Snowmelt in the Northern Hemisphere has been starting progressively earlier. The trend has been especially obvious in most of the mountain ranges of the western United States. In Wyoming’s Fremont Lake Basin, for example, scientists have found that the snowmelt season now ends about 16 days earlier than it did from the 1970s through the 1990s. Snowmelt is a significant water source in the state. Changes in its timing affect agriculture and ecosystems and also contribute to earlier and more frequent wildfires. Watch the video to see a satellite’s view of changes in the region during the 2013 snowmelt season.