Friday, April 29, 2011

Antarctic ozone hole affecting weather in tropics, new study says

The hole in the ozone layer over Antarctica is affecting weather patterns across the entire Southern Hemisphere, according to a new scientific study.

The findings published by researchers from Columbia University's School of Engineering and Applied Science is, they say, the first to demonstrate how ozone depletion in the polar region influences tropical circulation and increases rainfall at lower latitudes.

"It's really amazing that the ozone hole, located so high up in the atmosphere over Antarctica, can have an impact all the way to the tropics and affect rainfall there -- it's just like a domino effect," said lead author of the paper, Sarah Kang.

Using state-of-the-art climate models -- created by the Canadian Center for Climate Modeling and Analysis at the University of Victoria, British Columbia -- Kang and co-author Lorenzo Polvani (a research scientist at the LamontDoherty Earth Observatory) calculated atmospheric changes produced by creating an ozone hole and then compared these with observed changes over the last few decades.

The close correlation between the climate model and the observed changes led Kang and Polvani to conclude that the hole in the Antarctic ozone -- first discovered by scientists in the mid-1980s -- to be the likely cause of the atmospheric changes in the Southern Hemisphere. (read more)