Ocean Acidification


Ocean Acidification

Ocean acidification is the reduction in the pH of the ocean over an extended period, caused primarily by uptake of carbon dioxide (CO2) from the atmosphere. Since the beginning of the industrial revolution (200+ years ago), the concentration of carbon dioxide in the atmosphere has increased due to human activities, such as burning fossil fuels and deforestation, and surface ocean waters has become 30 percent more acidic (i.e., pH has fallen). Because the ocean absorbs about 30% of the carbon dioxide in the atmosphere, increasing levels of anthropogenic carbon dioxide in the atmosphere results in increased carbon dioxide in the ocean. When carbon dioxide is absorbed by seawater, chemical reactions occur that reduce seawater’s pH and its carbonate ion concentration. 

Many marine organisms (e.g., oysters and other bivalves, sea urchins, corals, and calcareous plankton) use carbonate to build shells and skeletal structures. Therefore, decreases in seawater carbonate ions can make it difficult for these organisms to build and maintain shells and skeletal structures, resulting in biological and physiological impacts that can affect organisms’ survival and growth, as well as ecosystems. 

The global impacts of ocean acidification on marine life lead to economic impacts on commercial fisheries and tourism to cultural impacts on indigenous people. For example, the U.S. Pacific Northwest is seeing the direct effects of ocean acidification, especially on its shellfish industry.

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Webinar Series

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    2022 Professional Development Webinars: Dr. Sean Hayes

    January 20, 2022|

    As climate change begins to have influences on the physical processes of the ocean there will be a variety of responses by most marine taxa. NOAA Fisheries is responsible for managing many if not most of these species in US waters. The presentation will highlight some general principles that can be expected, and then dive a little deeper into some case studies from several of NOAA’ Species in the Spotlight including seals, salmon, whales and more.

    2022 Professional Development Webinars: Dr. Andrea Copping & Dorian Overhus

    January 6, 2022|

    As we combat climate change, marine renewable energy (MRE) has the potential to play an important role. However, we need to understand the impact tidal, wave, and ocean thermal energy devices may have on marine animals and the environment in order to deploy MRE devices in a responsible manner. This webinar will cover the importance of MRE and how it relates to climate change, what is known about environmental interactions, and next steps for the industry.

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