NOAA's National Centers for Environmental Information
Northern Hemisphere Snow Cover Extent
| April 2024 | 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 | 27.81 | 10.74 | -2.12 | -0.82 | -0.41 | -0.16 | Largest | 58th | 1979 | 34.61 | 13.36 |
| Smallest | 1st | 2024 | 27.81 | 10.74 | |||||||
| North America | 11.95 | 4.61 | -1.22 | -0.47 | -0.07 | -0.03 | Largest | 56th | 1975 | 15.08 | 5.82 |
| Smallest | 3rd | 2010 | 11.02 | 4.25 | |||||||
| Eurasia | 15.86 | 6.12 | -0.90 | -0.35 | -0.34 | -0.13 | Largest | 49th | 1981 | 20.69 | 7.99 |
| Smallest | 10th | 2014 | 14.77 | 5.70 | |||||||
Data Source: Global Snow Laboratory, Rutgers University. Period of record: 1967–2024 (58 years)
The Northern Hemisphere snow cover extent for April 2024 was 27.81 million square kilometers (10.74 million square miles), which was 2.12 million square kilometers (820,000 square miles) below the 1991–2020 average.
This ranked as the smallest Northern Hemisphere April snow extent on record. The downward linear trend in April Northern Hemisphere snow cover extent over the 58-year record equates to an average reduction of 41,000 square kilometers (16,000 square miles) of snow cover extent per year.
The North America and Greenland snow cover extent was 11.95 million square kilometers (4.61 million square miles), which was 1.22 million square kilometers (470,000 square miles) below the 1991–2020 average. This ranked as the third smallest April snow cover extent on record for North America, and contrasted sharply with last April's snow cover extent of 13.92 million square kilometers (5.37 million square miles). Although the snow-covered area was above average in the western U.S., below-average April snow cover extent was present across most of North America. Small areas of above-average snow cover extent are visible in parts of the Rocky Mountains, the Sierra Nevada mountains, and areas south of Hudson Bay, Canada.
Snow cover extent over Eurasia in April was 15.86 million square kilometers (6.12 million square miles), which was 900,000 square kilometers (350,000 square miles) below the 1991–2020 average. This was the 10th-smallest April snow cover extent on record for Eurasia.
April snow cover extent was below-average in the Alps, across a large area from southwestern Russia to northern Kazakhstan, Kyrgyzstan, and far southeastern Russia, northeastern China and Japan. Above-average snow cover extent was present in parts of south-central Siberia, parts of Mongolia, and central China.
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 1979–2024 for a total of 46 years.
| April 2024 | Sea Ice Extent | Anomaly 1991-2020 | Trend per decade | Rank (46 years) | Record | ||||
|---|---|---|---|---|---|---|---|---|---|
| million km² | million mi² | Year(s) | million km² | million mi² | |||||
| Northern Hemisphere | 14.12 | 5.45 | -1.40% | -2.44% | Largest | 31st | 1982 | 15.47 | 5.97 |
| Smallest | 16th | 2019 | 13.43 | 5.19 | |||||
| Southern Hemisphere | 6.19 | 2.39 | -10.94% | 0.00% | Largest | 37th | 2015 | 8.37 | 3.23 |
| Smallest | 10th | 1980 | 5.40 | 2.08 | |||||
| Globe | 20.31 | 7.84 | -4.51% | -1.65% | Largest | 37th | 1982 | 23.19 | 8.95 |
| Smallest | 10th | 2019 | 19.15 | 7.39 | |||||
Data Source: National Snow and Ice Data Center (NSIDC). Period of record: 1979–2024 (46 years)
Globally, April 2024 sea ice extent was tenth smallest in the 46-year April record at 20.31 million square kilometers (7.84 million square miles). This was approximately 960,000 square kilometers (370,000 square miles) less than the 1991–2020 average, but well above the record low April extent of 19.15 million square kilometers (7.39 million square miles) set in 2019.
The average Arctic sea ice extent for April 2024 was the 16th smallest in the satellite record at 14.12 million square kilometers (5.45 million square miles). This was approximately 200,000 square kilometers (80,000 square miles) below the 1991–2020 average, and the greatest April sea ice extent since 2013.
April sea ice extent was below average in the Gulf of Saint Lawrence and Sea of Japan. It was well below average in Baffin Bay and the Sea of Okhotsk, which had their fourth (tied) and second lowest April sea ice extents on record, respectively. Sea ice extent was near to slightly above average in the Greenland Sea and Barents Sea.
The average Antarctic sea ice extent for April 2024 was the tenth smallest on record (6.19 million square kilometers or 2.39 million square miles), approximately 760,000 square kilometers (290,000 square miles) below the 1991–2020 average. This year's April extent was approximately 700,000 square kilometers (270,000 square miles) greater than April 2023.