How Did Global Warming Start?

Most scientists agree that man-made climate change, or global warming, began in earnest during the industrial revolution, which occurred between the 18th and 19th centuries. This occurred, they say, as a result of a large number of greenhouse gases released into the atmosphere. However, in 2008, researchers from the University of Wisconsin-Madison concluded that global warming began as many as 8,000 years earlier with the advent of agriculture and deforestation.