The pH levels of the world's oceans are starting to drop dramatically, affecting everything from molluscs to fish, to the amount of carbon the seas are absorbing.
This phenomenon is known as "ocean acidification" - and it's a big deal, being dubbed the "evil twin of global warming".
We cross to Dunedin, site of an ongoing international conference on acidification, to chat to Dr Kim Currie from NIWA about this phenomenon, what its implications are, and how we can stop it.
Photo: s
