Underwater catastrophe

Ocean acidification, one of the world's most important climate-change challenges, must not be left off the agenda at the United Nations Copenhagen conference, the world's science academies said this week.

Ocean acidification is expected to cause massive corrosion of coral reefs and dramatic changes in the makeup of the biodiversity of oceans and to have significant implications for food production.

The warning was made in a joint statement published by the Royal Society (the UK national academy of science) and the academies of 69 other countries around the world.

Martin Rees, president of the Royal Society, said: 'Everybody knows that the increasing concentration of carbon dioxide in the atmosphere leads to climate change. 

'But it has another environmental effect - ocean acidification - which hasn't received much political attention.

'Unless global CO₂ emissions can be cut by at least 50 per cent by 2050 and more thereafter, we could confront an underwater catastrophe, with irreversible changes in the makeup of our marine biodiversity.

'Copenhagen must address this very real and serious threat.'

The statement calls for world leaders to explicitly recognise the direct threats posed by increasing atmospheric CO₂ emissions to the oceans and its profound impact on the environment and society. 

It emphasises that ocean acidification is irreversible and, on current emission trajectories, suggests that all coral reefs and polar ecosystems will be severely affected by 2050 or even earlier. 

The statement was issued during the UNFCCC conference in Bonn.

The conference will ultimately shape the Copenhagen negotiations, where agreement must be reached on carbon-emission reduction targets needed to avoid climate change.