Lets just hope that it is not this.

Permafrost melt could speed up global warming 500 billion tons of extra 
CO{-2} could be released, study says.

Global warming might be significantly worse than expected during the next 
century because the melting of carbon-rich permafrost in Siberia could 
expel hundreds of billions of tons of extra greenhouse gases into the 
atmosphere, scientists warn in a new study. 

Experts said they can't be certain how large the impact might be, because 
they can't accurately estimate how much of the extra greenhouse gases will 
be absorbed by plants and the oceans. 

One of the more frightening possibilities is that the permafrost-caused 
warming could feed on itself in what one scientist called a "vicious 
cycle": That is, it could trigger the melting of additional ice, which 
would unleash more greenhouse gases and thus cause more warming, in a self-
repeating cycle for no one knows how long. 

The melting of Siberian permafrost that has been frozen for thousands of 
years could eject about 500 billion tons of carbon dioxide into the 
atmosphere during the next century, scientists from Russia, Alaska and 
Florida report in today's issue of Science. By comparison, at present the 
atmosphere contains about 700 billion tons of greenhouse gases. 

"I'm a scientist, so we tend to be conservative in our language. But I 
would say this could make global warming significantly worse" than 
expected, said E.A.G. "Ted" Schurr, a former UC Berkeley doctoral student 
who is one of the article's three authors. The other authors are Sergey A. 
Zimov of the Russian Academy of Sciences and Terry Chapin of the University 
of Alaska at Fairbanks. 

Schurr, now a professor of botany at the University of Florida in 
Gainesville, traveled to Siberia to collect samples of permafrost -- 
permanently frozen ground rich in carbon-laden dust particles that have 
accumulated over a million and a half years. He extracted permafrost 
samples from up to 10 feet beneath the ground, then hauled them back to 
Florida in standard coolers, stopping from time to time to refreeze the 
samples in a fridge so they wouldn't melt en route. 

When he allowed the permafrost to melt in his lab in Gainesville, microbes 
attacked and absorbed the carbon, transforming much of it into carbon 
dioxide gas. Schurr measured the rate of carbon dioxide emission by shining 
an infrared beam through it. The estimate of 500 billion tons in extra 
greenhouse emissions was derived partly from this analysis. 

Carbon dioxide is the best-known greenhouse gas: It accelerates global 
warming by trapping infrared radiation before it can leave the atmosphere. 
Fossil fuels, when burned by cars and factories, are major sources of 
atmospheric carbon dioxide. 

Leading climate models haven't incorporated the possibility of a major new 
greenhouse gas source from Siberia. The new report "makes it kind of scary -
- it means there's a form of climate risk that we really haven't got a good 
handle on," said Chris Field, director of the Carnegie Institution's 
Department of Global Ecology at Stanford. 

He was not directly connected with the study published in Science, but he 
and colleagues are working with the authors to incorporate their findings 
in improved computer models of future climate change. 

In interviews Thursday, experts who aren't connected with the Science paper 
had varied reactions. 

"It could raise temperatures dramatically beyond the current projections. 
Second, it could raise the rate at which temperatures rise," 
paleoclimatologist David Anderson of the National Oceanic and Atmospheric 
Administration's National Climate Prediction Center in Boulder, Colo., said 
in a phone interview. 

Anderson noted that present-day models estimate the average planetary 
temperature will rise by 5.5 degrees Fahrenheit if carbon dioxide levels 
double. It's uncertain, though, how fast that doubling (which is driven in 
part by fast-spreading industrialization and car ownership) could occur. 

"Conceivably, (permafrost melting) could eventually -- say within several 
centuries -- have as much impact as the burning of fossil fuels," raising 
the average planetary temperature by more than 10 degrees, Anderson said. 

The Science study shows the amount of carbon frozen in permafrost around 
the world, not just Siberia, is much higher than previously calculated, a 
climate expert at Lawrence Livermore National Laboratory said. 

"We have known (about) the permafrost in Siberia before," explained 
atmospheric scientist Bala Govindasamy of the lab. "Previous estimates for 
global permafrost (are) between 200 and 400 (billion tons). This study has 
found higher carbon content in the Siberian permafrost and estimates that 
the total global amount could be about 1,000 (billion tons)." 

The U.N.-sponsored Intergovernmental Panel on Climate Change produced an 
original estimate for global warming of 3 to 11 degrees Fahrenheit over the 
next century, Govindasamy said. He added that the new permafrost data might 
push the estimate much higher -- to 5 to 15 degrees. 

Kevin Trenberth, one of the nation's top climate modelers, said it's "hard 
to say" how much the findings could affect forecasts of global warming, but 
the effects are "likely nontrivial," he said in an e-mail. 

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