Ocean Acidification Threatens Southern Oceans

In response to watching one too many kitchy Batman episodes one of my childhood fears including being dropped in a vat of acid – – sounds ridiculous now, but such is the future for corals and marine animals with calcium carbonate shells.


Although the chemistry of ocean acidification due to increased carbon dioxide has only recently been recognized, the impacts to marine life are already visible. Will Howard and Andrew Moy from the Antarctic Climate and Ecosystems Cooperative Research Centre in Hobart, Tasmania looked at shells in a group of plankton called Foraminifera. They compared average shell weight in organisms that are alive today with those of fossils as old as 20,000 years. Since industrialization, the average shell weight of one species of Foraminifera has declined 38 percent.

Increased acidity makes it harder for organisms like plankton, coral and clams to make shells and other structures from calcium. The question is how will this affect marine ecosystems? Plankton are the foundation of marine food chains, and any changes to them will have ripple effects throughout the ecosystem, ultimately affecting species that humans rely on directly. Howard and Moy say their findings highlight the need for nations to work together to reduce carbon dioxide emissions quickly.

SOURCES: Hobart Mercury, Sydney Morning Herald