Seas Becoming More Acidic, Scientists Warn

Ten times faster than has ever been recorded

Rapidly rising carbon dioxide levels in the atmosphere are causing a potential catastrophe in our oceans as they become more acidic, scientists have warned.

Hans Poertner, professor of marine biology at the Alfred Wegener Institute in Germany, and co-author of a new study of the phenomenon, told the Guardian: "The current rate of change is likely to be more than 10 times faster than it has been in any of the evolutionary crises in the earth's history."

Seawater is naturally slightly alkaline, but as oceans absorb CO2 from the air, their pH level falls gradually. Under the rapid escalation of greenhouse gas emissions, ocean acidification is gathering pace and many forms of marine life – especially species that build calcium-based shells – are under threat.