BREMEN, Germany, June 25 (UPI) -- Heat transferred by ocean currents may cause abrupt global temperature changes, not global warming caused by greenhouse gases, German researchers said.
Measurements taken by scientists at the University of Bremen show new data from Chile is consistent with data from Antarctic ice core samples, countering earlier evidence that climate changes in the Northern and Southern hemispheres occurred in synchronization.
"You can make the climate cool in certain places just by redistributing the heat through changes in ocean currents, atmospheric circulation or both," Jean Lynch-Stieglitz, a professor at the Georgia Institute of Technology, said in a statement.
The researchers believe warm water flowing from the Southern Hemisphere gives up its heat when it enters the North Atlantic. Cool water then sinks and flows back south because it is denser, accounting for different climate changes.
Previous data taken in southern Chile and New Zealand, along with pollen samples, suggested the climate changes in the Southern hemisphere occurred at the same time as those in the Northern hemisphere.
