Otopljavanje u Sibiru- direktan uticaj globalnog zagrevanja

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Grenland,Arktik,Aljaska,Sibir..... bas se pitam sta li je sledece i jos neko da kaze da nema opasnosti od globalnog zagrevanja....



In Siberia an area of permafrost the size of Western Europe has started to melt. Scientists fear it may rapidly accelerate global warming. Plus, Pakistan tests a nuclear missile, while one Australian politician shows a bit of class by giving a colleague the finger.

An area of Siberian permafrost the size of France and Germany combined is thawing rapidly and could dramatically accelerate global warming, scientists have discovered. The world's largest peat bog -- a million square kilometres in size -- is starting to thaw. There are fears that this could release billions of tons of methane into the atmosphere.

A report outlining details of the findings in this week's New Scientist magazine makes for grim reading. Judith Marquand (Oxford University) and Sergei Kirpotin (Tomsk State University) made the discovery while undertaking research in western Siberia. The researchers discovered that an enormous area of frozen peat bog, first formed over 11,000 years ago, is rapidly beginning to thaw, releasing huge quantities of the potent greenhouse gas methane into the atmosphere.

Methane is naturally released by peat bogs but in western Siberia it has been locked into the permafrost. Until now, that is. The melt threatens to release 70 billion tons of the gas, one quarter of the world's total supply of landlocked methane.

Climate experts have reacted with concern to the findings, and are revising previous estimates of the impact of global warming. Dr Kirpotin told the New Scientist that what is happening in Siberia is an "ecological landslide that is probably irreversible and is undoubtedly connected to climatic warming."

Stephen Sitch, a climate expert at Britain's Meteorological Office, told the Guardian newspaper that the gradual thawing of Siberia's permafrost over the next 100 years would add approximately 700m tons of carbon to the world's atmosphere each year. This would lead to a doubling in atmospheric levels of the gas, and increase global warming by between 10 and 25 percent.

There are fears that western Siberia could be a ticking climatic time bomb. The area has warmed by over three degrees celsius in the past 40 years. Once the permafrost has disappeared, there is no putting it back. As the process occurs, exposed bare earth accelerates the rate at which the rest of the permafrost melts, because it warms far more quickly than ice or snow.

The last intergovernmental study on climate change predicted a rise of between 1.4 and 5.8 degrees Celsius in global temperatures by 2100. This estimate only took account of known greenhouse gas emissions and will now therefore require revision.

Regina Günther, head of the Climate & Energy department at the World Wide Fund (WWF) told SPIEGEL Online that some degree of climate change is inevitable, but action must be taken to prevent its most devastating effects. "Scientists tell us that it's hardly possible to avoid a two degree rise in average global temperatures but we should take action to ensure we do not exceed this limit. We are carrying out a very dangerous experiment with our planet."

A new report by WWF has shown how European cities have been getting progressively hotter over the past 30 years. Average summer temperatures were at least one degree higher in all major European cities over the past five years, than 30 years ago. London's average summer temperature is now two degrees higher than it was in the 1970s.

Last month's G8 meeting failed to deliver an agreement on greenhouse emission targets. Australia and the US recently announced a package of measures to tackle climate change, based around the use of new technologies. All parties have been widely criticised for not doing enough.

http://service.spiegel.de/cache/international/0,1518,369276,00.html