Mea culpa- I did not remember the document I read correctly. The carbonic acid references are usually a separate but related concern. As CO2 dissolves in water, it changes the pH balance, which is having a detrimental effect on sea life (esp. on the micro scale) in the area. This is more prevalent at the poles, due to CO2 more readily dissolving into cold water.

http://www.catlinarcticsurvey.com/Science.aspx