Ocean Acidification. Harold F. Upton, Analyst in Natural Resources Policy; Peter Folger, Specialist in Energy and Natural Resources Policy. July 30, 2013

“With increasing concentrations of carbon dioxide (CO2) in the atmosphere, the extent of effectson the ocean and marine resources is an increasing concern. One aspect of this issue is the ongoing process (known as ocean acidification) whereby seawater becomes less alkaline as more CO2 dissolves in it, causing hydrogen ion concentration in seawater to increase. Scientists are concerned that increasing hydrogen ion concentration could reduce growth or even cause death of shell-forming animals (e.g., corals, mollusks, and certain planktonic organisms) as well as disrupt marine food webs and the reproductive physiology of certain species. While not yet fully understood, the ecological and economic consequences of ocean acidification could be substantial. Scientists are concerned that increasing hydrogen ion concentration in seawater could alter biogeochemical cycles, disrupt physiological processes of marine organisms, and damage marine ecosystems. This report does not discuss the effects of increasing thermal stress to marine organisms and ecosystems (e.g., coral bleaching) related to climate change. However, marine ecosystems are likely to be affected by the synergistic effects of factors involved in both thermal and chemical processes.”