Scientists have called for rapid curbing of carbon dioxide emission levels in order to limit ocean acidification as well as global warming.

Dr. Toby Tyrrell of the University of Southampton’s School of Ocean and Earth Science and colleagues used computer models to quantify the likely response of ocean acidification to a range of carbon dioxide emission scenarios, including aggressive mitigation.

“Our computer simulations allow us to predict what impact the timing and rapidity of emission reductions will have on future acidification, helping to inform policy makers,” said Tyrrell.

“The oceans absorb around a third of carbon dioxide emissions, which helps limit global warming, but uptake of carbon dioxide by the oceans also increases their acidity, with potentially harmful effects on calcifying organisms such as corals and the ecosystems that they support,” he added.

Changes in ocean pH over subsequent centuries will depend on how much the rate of carbon dioxide emissions can be reduced in the longer term.

Global mean ocean surface pH has already decreased from around 8.2 in 1750 to 8.1 today (decrease in pH corresponds to an increase in acidity).

“Over the longer term, out to say 2500, the minimum pH will depend on just how far the annual rate of carbon dioxide emissions can be reduced to,” said Tyrrell.