IPCC

Worst-case planning never hurt anybody, and certainly not federal water projects that cost millions of dollars and could be easily undone by climate change and rising sea levels. A new policy now requires the U.S. Army Corps of Engineers to plan for future climate change when designing plans for flood control or other projects.

Yes, but probably not anytime soon. The Intergovernmental Panel on Climate Change estimates that the planet's average air temperature could warm by as much as 11.5°F by the end of the century. As a result, the world could be warmer than it was 55 million years ago, says Mark Lynas, author of Six Degrees, an analysis of hundreds of climate studies that reads like a nonfiction version of The Day after Tomorrow. Back then, the Canadian Arctic was as balmy as Florida and lousy with crocodile-like animals called champsosaurs.