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Ocean Acidification Data for Coasts

NOAA spearheads North American collaboration

Photo of Caribe coast and horizon
Courtesy of NOAA

Vulnerable coastal areas now have a tool to assess the status and impacts of ocean acidification (OA). NOAA and collaborators have compiled data about OA conditions for the entire continental shelves of North America, from Alaska to Mexico in the west and from Canada to the Caribbean in the east.

Ocean acidification results from the ocean’s absorption of carbon dioxide (CO2) from the atmosphere and increases the acidity of seawater. Although this process helps reduce levels of CO2 in the atmosphere and thus slows down global climate change, it comes at a cost to aquatic ecosystems and local fisheries. Acidified water can harm fish, oysters, clams, sea urchins, shallow water corals, and deep-sea corals, among other living organisms. 

The Coastal Ocean Data Analysis Product for North America (CODAP-NA) fills a gap for information about the water column that can indicate acidification. Prior to now, no such data products existed for the coastal ocean where most of the OA-susceptible commercial and recreational fisheries and aquaculture industries are located. Previous OA products have mostly been focused on the open ocean, although the majority of the fisheries yield is located in the coastal ocean.

NOAA researches potential impacts of OA on marine resources through the Ocean Acidification Program, which funded this new product’s development. Coastal regions support about 90% of the global fisheries yield and 80% of known species of marine fish. Changes in the ocean can change the way humans make their living, run their communities, and live their lives in coastal regions around the world.

Collaboration to Track Acidification

To create CODAP-NA, researchers from across NOAA—including NCEI, Pacific Marine Environmental Laboratory, Atlantic Oceanographic and Meteorological Laboratory, and Northeast Fisheries Science Center—collaborated with colleagues from ten academic institutions that have stakes in vulnerable regions. Partnering institutions included the University of Maryland at College Park, University of Miami, University of Washington, University of New Hampshire, University of Delaware, University of Alaska Fairbanks, Georgetown University, University of South Florida, Oregon State University, and The University of Maine. A total of twenty-five individual investigators participated in the effort. 

The team compiled, quality controlled, and synthesized two decades of discrete measurements. The inaugural version of CODAP-NA is composed of 3,292 oceanographic profiles from 61 research cruises and relies on data only from laboratories with quality assurance practices. The data product contains 14 oceanographic parameters from the water column, including temperature, salinity, oxygen, nutrients, pH, calcium carbonate mineral saturation states, dissolved inorganic carbon, and total alkalinity. 

OA Data for the Future

CODAP-NA greatly improves the data’s findability, accessibility, interoperability, and reusability—the FAIR principles of data management. "This product will help coastal enterprises and decision-makers develop strategies to adapt to the severity of ocean acidification and promote more OA research within the U.S. Exclusive Economic Zone," says Dr. Richard A. Feely, a NOAA oceanographer and co-author of the study. CODAP-NA provides a foothold for future efforts by creating an internally consistent OA data product for the coastal environment, and quality control of coastal OA data will be ongoing. 

The dataset is publicly available from NCEI in Excel, CSV, MATLAB, and NetCDF. 

Reference: Jiang, L.-Q., Feely, R. A., Wanninkhof, R., Greeley, D., Barbero, L., Alin, S., Carter, B. R., Pierrot, D., Featherstone, C., Hooper, J., Melrose, C., Monacci, N., Sharp, J. D., Shellito, S., Xu, Y.-Y., Kozyr, A., Byrne, R. H., Cai, W.-J., Cross, J., Johnson, G. C., Hales, B., Langdon, C., Mathis, J., Salisbury, J., and Townsend, D. W.: Coastal Ocean Data Analysis Product in North America (CODAP-NA) – an internally consistent data product for discrete inorganic carbon, oxygen, and nutrients on the North American ocean margins, Earth Syst. Sci. Data, 13, 2777–2799,, 2021.