Global warming as a theory goes back to the 19th century.

For a recent version, search James Lovelock, the Gaia Hypothesis and "Daisyworld." There were also Russian antecedents. It's a bigger development than a corporate conspiracy could achieve.

Pollution exists, but that is a completely separate issue.

Equally obviously, glaciers recede, but glaciers have receded before, there having been as many as nine ice ages.

The crucial question is whether the short-term changes we observe are merely oscillations such as have occurred many times in Earth's history, or whether they are the signs of a the onset of a unique, catastrophic change. I quite agree with Gnu to the extent that to judge events on the geologic time scale, you need much more time depth than pix from satellites will give you.--You'd need matching satellite photos from 10,000 BC to prove anything that way.

The other crucial question is to truly establish the mechanics of the theory. I have no idea whether this has been done; I'd say "Follow the Lovelock trail and test it ...."

In the meantime this is a more serious topic than whether we should bash bunny-huggers or not.

CC