NOAA's National Centers for Environmental Information
Northern Hemisphere Snow Cover Extent
| December 2023 | Snow Cover Extent | Anomaly 1991-2020 | Trend per decade | Rank (58 years) | Record | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| million km² | million mi² | million km² | million mi² | million km² | million mi² | Year(s) | million km² | million mi² | |||
| Northern Hemisphere | 42.47 | 16.40 | -1.80 | -0.69 | +0.27 | +0.10 | Largest | 48th | 2012 | 46.85 | 18.09 |
| Smallest | 11th | 1980 | 37.44 | 14.46 | |||||||
| North America | 14.94 | 5.77 | -1.96 | -0.76 | +0.07 | +0.03 | Largest | 57th | 2009 | 18.27 | 7.05 |
| Smallest | 2nd | 1980 | 14.56 | 5.62 | |||||||
| Ties: 1979 | |||||||||||
| Eurasia | 27.53 | 10.63 | +0.17 | +0.07 | +0.20 | +0.08 | Largest | 18th | 2002 | 29.70 | 11.47 |
| Smallest | 41st | 1980 | 22.88 | 8.83 | |||||||
Data Source: Global Snow Laboratory, Rutgers University. Period of record: 1966–2023 (58 years)
The Northern Hemisphere snow cover extent for December 2023 was 42.47 million square kilometers (16.40 million square miles), which was 1.8 million square kilometers (690,000 square miles) below the 1991–2020 average.
This ranked as the 11th-smallest Northern Hemisphere December snow extent on record.
The North America and Greenland snow cover extent for December was 14.94 million square kilometers (5.77 million square miles), which was 1.96 million square kilometers (760,000 square miles) below the 1991–2020 average. This ranked as the third-smallest December snow cover extent for the region.
Above-average December snow cover extent was observed from portions of the Alaskan Panhandle into the central Rockies as well as across parts of eastern Canada. Below-average snow cover extent was observed across much of the western U.S. and from the Canadian Rockies into the central Plains and from the Great Lakes into the Northeast.
Snow cover extent over Eurasia in December was 27.53 million square kilometers (10.63 million square miles), which was 170,000 square kilometers (70,000 square miles) above the 1991–2020 average. This was the 18th-largest December Eurasian snow cover extent on record.
Most of northern Europe, Mongolia, and northeastern China had above-average snow cover extent this month. Much of the UK and from central Europe to central Asia experienced below-average snow cover extent for December.
Sea Ice Extent
The sea ice extent data for the Arctic and Antarctic are provided by the National Snow and Ice Data Center (NSIDC) and are measured from passive microwave instruments onboard NOAA Satellites. The sea ice extent period of record is from 1979–2023 for a total of 45 years.
| December 2023 | Sea Ice Extent | Anomaly 1991-2020 | Trend per decade | Rank (45 years) | Record | ||||
|---|---|---|---|---|---|---|---|---|---|
| million km² | million mi² | Year(s) | million km² | million mi² | |||||
| Northern Hemisphere | 12.00 | 4.63 | -3.23% | -3.39% | Largest | 36th | 1982 | 13.64 | 5.27 |
| Smallest | 9th | 2016 | 11.46 | 4.42 | |||||
| Southern Hemisphere | 8.67 | 3.35 | -16.63% | -0.58% | Largest | 43rd | 2007 | 11.98 | 4.63 |
| Smallest | 2nd | 2016 | 8.28 | 3.20 | |||||
| Globe | 20.67 | 7.98 | -9.38% | -2.15% | Largest | 43rd | 1988 | 24.69 | 9.53 |
| Smallest | 2nd | 2016 | 19.74 | 7.62 | |||||
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2023 (45 years)
December 2023 global sea ice extent ranked second lowest on record for the month at 20.67 million square kilometers (7.98 million square miles). December 2016 holds the record for smallest December sea ice extent on record (19.74 million square kilometers or 7.62 million square miles).
The Arctic sea ice extent for December 2023 ranked ninth smallest in the satellite record at 12.00 million square kilometers (4.63 million square miles). This was 400,000 square kilometers (160,000 square miles) below the 1991–2020 average.
Sea ice extent was below average in the Baffin and Hudson Bays, and the Barents, and Bering Seas. The central Arctic Ocean and the Chukchi Sea had near-normal extents for December. The Greenland and Kara seas as well as the the Sea of Japan (East Sea) and Sea of Okhotsk had slightly above-average sea ice extent for December.
The December 2023 Antarctic sea ice extent ranked second lowest on record at 8.67 million square kilometers (3.35 million square miles), or 1.73 million square kilometers (670,000 square miles) below the 1991–2020 average. This was about 390,000 square kilometers (150,000 square miles) above the record-low December from 2016.