Glacier National Park is losing its iconic glaciers to a changing climate. In the mid-1800s, this Montana landscape was covered by 150 glaciers—today only 25 remain. To show the decrease in glacier size, scientists from the USGS Northern Rocky Mountain Science Center photograph the same areas where glaciers were photographed in the early 1900s. Dan Fagre, a USGS research ecologist, has been studying climate change in the park for more than 20 years. Fagre and his colleagues discuss what melting glaciers and climate change mean for the future of the park, which is expected to be nearly glacier free by 2030, based on present warming trends.