Ocean acidification threatening marine species

New Zealand scientists say climate change is slowly beginning to threaten sea life, in a new review on how marine species will fare in a warmer world. Measured by a reduction in sea water pH, ocean acidification is mostly driven by oceans absorbing and storing the increasing load of carbon dioxide that humans are pumping into the atmosphere. Kathryn Ryan speaks with one of the report's authors, associate professor of marine science Dr Chris Hepburn.