Two Hot Spots Slow Arctic Ice Recovery November 2025
Figure 12. (a) Predicted 10 mb geopotential heights (dam; contours) and temperature anomalies (°C; shading) across the Northern Hemisphere averaged for 25 Nov to 29 Nov 2025. (b) Same as (a) except forecasted averaged from 05 Dec to 09 Dec 2025. The forecasts are from the 00Z 24 November 2025 GFS model ensemble.
The polar vortex is pronounced this year, resulting in warmer temperature over the Arctic ocean, and slowing the normal sea ice recovery. Dr. Judah Cohen at AER Arctic Oscillation blog provides information like the chart above.
After a pattern of solidly growing sea ice extent in October, a slowdown occurred in November, coincidental with the warm spots shown above. The graph below shows 2025 compared to the 19 year average (2006 to 2024 inclusive), to SII (Sea Ice Index) and some notable years.
According to MASIE. the average November adds ~2.5M km2 of sea ice extent, which is matched also by 2007. 2024 started below average, but gained steadily to close the gap. 2025 started at the same level, but the refreezing slowed down, ending November in deficit by 1.1M km2. SII shows even lower ice extents (the last two days not yet reported.)
The table below shows the distribution of ice in the Arctic Ocean basins, suggesting two places where ice recovery is lagging.
| Region | 2025334 | Day 334 Ave. | 2025-Ave. | 2007334 | 2025-2007 |
| (0) Northern_Hemisphere | 9784037 | 10880420 | -1096383 | 11009948 | -1225911 |
| (1) Beaufort_Sea | 1071070 | 1069623 | 1447 | 1058872 | 12198 |
| (2) Chukchi_Sea | 879082 | 791207 | 87875 | 687829 | 191253 |
| (3) East_Siberian_Sea | 1087137 | 1083943 | 3194 | 1082015 | 5122 |
| (4) Laptev_Sea | 897845 | 897824 | 21 | 897613 | 232 |
| (5) Kara_Sea | 565299 | 792107 | -226808 | 826319 | -261020 |
| (6) Barents_Sea | 28050 | 242740 | -214690 | 216525 | -188474 |
| (7) Greenland_Sea | 550413 | 539687 | 10726 | 618844 | -68431 |
| (8) Baffin_Bay_Gulf_of_St._Lawrence | 412284 | 664437 | -252153 | 708497 | -296212 |
| (9) Canadian_Archipelago | 854931 | 853431 | 1500 | 850249 | 4682 |
| (10) Hudson_Bay | 188797 | 543322 | -354525 | 751382 | -562585 |
| (11) Central_Arctic | 3037637 | 3193296 | -155659 | 3183072.72 | -145436 |
| (12) Bering_Sea | 145331 | 138776 | 6555 | 72644.62 | 72687 |
| (13) Baltic_Sea | 4226 | 4452 | -225 | 0 | 4226 |
| (14) Sea_of_Okhotsk | 58288 | 61277 | -2989 | 53052 | 5236 |
Overall ice extent was 1.1M km2 below average or 10%. About half the deficit comes from the European Atlantic basins, Kara and Barents seas. The other half is mostly from N. America’s Hudson and Baffin bays. Ice in these regions operate on the LIFO principle, last in and first out.
At this point in the year, Arctic ice has grown back to 65% of last March maximum with 2.5 months to catch up. AER suggests that things may shift again in December:
Figure 9. Forecasted surface temperature anomalies (°C; shading) from 05 Dec to 09 Dec 2025. The forecasts are from the 00Z 24 Nov 2025 GFS ensemble.
Figure 10. Forecasted snowfall (mm/day; shading) from 05 Dec to 09 Dec 2025. The forecasts are from the 00Z 24 Nov 2025 GFS ensemble.
Illustration by Eleanor Lutz shows Earth’s seasonal climate changes. If played in full screen, the four corners present views from top, bottom and sides. It is a visual representation of scientific datasets measuring ice and snow extents.
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