Ice Age Ended Abruptly, New Study Shows

The Earth’s climate abruptly warmed by 20 degrees or more to end an ice age 12,500 years ago, according to researchers whose findings may force a reevaluation of the history of dramatic swings in the planet’s climate.

James White, a climatologist at the University of Colorado in Boulder, said an analysis of new ice cores from Antarctica show that the south polar area went through a rapid temperature increase at the same time as the north polar region.

The warming 12,500 years ago came within a typical human lifetime. Such rapid shifts in the climate on a global basis would make it very difficult for humans to adjust, White said. Climate affects agriculture, energy use, transportation and population shifts, and rapid changes would make adjustment in these things more difficult.

White, co-author of a study to be published today in the journal Science, said the antarctic ice cores show a temperature increase of about 20 degrees Fahrenheit within a very short time.

Ice cores from Greenland, near the Arctic, show that at the same time there was a temperature increase of almost 59 degrees in the north polar region within a 50-year period, White said.

He said the findings “throw a monkey wrench into paleoclimate research and rearrange our thinking about climate change at that time.”

White said researchers need to look more closely at how the Earth’s climate slipped from an ice age that ended about 12,500 years ago and shifted into the current, more temperate climate.

The findings, he said, also increase the urgency for researchers to understand climate shifts because it appears they could be abrupt and happen all over the Earth at the roughly the same time.