Monday, July 20, 2009

'Motion picture' of past warming paves way for snapshots of future climate change

MADISON - By accurately modeling Earth's last major global warming - and answering pressing questions about its causes - scientists led by University of Wisconsin-Madison and National Center for Atmospheric Research climatologists are unraveling the intricacies of the kind of abrupt climate shifts that may occur in the future.

"We want to know what will happen in the future, especially if the climate will change abruptly," says Zhengyu Liu, a UW-Madison professor of atmospheric and oceanic sciences and director of the Center for Climatic Research in the Nelson Institute for Environmental Studies. "The problem is, you don't know if your model is right for this kind of change. The important thing is validating your model."

To do so, Liu and his colleagues run their mode back in time and match the results of the climate simulation with the physical evidence of past climate.

Starting with the last glacial maximum about 21,000 years ago, the team simulated atmospheric and oceanic conditions through what scientists call the Bølling-Allerød warming, the Earth's last major temperature hike, which occurred about 14,500 years ago. The simulation fell in close agreement with conditions - temperatures, sea levels and glacial coverage - collected from fossil and geologic records.

To read full article, go to UW-Madison News.
To learn more about the images, go to University Communications.