When it comes to elevation, the United States is a country of extremes. On one end of the spectrum, Alaska's Denali is the highest mountain in North America, rising to more than 20,000 feet above ...

New data shows that water levels in major reservoirs including Lakes Mead and Powell are well below average for this time of ...

A technique using satellites to create twice-yearly elevation maps of US mountain glaciers provides new insight into thinning of glaciers in the lower 48 states.