Expect a climatic wild ride

The world -- especially the Western United States, the Mediterranean region and Brazil -- will likely suffer more extended droughts, heavy rainfalls and longer heat waves over the next century because of global warming, a new study forecasts.

But the prediction of a future of nasty extreme weather also includes fewer freezes and a longer growing season.

In a preview of a major international report on climate change that comes out next year, a study out of the National Center for Atmospheric Research details what nine of the world's top computer models predict for the lurching of climate at its most extreme.

"It's going to be a wild ride, especially for specific regions," said study lead author Claudia Tebaldi, a scientist at the federally funded academic research center.

Tebaldi pointed to the Western U.S., Mediterranean nations and Brazil as "hot spots" that will get extremes at their worst, according to the computer models.

And some places, such as the Pacific Northwest, are predicted to get a strange double whammy of longer dry spells punctuated by heavier rainfall.

As the world warms, there will be more rain likely in the tropical Pacific Ocean, and that will change the air flow for certain areas, much like El Nino weather oscillations now do, said study co-author Gerald Meehl, a top computer modeler at the research center. Those changes will affect the U.S. West, Australia and Brazil, even though it's on South America's eastern coast.

For the Mediterranean, the issue has more to do with rainfall in the tropical Atlantic Ocean changing air currents, he said.