Raging Waters In Australia and Brazil Product of Global Warming

Jan. 13, 2011— -- The pictures today from around the world of dramatic rooftop rescues from raging waters, makes it seem as though natural disasters are becoming an everyday occurrence. But they're not all that natural; climate scientists say man-made global warming is the sudden force behind the forces of nature.

In the mountains of southeast Brazil, more than 340 people have died after fierce mudslides swept away homes. At least 50 are still missing and victims continue to search for loved ones. On the other side of the globe, floods in Queensland, Australia have ravaged an area the size of France and Germany combined.

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"Things are pretty devastating," June Lense, a resident of Brisbane, said.

And in Sri Lanka, officials say flooding there has affected more than a million people, and the death toll has risen to 23. Sewage lines and holding tanks have overflowed in the floods, and a spokesperson for the health ministry there said officials are concerned about waterborne diseases like typhoid and diarrhea.

"If left unchecked, climate warming will continue so the things that we're having hints of now, foretastes of now, will come stronger," Richard Sommerville, a climate scientist at the University of California at San Diego and author of "The Forgiving Air: Understanding Environmental Change," said.

The extreme weather the world has seen is part of a larger trend, he said. "The world is warming up ... It's warming for sure and science is very confident that most of the warming is due to human causes."

Every time we burn fossil fuels like coal, oil and natural gas, Sommerville said, we emit carbon dioxide into the atmosphere. Now, climate scientists see "the changed odds, the loaded dice that favors more extreme events and more high temperature records being broken," he said.

The decade that just ended saw nine of the 10 warmest years on record, and warmer temperatures mean more moisture in the air. That moisture can fall as torrential, flooding rains in the summertime or blizzards in the winter.

"Because the whole water cycle speeds up in a warming world, there's more water in the atmosphere today than there was a few years ago on average, and you're seeing a lot of that in the heavy rains and floods for example in Australia," Sommervile said.