The climate has always been in a state of change. There used to be mile high glaciers over southern Wisconsin thousands of years ago. The earth's climate changed, the glaciers receded and mankind had nothing to do with that global warmup. We do have some effect on weather and climate, but to what extent is a guess. IMHO, most of this hype is driven by politics, personal agendas and grant money. They can't predict weather accurately beyond tomorrow (if even that far), not sure how they can say what things will be like in 10, 20, 50 years.