This website is the digital version of the 2014 National Climate Assessment, produced in collaboration with the U.S. Global Change Research Program. For the official version, please refer to the PDF in the downloads section.
Lahars move rapidly down valleys like rivers of concrete. If you are on the floor of a valley that leads from a volcano and become aware of an oncoming lahar, seek high ground. Lahar is an Indonesian term that describes a hot or cold mixture of water and rock fragments that flows down the slopes of a volcano and typically enters a river valley.
Weighing up to 2,400 pounds and standing about six feet tall at the shoulder, bison appear ungainly, yet are surprisingly fleet. In fact, bison can move up to 35 miles an hour, rushing in to defend their young or when approached too closely by people. Their broad shoulders allow them to plow through deep snow, and their shaggy heads are made for pushing snow aside to reach the vegetation below.