Contrary to popular opinion that global warming began with the Industrial Revolution, a new study by University of Wisconsin-Madison scientists has found that global warming began 5,000 to 8,000 years ago with large-scale agriculture production in Asia and extensive deforestation in Europe.
The introduction of rice cultivation and tree removal caused increases in methane and carbon dioxide according to the research conducted with supercomputers and climate models. Steve Vavrus, a climatologist at the University of Wisconsin, explains the study's conclusion, "I think that the take-home message is that this hypothesis shows that climates are extremely sensitive to small variations in greenhouse gases."