How Science Works | SolveClimate.com

James Hansen on How Science Works | SolveClimate.com: "Our understanding of the Earth’s climate, in particular, depends foremost on the Earth’s history: how past climate changed in response to changing boundary conditions. I rate observations of ongoing climate change and processes today, processes on the ice sheets, in the oceans, etc., as the second most important source of knowledge about climate change. Climate models rate only third, in my opinion. Models are a tool that helps us understand the other two, i.e., climate history and on-going climate phenomena. Models are a representation of reality, one that helps us combine different factors, evaluate relative importance, and try to understand interactions."