US GEOLOGICAL SURVEY / SCIENCE PHOTO LIBRARY US GEOLOGICAL SURVEY / SCIENCE PHOTO LIBRARY
Glacial retreat. Image 1 of 2. People standing outside of an ice cave on Boulder Glacier, Glacier National Park, Montana, USA, in 1932. Glaciers are large, slow-moving expanses of ice, formed from compacted layers of snow. They are sensitive to climate change and in recent years most have retreated dramatically. See image E235/379 for an image taken in 1988 which shows the extent of glacial retreat in 50 years.
Model release not available. Property release not required.