Raging Waters In Australia and Brazil Product of Global Warming

The raging waters in Australia and Brazil attributed to man-made global warming.

January 13, 2011, 3:11 PM

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.

Scientists Say They're Observing Climate Change

Last year tied with the warmest on record, according to the National Oceanic and Atmospheric Administration. Derek Arndt, chief of NOAA's Climate Monitoring Branch in the National Climate Data Center, said 2010 was "an exclamation point on several decades of warming."

He said NOAA is tracking disasters like the floods in Brazil and Australia. "We are measuring certain types of extreme events that we would expect to see more often in a warming world, and these are indeed increasing," Arndt said.

The added moisture in the atmosphere also explains the phenomenon we've seen this week at home -- where snow blanketed the ground in 49 of 50 states. During yesterday's snowstorm, Hartford, Conn. and Albany, N.Y. both set records for snowfall in a single day.

"This is no longer something that's theory or conjecture or something that comes out of computer models," Sommerville said. "We're observing the climate changing -- it's happening, it's real, it's a fact."

ABC News' Julia Bain and The Associated Press contributed to this report.

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