Global Warning

Environmental refugees. Shore-line relocations. These could be buzz words in the next 50 years, warn some people. And it's time to start planning, they say.

Today, the Kyoto Accords go into effect without the United States onboard. More than one hundred and forty countries have signed onto the U.N.-backed treaty, which requires cutting back on carbon dioxide emissions or "greenhouse gases."

Hear a conversation about expanding the response to global warming.

Guests:

Andrew Revkin, environmental reporter with The New York Times;
Mark Hertsgaard, author of "Earth Odyssey: Around the World in Search of our Environmental Future";
Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research;
John Walsh, Professor of Climate Change at the University of Alaska at Fairbanks.