JUDY WOODRUFF:

Last month, on the anniversary of Earth Day, President Barack Obama visited Florida's Everglades to highlight one of biggest threats from climate change: the rise in sea level that's already impacting one of the unique natural habitats in all the world.

The consequences aren't just to the hundreds of species of animals and plants that for centuries have called the Everglades home. It's to the economy and way of life for millions in South Florida who depend on the vast and teeming watershed once dubbed the "river of grass."

Special correspondent Mike Taibbi touched down on that great river to get a current assessment of its health and prospects.

This story comes to the NewsHour from WNET and the team that produces PBS NewsHour Weekend.