Australia has a direct stake in the ocean acidification problem: it will affect every part of our marine environment. And our offshore estate has just become a lot bigger. Three months ago the UN Commission on the Limits of the Continental Shelf, while not accepting all bids, recognised Australia's claim to the continental shelf where it extends beyond our exclusive 200 nautical mile economic zone. This is a vast oceanic area: 2.5 million square kilometres, or 10 times the size of New Zealand and 20 times the size of Britain.

Rising levels of acidity in the oceans surrounding Australia could have a profound impact on marine industries and dire consequences for many Pacific Island communities, presenting strategic and humanitarian challenges.

Mounting levels of CO2 in the Southern Ocean has caused deep concern among scientists studying the long-term productivity of the world's oceans. Under conditions of increasing acidification, parts of the oceans will deteriorate and progressively become uninhabitable for certain types of plankton, central to the ocean food chain, and coral structures. The Southern Ocean is particularly important because it is very efficient at absorbing CO2 from the atmosphere: it's here where the first effects are being felt.

Ocean acidification is likely to have a cascading effect, reaching parts of the food chain such as fish and shellfish. Marine researchers are saying that a business-as-usual scenario of CO2 production will ultimately result in destruction of marine life on an enormous scale.

Some shell-forming species will struggle to maintain or reproduce their vital shell structures and skeletons, which will have a direct effect on the ocean food web.

Some species will decline, others will be displaced or will disappear, and patterns of fisheries will change, potentially threatening the food security of millions in the Asia-Pacific and damaging Australian fisheries economically.