What's Next - MACAN

What is acidification

Ocean Acidification (OA) is a pressing environmental concern that affects the health of our oceans and the people who use them.

Overview

Why It Matters

Carbon dioxide gas dissolves so readily in seawater that approximately one quarter of human caused CO₂ emissions become sequestered in the ocean. Once in the ocean, CO₂ combines with water to form a weak acid, resulting in a change in the chemistry of the sea.

The Chemistry of Ocean Acidification

The other major change in seawater chemistry involves CO₂-driven changes in the solubility of calcium carbonate minerals (CaCO₃) used by many marine plants and animals to build their shells and skeletons.rnrnThe solubility of CaCO₃ minerals depend on the amount of dissolved carbonate ions in seawater.rnrnMore CO₂ and lower pH reduces the concentration of carbonate ions, making it more difficult for many organisms to make shell material.

Ocean CO₂ and pH from NOAA: Correlation between rising levels of CO2 in the atmosphere at Mauna Loa with rising CO₂ levels in ocean at Station Aloha. As the CO₂ increases, the pH decreases; indicating increasing acidificication.

Coastal and Ocean Acidification Stressors Need for Information What’s Next

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What Lies Ahead

The Federal Ocean and Acidification Research Monitoring (FOARAM) Act, reauthorized by Congress in 2022, strengthens investments in acidification research, monitoring, and studies on socioeconomic impacts. Coastal Acidification Networks, like MACAN, NECAN, and SOCAN, provide an important bridge, connecting scientists, local government, and industry members to address acidification impacts at the regional level. At the local level, Mid-Atlantic states are taking a closer look at acidification’s implications in their waters. Learn more about state-led OA action planning initiatives here.

Acidification Will Continue to Influence All Areas of the Mid-Atlantic, From its Tidal Estuaries to Deep Sea Ecosystems

Acidification will continue to influence all areas of the Mid-Atlantic, from its tidal estuaries to deep sea ecosystems. The cooler, less salty waters of the upper Mid-Atlantic are particularly susceptible to ocean acidification, making reductions in the survival, calcification, growth, development, and abundance of marine organisms more likely. The organisms impacted most negatively and directly will likely be calcified algae, corals, mollusks, and echinoderms. Crustaceans, fleshy algae, seagrasses, and diatoms may be less directly affected or may even benefit from acidification. Even still, questions regarding food web impacts that may indirectly negatively impact all species remain.

Acidification May Hamper Efforts to Protect and Preserve the Mid-Atlantic’s Cultural Underwater Resources

The “Ghost Ship fleet” of Mallows Bay-Potomac River National Marine Sanctuary is one such resource. Anticipating damage to metal structures on the ships and other potential impacts, sanctuary managers are beginning to address climate change through their sanctuary management plans. As outlined in the report, Climate Change Impacts: Mallows Bay-Potomac River National Marine Sanctuary, strong partnerships between NOAA, the state of Maryland, and local organizations have been key to establishing a water monitoring network and supporting research on acidification and other climate stressors.

Photo: National Marine Sanctuary

Combating Acidification Won’t Be Easy, But Scientists, Governments, and NGOs Are Working to Identify Approaches to Help

Mitigation

Changing behavior and advancing technologies to decrease the carbon dioxide that causes acidification.

Remediation

Taking steps to lessen the acidity of water, such as planting eelgrasses that take up carbon dioxide.

Adaptation

Making changes in response to the symptoms of acidification, such as breeding shellfish that are more resistant to acidified waters.

Innovative Ideas for Mitigation, Remediation, and Adaptation of Acidified Waters Will Continue to Evolve

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References

EK Towle, AC Baker, C Langdon. 2016. Preconditioning to high CO₂ exacerbates the response of the Caribbean branching coral Poritesporites to high temperature stress. Marine Ecology Progress Series; 546: 75-84. DOI: 10.3354/meps11655. https://doi.org/10.3354/meps11655

E Ramirez-Llodra, PA Tyler, MC Baker, OA Bergstad, MR Clark, E Escobar, LA Levin, L Menot, AA Rowden, CR Smith, CL Van Dover. 2011. Man and the last great wilderness: human impact on the deep sea. PLoS ONE 6(8): e22588. https://doi.org/10.1371/journal.pone.0022588

RC Chambers, AC Candelmo, EA Habeck, ME Poach, D Wieczorek, KR Cooper, CE Greenfield, and BA Phelan. 2014. Effects of elevated CO₂ in the early life stages of summer flounder, Paralichthys dentatus, and potential consequences of ocean acidification. Biogeosciences 11.6: 1613-1626. https://doi.org/10.5194/bg-11-1613-2014

GG Waldbusser, EP Voigt, H Bergschneider, MA Green, RIE Newell. 2011. Biocalcification in the eastern oyster (Crassostrea virginica) in relation to long-term trends in Chesapeake Bay pH. Estuaries and Coasts 34.2: 221-231. https://doi.org/10.1007/s12237-010-9307-0

Ekstrom, J. A., Suatoni, L., Cooley, S. R., Pendleton, L. H., Waldbusser, G. G., Cinner, J. E., Ritter, J., Langdon, C., Van Hooidonk, R., Gledhill, D., Wellman, K., Beck, M. W., Brander, L. M., Rittschof, D., Doherty, C., Edwards, P. E. T., & Portela, R. (2015). Vulnerability and adaptation of US shellfisheries to ocean acidification. Nature Climate Change, 5(3), 207–214. https://doi.org/10.1038/nclimate2508

Speir, C., Ryan, G., & Mayo, C. (2016). Fisheries Economics of the United States, 2014 (NOAA Technical Memorandum, p. 246). NOAA. https://spo.nmfs.noaa.gov/sites/default/files/TM163.pdf

Wang, Z. A., Wanninkhof, R., Cai, W.-J., Byrne, R. H., Hu, X., PenSabag, T.-H., & Huang, W.-J. (2013). The marine inorganic carbon system along the Gulf of Mexico and Atlantic coasts of the United States: Insights from a transregional coastal carbon study. Limnology and Oceanography, 58(1), 325–342. https://doi.org/10.4319/lo.2013.58.1.0325