Fewer (autumn and winter) rain storms across southern Australia

[OKIsItJustMe]

http://www.csiro.au/news/Fewer-rain-storms-across-southern-Australia.html

Media Release

Fewer rain storms across southern Australia

Reference: 11/67

Decreasing autumn and winter rainfall over southern Australia has been attributed to a 50-year decrease in the average intensity of storms in the region – a trend which is forecast to continue for another 50 years.

4 July 2011

In an address today to the International Union of Geodesy and Geophysics conference in Melbourne, CSIRO climate scientist, Dr Jorgen Frederiksen, said these changes are due to reductions in the strength of the mid-latitude jet stream and changes in atmospheric temperatures. The jet stream comprises fast moving westerly winds in the upper atmosphere.

"The drop in winter and autumn rainfall observed across southern Australia is due to a large downturn in the intensity of storm formations over at least the last three decades compared with the previous three decades, and these effects have become more pronounced with time," Dr Frederiksen said.

"Our recent work on climate model projections suggests a continuation of these trends over the next 50 years."

Dr Frederiksen's address was based on recent CSIRO and Bureau of Meteorology research that has just been published in the International Journal of Climate Change: Impacts and Responses.

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