To fix the ozone, manufacturers of fridges and other products replaced ozone-busting CFCs and HCFCs with HFCs. But now the U.N. is warning that HFCs do a number on the climate. In other words, the solution to the ozone problem could be creating a climate change problem.

Oh, and no one thinks that the world could agree to implement any international climate change treaty before 2020.

Plus, the U.S. is now saying that some developing countries need to chip in to the fund that's supposed to help developing countries adapt to climate change. Bootstraps, people!

Carl Pope, chairman of the Sierra Club, stepped down after 40 years with the organization, including 17 as executive director.

How much green guilt should your Thanksgiving meal incur?

Hundreds of millions of people travel the world each year on religious pilgrimages, and there's a growing interest in making them more green. Here's one example of how that works.