NOAA's National Centers for Environmental Information
NH Snow Cover Extent
| November 2020 | Snow Cover Extent | Anomaly 1991-2020 | Trend per decade | Rank (55 years) | Record | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| million km² | million mi² | million km² | million mi² | million km² | million mi² | Year(s) | million km² | million mi² | |||
| Northern Hemisphere | 35.97 | 13.89 | +0.92 | +0.36 | +0.48 | +0.19 | Largest | 12th | 1993 | 38.60 | 14.90 |
| Smallest | 45th | 1979 | 28.28 | 10.92 | |||||||
| Ties: 2017 | |||||||||||
| North America | 14.38 | 5.55 | +0.51 | +0.20 | +0.21 | +0.08 | Largest | 13th | 2018 | 15.72 | 6.07 |
| Smallest | 43rd | 1979 | 11.48 | 4.43 | |||||||
| Eurasia | 21.59 | 8.34 | +0.41 | +0.16 | +0.27 | +0.10 | Largest | 17th | 1993 | 24.13 | 9.32 |
| Smallest | 39th | 1979 | 16.80 | 6.49 | |||||||
Data Source: Global Snow Laboratory, Rutgers University. Period of record: 1966–2020 (55 years)
Snow cover extent for the Northern Hemisphere during November 2020 was above average at 35.97 million square km (13.89 million miles). This was the 12th largest November snow cover extent in the 55-year record. November 2020 marked the 12th consecutive November with above-average Northern Hemisphere snow cover extent. The Northern Hemisphere snow cover extent during the three-month season of September–November was 1.65 million square km (637,000 million square miles) was the 15th largest on record.
The North America snow cover extent for November 2020 was also above average at 14.38 million square km (5.55 million square miles), resulting in the 13th largest November snow cover extent on record. Above-average snow cover extent was observed across much of Canada and the northwestern contiguous U.S. Meanwhile, below-average November snow cover extent was observed across much of the northeastern and north-central contiguous U.S. Alaska and Canada had their seventh largest November snow cover extent on record, while the contiguous U.S. had a near-average November snow cover extent. November 2020 was North America's fourth consecutive November with above-average snow cover extent. During the three-month season of September–November, the North America snow cover extent was the fourth largest such period on record at 1.11 million square km (429,000 square miles) above average. Only the September–Novembers of 1969, 2014, and 2018 had a larger snow cover extent.
Above-average November snow cover extent was observed across southern Russia, Kazakhstan, Mongolia, and across parts of western and eastern China. Meanwhile, below-average November snow cover extent was observed across much of Europe, western Russia, and southern China. Overall, this was Eurasia's 17th largest November snow cover extent on record at 21.59 million square km (8.34 million square miles). This was the seventh consecutive November with above-average Eurasian snow cover extent. Eurasia's snow cover extent during September–November was near average.
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 1979–2020 for a total of 42 years.
| November 2020 | Sea Ice Extent | Anomaly 1991-2020 | Trend per decade | Rank (42 years) | Record | ||||
|---|---|---|---|---|---|---|---|---|---|
| million km² | million mi² | Year(s) | million km² | million mi² | |||||
| Northern Hemisphere | 8.99 | 3.47 | -11.34% | -5.23% | Largest | 41st | 1982 | 11.63 | 4.49 |
| Smallest | 2nd | 2016 | 8.66 | 3.34 | |||||
| Southern Hemisphere | 16.23 | 6.27 | +2.27% | 0.00% | Largest | 8th | 2013 | 16.87 | 6.51 |
| Smallest | 35th | 2016 | 14.22 | 5.49 | |||||
| Ties: 2006 | |||||||||
| Globe | 25.22 | 9.74 | -3.04% | -2.08% | Largest | 38th | 1980 | 27.51 | 10.62 |
| Smallest | 5th | 2016 | 22.88 | 8.83 | |||||
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2020 (42 years)
The November average Arctic sea ice extent was the second smallest for November on record at 1.71 million square km (660,000 square miles), or 16.0 percent, below the 1981-2010 average, according to analysis by the National Snow and Ice Data Center (NSIDC) using data from NOAA and NASA. This was only 127,000 square miles above the record low set in 2016. November 2020 marked the 21st consecutive November with below-average Arctic sea ice extent. According to the NSIDC, below-average sea ice extent was observed across the Barents, Kara, and Chukchi seas.
Antarctic sea ice extent during November 2020 was 230,000 square km (90,000 square miles) above average, tying with 1980 and 1984 as the 11th-largest November Antarctic sea ice extent in the 42-year satellite record. This was also the largest November snow cover extent since 2015.