Ocean acidification of the North Pacific Ocean

The addition of fossil fuel carbon dioxide to the atmosphere is rapidly changing seawater chemistry and the calcium carbonate saturation state of the world’s oceans as a result of the acidifying effects of CO2 on seawater. This acidification makes it more difficult for many marine organisms (e.g., corals, plankton, calcareous algae, and mollusks) to build skeletons, tests, and shells of calcium carbonate. Impacts on these calcifying organisms could lead to substantial changes in marine ecosystems. Repeat hydrographic and time-series data for the North Pacific show direct evidence for ocean acidification. These dramatic changes can be attributed, in most part, to anthropogenic CO2 uptake by the ocean over the past several decades.