The history of global warming begins in the early days of the earth. Some scientists have thought that a build up of methane gas is what truly killed the dinosaurs. We are fighting a global warming trend to this day. I believe that it is just the cycle of earth and it is the earths way of cleansing and starting over in some ways. The earth goes through many different cycles and ages. Seems like scientists today are just trying to stop the un avoidable. As I’ve said Global warming has been an ongoing process since Earth began it’s life millions of years ago.