Public Release: 5-Dec-2016
During last warming period, Antarctica heated up 2 to 3 times more than planet average
Amplification of warming at poles consistent with today's climate change models
University of California - Berkeley
Following Earth's last ice age, which peaked 20,000 years ago, the Antarctic warmed between two and three times the average temperature increase worldwide, according to a new study by a team of American geophysicists.
The disparity - Antarctica warmed about 11 degrees Celsius, nearly 20 degrees Fahrenheit, between about 20,000 and 10,000 years ago, while the average temperature worldwide rose only about 4 degrees Celsius, or 7 degrees Fahrenheit -- highlights the fact that the poles, both the Arctic in the north and the Antarctic in the south, amplify the effects of a changing climate, whether it gets warmer or cooler.
The calculations are in line with estimates from most climate models, proving that these models do a good job of estimating past climatic conditions and, very likely, future conditions in an era of climate change and global warming.
"The result is not a surprise, but if you look at the global climate models that have been used to analyze what the planet looked like 20,000 years ago - the same models used to predict global warming in the future -- they are doing, on average, a very good job reproducing how cold it was in Antarctica," said first author Kurt Cuffey, a glaciologist at the University of California, Berkeley, and professor of geography and of earth and planetary sciences. "That is noteworthy and a confirmation that we know how the system works."
The situation today, with global warming driven primarily by human emissions of carbon dioxide from burning fossil fuels, is different from natural cycles, he said. The ability of the oceans to take up carbon dioxide cannot keep up with the rising levels of greenhouse gases in the atmosphere, which means carbon dioxide and global temperatures will continue to increase unless humans cut their carbon dioxide emissions.