson_Bay | 1260152 | 1254854 | 5298 | 1229963 | 30189 |
| (11) Central_Arctic | 3248013 | 3235482 | 12531 | 3245424 | 2589 |
| (12) Bering_Sea | 484084 | 744587 | -260503 | 721969 | -237885 |
| (13) Baltic_Sea | 8975 | 65202 | -56227 | 45656 | -36682 |
| (14) Sea_of_Okhotsk | 753705 | 874501 | -120796 | 797516 | -43812 |
Overall NH extent March 31 was below average by 431k km2, or 3%. The bulk of the deficit is seen in Bering and Okhotsk seas, along with Baffin Bay. Everywhere else is slightly surplus, with the exception of the Baltic, which never froze completely this year.
I don’t know much about arctic ice and enjoy your reports.
Do you have data for the ice extents further back, and for how long have measurements been made?
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Thanks Jack, there’s lots of posts here under the category Arctic Sea Ice. For starters, try this one:
https://rclutz.wordpress.com/2015/10/04/ice-house-of-mirrors/
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Just what i wanted. It seems that ice has been steadily declining since the end of the lia: no surprise there!
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Jack, that’s true, and on top there is a quasi-60 year oscillation affecting extents. See:
https://rclutz.wordpress.com/2019/08/09/todays-arctic-ice-precedented-150-years-ago/
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Reblogged this on Climate Collections.
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