Climate change communication expert Anthony Leiserowitz explains why climate change gets the silent treatment, and what we should do about it.

A climate change communication expert describes his efforts to galvanize communities over what’s arguably the greatest single threat facing humanity.

From Portland to Philadelphia, city mayors are addressing climate change on their own turfs.

Annie Leonard, director of The Story of Stuff, says reusable water bottles and canvas shopping bags are not enough.

A climate scientist explains that small changes in global temperature are comparable to small changes in body temperature -- both hosts get very sick.

Learn ways to make a difference in your own community on behalf of the planet.

Data from 11 of the past 12 months indicates a record-breaking 2012, but will climate coverage also warm up?

This year's UN Climate Summit in Doha, Qatar represents another lost opportunity for global action to reduce carbon emissions and slow global warming.

The Shock Doctrine author Naomi Klein joins Bill to discuss hurricanes, climate change and democracy.

The author and activist says the purest test for Obama will be the Keystone Pipeline.