CLIMATE change is turning the oceans more acid in a trend that could endanger everything from clams to coral and be irreversible for thousands of years. Seventy academies from around the world urged governments meeting in Bonn for climate talks from June 1-12 to take more account of risks to the oceans in a new UN treaty for fighting global warming due to be agreed in Copenhagen in December.
The academies said rising amounts of carbon dioxide, the main greenhouse gas emitted mainly by human use of fossil fuels, were being absorbed by the oceans and making it harder for creatures to build protective body parts.
The shift disrupts ocean chemistry and attacks the "building blocks needed by many marine organisms, such as corals and shellfish, to produce their skeletons, shells and other hard structures", they said.
On some projections, levels of acidification in 80 per cent of Arctic seas would be corrosive to clams that are vital to the food web by 2060, it said.
And "coral reefs may be dissolving globally" if atmospheric levels of carbon dioxide were to rise to 550 parts per million (ppm) from a current 387 ppm.
Corals are home to many species of fish.
"These changes in ocean chemistry are irreversible for many thousands of years and the biological consequences could last much longer," they said.
Martin Rees, president of the Royal Society, the British science academy, said there may be an "underwater catastrophe".
"The effects will be seen worldwide, threatening food security, reducing coastal protection and damaging the local economies that may be least able to tolerate it," he said.
The academies said that if current rates of carbon emissions continue until 2050, computer models indicate "the oceans will be more acidic than they have been for tens of millions of years".
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