Glacier meltdowns amid global warming

To study the impact of global warming, Bruce Molnia, a research geologist at the U.S. Geological Survey, decided to take contemporary photographs of Alaskan glaciers from the exact spot where photographers captured images around the turn of the century. The above photograph shows the bottom end, or calving terminus, of Muir Glacier in June 1899.

Credit: U.S. Geological Survey

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