If you don't already know about them, Coursera offers free
online classes on a variety of subjects - many at the university level. To find out more about Coursera, here's a link to their
About page.
I was perusing their offerings today and found the following:
Energy, the Environment, and Our Future taught by Penn State professor, Richard B. Alley who did research for the PBS series:
Earth, the Operator's Manual. The
class started Jan 6th but I signed up to receive notification when the next session comes out.
Here's a video intro to the course.