Dirty water and contaminated fish in the Chesapeake Bay and its tributaries pose a public health threat, but spotty monitoring and tourism industry worries can block the public from learning the full picture, health experts say.

Summer nights are getting hotter across parts of the United States, a trend that some scientists tie to global warming.

Hundreds of deaths caused by volcanic leaks of carbon dioxide are worrying experts seeking ways to bury industrial emissions of the gas as part of an assault on global warming.

Conservative Christian broadcaster Pat Robertson said Thursday the recent heat wave was the most convincing evidence ?in a long time? that global warming exists.

NASA scientists have joined the search for the elusive ivory-billed woodpecker, long thought to be extinct but recently sighted in Arkansas.