Did you know that from the 60's to the 80's the big environmental scare was Global Cooling and the dire consequences we were going to face as a planet if we didn't do something soon? Then in the 80's the temperature stabilized and starting rising slightly to create a time of Global Warming. Hmmm...seems like a cycle.
A climatologist has a great article tracking the debate of Global Warming and even shows how the scientific method has been completely subverted in this political debate. His main point is that the earth is following cycles like it always has and will continue to do so no matter what we do as humans.