There was a short period in which the earth temperatures rose. Thus appeared Al Gore and his doom and gloom theories. The scientists came up with theories on global warming and why. That is what they are paid to do. If they came up with a theory that said everything was alright, that is the end of their research and jobs. Politicians like Arnold Schwartzenegger and Barrack Obama tied their theory into policy. It is an expensive, policy at that. Now that the temperatures have not gone up as they predicted, they are coming up with new theories.