Wyoming Core Study Part Of Detailed Study Of PETM (Last Major Carbon Release Before Holocene)
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Sixty million years ago the Earth was already at least a few degrees warmer than it is today. At that point, there was little or no ice at the poles, and alligators were probably swimming in areas where polar bears roam today. But 4 million years later (56 million years ago) the world was about to undergo major changein an event called the Paleocene-Eocene Thermal Maximum (PETM). During the PETM, massive amounts of greenhouse gases, probably in the form of methane that later oxidized to carbon dioxide, were spewed into atmosphere.
Scientists are still uncertain as to what had caused the release, but they do know that it happened in a short time periodprobably a few thousand years. This CO2 explosion is similar to the one being produced by people now, which is why it is of such interest to scientists.
"The amount of carbon released in the PETM is thought to be similar to if we burn all of our fossil fuel reserves," says Phillip Jardine, who is studying the effects of PETM on plants as part of the Bighorn Basin Coring Project (BBCP) in Wyoming. Together with the massive carbon release, the PETM is marked by another distinct featurea rise of 5-8 degrees Celsius in global temperatures, a rise scientists say would be catastrophic for human civilization today.
"The PETM is especially valuable to climate scientists to understand better how the climate system actually works, and especially how releasing carbon impacts on temperatures," says Dr. Jardine. "The PETM studies have shown the link between the two very nicely, with rapid shifts in both the carbon cycle and global temperatures." So, instead of trying to predict what happens when massive amounts of CO2 are released into the atmosphere, scientists can look at the past and see what actually did happen.
EDIT
http://news.mongabay.com/2013/0123-freydlin-petm.html