Global CO2 Release From Peat Bogs Speeding Up - Positive Feedback Underway

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"The world’s peat bogs are haemorrhaging carbon dioxide into the atmosphere, accelerating global warming, warns a UK researcher. And worse still, the process appears to be feeding off itself, as rising atmospheric levels of carbon dioxide are triggering further releases from the bogs.

Billions of tonnes of carbon could pour into the air from peat bogs in the coming decades, says Chris Freeman of the University of Wales at Bangor, UK. “The world’s peatland stores of carbon are emptying at an alarming rate,” he says. “It’s a vicious circle. The problem gets worse and worse, faster and faster.”

Peat bogs are a vast natural reservoir of organic carbon. By one estimate, the bogs of Europe, Siberia and North America hold the equivalent of 70 years of global industrial emissions. But concern is growing that such bogs are releasing ever more of their carbon into rivers in the form of dissolved organic carbon (DOC). “There seems to be an increase of DOC in rivers of about 6 per cent a year at present,” says Fred Worrall of the University of Durham in the UK, who collates global data on DOC levels in rivers. Worrall suspects the rise in DOC began about 40 years ago.

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Recent data from the Centre for Ecology and Hydrology in Lancaster, UK shows a 90 per cent increase in DOC levels in Welsh mountain rivers since 1988. “The rate of acceleration suggests that we have disturbed something critical that controls the stability of the carbon cycle in our planet,” Freeman says. “On these trends, by the middle of the century, DOC emissions from peat bogs and rivers could be as big a source of CO2 to the atmosphere as burning fossil fuels.”

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http://www.newscientist.com/news/news.jsp?id=ns99996124

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1. Followup article from the Independent

"Global warming is set to dramatically worsen because of huge amounts of carbon dioxide (CO2) being released from the world's peatlands, a study has found.

Scientists analysing the huge stores of natural CO2 locked up in peatlands have found they are being released into the environment at an accelerating rate. At the current rate, the CO2 released from peatlands will exceed those produced by the burning of fossil fuel as early as 2060. If no action is taken and the peatland emission of greenhouse gases continues, the scientists estimate there will be no peatlands left by the end of the century and that levels of CO2 in the atmosphere would have doubled as a result.

The scientists also believe man-made pollution is behind the sudden and unexpected release of CO2 from the world's major peatbogs, which extend from North America to Siberia.

In a series of seminal experiments published today in the journal Nature, the researchers found that the increase in atmospheric CO2 seen in recent decades can have a direct impact on destabilising the carbon locked up in peat bogs."

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http://news.independent.co.uk/world/science_technology/story.jsp?story=539131