Friday, May 28, 2010

Global warming influence on El Nino still unknown

Terra Daily: The climate of the Pacific region will undergo significant changes as atmospheric temperatures rise but scientists can not yet identify the influence it will have on the El Nino-Southern Oscillation (ENSO) weather phenomenon. This is a central finding of an international science review by the World Climate Research Program's Climate Variability and Predictability Pacific Panel, published in Nature Geoscience.

The Panel convened in Australia at the Greenhouse 2009 climate change conference to consider new research that could build an understanding of changes in the behaviour of ENSO. ENSO is a naturally occurring phenomenon causing climate variability that originates in the tropical Pacific region and influences ecosystems, agriculture, freshwater supplies, hurricanes and other severe weather events worldwide.

"There is an increasing body of evidence pointing to significant changes in Pacific Ocean climate as a consequence of global warming," says co-author, Dr Wenju Cai from CSIRO's Wealth from Oceans Flagship. "What we are attempting to clarify is how those changes will enhance or moderate ENSO and, in Australia's case, deliver stronger or weaker El Nino events which would have vastly different implications," he says.

…Dr Power says ENSO will continue to have a profound influence on climate around the world over the coming century " This report shows, however, that determining how ENSO will change in response to further global warming and what this means for Australia and our Pacific neighbours is a real challenge."….

This image of the Pacific Ocean shows sea surface height relative to normal ocean conditions on Dec. 1, 1997. In this image, the white and red areas indicate unusual patterns of heat storage; in the white areas, the sea surface is between 14 and 32 centimeters (6 to 13 inches) above normal; in the red areas, it's about 10 centimeters (4 inches) above normal. The green areas indicate normal conditions, while purple (the western Pacific) means at least 18 centimeters (7 inches) below normal sea level.

1 comment:

Erl said...

The interest should be the other way round. How much of global warming, and cooling, or whatever is the theme of the moment, is due to ENSO. When science can explain the origins of ENSO we will get a handle on that issue.

The warming and cooling that we can observe and measure on a year to year and decadal basis is manifestly due to the forces that change sea surface temperature in the tropical oceans.