THE WORLD's oceans could 'flip' to a different pattern of circulation in as little as 50 years, releasing huge stores of heat into the atmosphere, Peter Killworth of the Hooke Institute of Atmospheric Research in Oxford told the conference. In a separate talk, Philip Williamson of the Plymouth Marine Laboratory said that practical problems could undermine an American proposal to slow global warming by speeding up the growth of plankton that absorb carbon dioxide, the main greenhouse gas.
Killworth said the top few metres of the oceans store more heat than the whole of the atmosphere. They were expected to absorb heat arising from global warming, but if the warming causes ocean circulation to change, heat could be released instead.
A change in ocean circulation would release about 100 watts per square metre to the atmosphere, four times more than the warming expected from the greenhouse effect.
Although it could ...
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