Greenpeace

The world's scientific academies - including the UK's Royal Society - issued a warning that ocean acidification must be on the agenda when countries attempt to forge a new global deal on cutting emissions in Copenhagen in December.

And a separate paper warned that increasing acidity in the seas could damage fish, corals and shellfish - leaving fishing communities facing economic disaster.

The researchers from Woods Hole Oceanographic Institution, Massachusetts, said emissions from deforestation and burning of fossil fuels had increased levels of CO2 in the atmosphere by almost 40 per cent above pre-industrial levels.

Currently around 30 per cent of the CO2 put into the atmosphere by human activities is absorbed by the oceans where it dissolves, altering the chemistry of the surface sea levels making it more acidic.The acidity can damage wildlife, particularly shell-forming creatures and the species which feed on them, with knock-on effects on people who rely on the oceans for food and livelihoods.