This is not really a legal topic, but still:
and it's snowing in New Jersey and Pennsylvania. Everywhere Al Gore goes, it seems to hit record low temperatures.
The media proclaims that it's perfectly obvious that climate change is happening and will be irreversible imminently. However, people still disagree, and not just crackpots- it's respected scientists.
The climate change issue isn't all that different from legal issues: reasonable people can disagree. There isn't a definite answer to this one, because the forces at work are too complex to understand completely. We shouldn't act like we do understand them.
You can read lots of other blog articles about climate change at http://www.blogactionday.org.