Global warming 'helps coral reefs grow'

Published on 09/12/2004 02:24

CORAL reefs could be growing 35 per cent faster by the next century because of global warming, it was claimed yesterday.

A new study suggests the effects of warmer waters might offset damage caused by greenhouse gases as higher amounts of dissolved carbon dioxide reduce the levels of calcium and carbonate in seawater needed to make corals.

A team from the University of New South Wales, in Sydney, modelled interactions between the atmosphere, oceans and ice. They calculated the sea’s surface temperature and the levels of calcium carbonate in the water up to 2100 before estimating how these changes would affect the formation of corals.

They found that warmer water would increase the rate of coral calcification, outweighing the detrimental effect of lower calcium carbonate levels. By 2100, corals would be growing 35 per cent faster than they do today, they predicted.

But the finding, reported in New Scientist magazine, is rejected by other scientists, who argue that the Australian team did not consider bleaching, which occurs when warmer waters cause corals to expel the algae that live within them and on which they depend for survival.