"The UK's Royal Society has launched an investigation into the rising acidity of the world's oceans due to pollution from the greenhouse gas carbon dioxide. The change could have catastrophic consequences for marine life.
Oceans mop up carbon dioxide from the atmosphere, lowering the water's pH value - an effect that may be exacerbated by burning of fossil fuels. Scientists on the working group are due to publish an initial report into the phenomenon by early next year.
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The Intergovernmental Oceanographic Commission reports that some 20-25 million tonnes of carbon dioxide are being added to the oceans each day. Researchers believe such dramatic changes in the carbon dioxide system in surface waters have not been observed for more than 20 million years of Earth history.
Delicate balance
Experts currently predict that if this trend continues, ocean pH could fall by as much as 0.4 units by the year 2100. "The thing about acidification is that it is happening at the same time that the oceans are warming, so organisms are going to have to deal with two major changes," working group member Dr Carol Turley of Plymouth Marine Laboratory told BBC News Online."
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http://news.bbc.co.uk/1/hi/sci/tech/3571152.stm