The extent and rate of melting snow has consequences for many different areas of the environment. In a special report from 2022, the Intergovernmental Panel on Climate Change concluded that glacial melt and ice sheet loss are now the dominant contributors to global mean sea level rise. Summer melting of the Greenland ice sheet has increased to a level unprecedented over at least the last 350 years. Antarctic ice loss is dominated by acceleration, retreat, and rapid thinning of major West Antarctic outlet glaciers, driven by melting of ice shelves by warm ocean water.

Water runoff from melting snowpack and glaciers, when combined with rainfall, can affect the timing and magnitude of river flows and significantly impact the risk of flooding events. However, snow melt also has some beneficial effects — billions of people worldwide rely on seasonal water runoff from snowpack and glaciers for irrigation and drinking water. The Indus Basin in Asia, for example, is the largest irrigation system in the world; snow melt from the Himalayan mountains is essential for rice production in the basin and contributes significantly to agricultural irrigation. Changes in snow melt can have major impacts on food production.

Our data combine imagery from NASA’s Earth-observing satellites and surveys collected on the ground to help researchers study snow melt and runoff. This information is vital for studies of topics like global warming, water cycles, and agriculture.