Must-see video (ironically funded by David H. Koch):

http://video.pbs.org/video/1700738538

CO² as a causative factor of global warming figures prominently throughout the video.

Lotsa good stuff in it.

First 20 minutes below (full is about 52 minutes):

Watch the full episode. See more NOVA.

There is a program you can use to record things live on you computer screen.  Peter Sinclair and other youtubers use it all the time, but I don't know what it's called. 

I think iTunes is regional as well.

Can't see Nova in the TV Channels and Studios list, just Nickelodeon and Nick Jr (in the Ns).