A new analysis of ice-core climate data, archeological evidence and ancient pollen samples strongly suggests that agriculture by humans 7,000 years ago likely slowed a natural cooling process of the global climate, playing a role in the relatively warmer climate we experience today.
A study detailing the findings is published online in a recent edition of the journal Reviews of Geophysics, published by the American Geophysical Union.
“Early farming helped keep the planet warm,” said William Ruddiman, a University of Virginia climate scientist and lead author of the study, who specializes in investigating ocean sediment and ice-core records for evidence of climate fluctuations.
A dozen years ago, Ruddiman hypothesized that early humans altered the climate by burning massive areas of forests to clear the way for crops and livestock grazing. The resulting carbon dioxide and methane released into the atmosphere had a warming effect that “cancelled most or all of a natural cooling that should have occurred,” he said.
That idea, which came to be known as the “early anthropogenic hypothesis” was hotly debated for years by climate scientists, and is still considered debatable by some of these scientists. >> Read the Full Article