In fact, spring snow cover in the Arctic is disappearing even faster than summer sea ice. On average, however, despite variations in mid-winter snowfall, Northern Hemisphere snow is melting earlier in the year.
Overall, snow is declining in both the Eurasian Arctic and the North American Arctic, although just how far below average the snow extent is varies from month to month and region to region as a result of natural variability.
In the Arctic, snow cover extent, duration, depth, and water stored by the snowpack are all declining. Despite this yearly variability, the long-term spring snow cover trend in the Northern Hemisphere is negative. In different phases of these back-and-forth patterns, some regions receive abnormally large or small amounts of snow. Recognizable patterns of climate variability such as the El Niño-Southern Oscillation and the Arctic Oscillation can affect the amount of snow that falls each year. NOAA map, based on data and analysis by Rutgers Snow Lab. Most of the Northern Hemisphere has experienced declines in the number of snow-covered spring days over the past 5 decades.
(Only places that had snow in at least 25% of the years on record are included in the analysis). Places where snow-covered days declined by up to three days per decade are shown in brown places where snow-covered days increased by up to 3 days per decade are blue-green. Map of April–June snow cover trends across the Northern Hemisphere from 1972–2021 based on satellite observations of the number of days each location had snow on the ground each year.
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