One of the largest bodies of water in the United States, the Ogallala Aquifer, lies underground. Crucial to life in the U.S. Great Plains, it's one of many aquifers around the world under stress as water demands increase. Satellite data are now painting a richer picture of how these water stores are evolving.

Whether you’re looking at the next few weeks or the next few decades, many parts of the United States are likely to face the silent but devastating impacts of drought.

July 2012 promises to go down as the hottest month ever recorded in a number of U.S. locations.

Even if climate mitigation efforts succeed, current warming trends commit us to centuries of sea level rise.

The effort to improve air quality during the 2008 summer games enabled researchers to quantify the link between traffic and carbon dioxide.