The amount of snow that falls in a particular area directly influences both snow cover and snowpack, which refer to snow that accumulates on the ground (see the Snow Cover indicator and the Snowpack indicator). Some plants and animals also depend on snow and snowmelt for survival. 1 Many communities also rely on snow for winter recreation. Many people depend on snow to provide water when it melts in the spring, including millions of people in the western United States, where snowmelt provides 75 percent of the water supply. Snowfall is an important aspect of winter in much of the United States. A few regions have seen modest increases, including some areas near the Great Lakes that now receive more snow than in the past (see Figures 1 and 2). Parts of the Midwest have also experienced a decrease, particularly in terms of the snow-to-precipitation ratio. The Pacific Northwest has seen a decline in both total snowfall and the proportion of precipitation falling as snow. Nearly 80 percent of the stations across the contiguous 48 states have experienced a decrease in the proportion of precipitation falling as snow (see Figure 2). One reason for the decline in total snowfall is because more winter precipitation is falling in the form of rain instead of snow. In addition to changing the overall rate of precipitation, climate change can lead to changes in the type of precipitation.Among all of the stations shown, the average change is a decrease of 0.19 percent per year. Total snowfall has decreased in many parts of the country since widespread observations became available in 1930, with 57 percent of stations showing a decline (see Figure 1).
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