Ocean acidification appears to have potential to be a significant problem. Past declines in ocean surface pH have been linked to mass extinction events (Guinotte and Fabry, 2008). While I am not an expert in the science, the issue starts with declines in pH (increased acidity) causing a reduction in carbonate ion concentration which in turn causes a reduction in calcium carbonate saturation. This has impacts on marine organisms that are calcifiers and essentially requires marine calcifying organisms to use more energy to form biogenic calcium carbonate (Guinotte and Fabry, 2008). The observable consequences are thought to be hampered reef formation of corals, algaes and hampered shell formation of oysters, clams and crabs (although there are varying consequences on species depending on studies as shown by Dr. Cooley).
Finnoff D., Modeling economic impacts of climate change and ocean acidification to fisheries. EPA report. pp 11. Article.
