Biological Response

NOAA's Ocean Acidification Program supports research that focuses on economically and ecologically important marine species. Research of survival, growth, and physiology of marine organisms can be used to explore how aquaculture, wild fisheries, and food webs may change as ocean chemistry changes.


A number of NOAA National Marine Fisheries Service Science Centers have state-of-the-art experimental facilities to study the response of marine organisms to the chemistry conditions expected with ocean acidification.

The Northeast Fisheries Science Center has facilities at its Sandy Hook, NJ and Milford, CT laboratories; the Alaska Fisheries Science Centers at its Newport, OR and Kodiak, AK laboratories; and the Northwest Fisheries Science Center at its Mukilteo and Manchester, WA laboratories. All facilities can tightly control carbon dioxide and temperature. The Northwest Fisheries Science Center can also control oxygen, and can create variable treatment conditions for carbon dioxide, temperature, and oxygen. These facilities include equipment for seawater carbon chemistry analysis, and all use standard operating procedures for analyzing carbonate chemistry to identify the treatment conditions used in experiments.



Both deep sea and shallow reef-building corals have calcium carbonate skeletons.  As our oceans become more acidic, carbonate ions, which are an important part of calcium carbonate structures, such as these coral skeletons, become relatively less abundant. Decreases in seawater carbonate ion concentration can make building and maintaining calcium carbonate structures difficult for calcifying marine organisms such as coral.



Increased levels of carbon dioxide in our ocean can have a wide variety of impacts on fish, including altering behavior, otolith (a fish's ear bone) formation, and young fish's growth. Find out more about what scientists are learning about ocean acidification impacts on fish like rockfish, scup, summer flounder, and walleye pollock.


Shellfish, such as oyster, clams, crabs and scallop, provide food for marine life and for people, too. Shellfish make their shells or carapaces from calcium carbonate, which contains carbonate ion as a building block. The decreases in seawater carbonate ion concentration expected with ocean acidification can make building and maintaining calcium carbonate structures difficult for calcifying marine organisms like shellfish. This may impact their survival, growth, and physiology, and, thus, the food webs and economies that depend on them.


Plankton are tiny plants and animals that many marine organisms, ranging from salmon to whales, rely on for nutrition. Some plankton have calcium carbonate structures, which are built from carbonate ions. Carbonate ions become relatively less abundant as the oceans become more acidic. Decreases in seawater carbonate ions can make building and maintaining shells and other calcium carbonate structures difficult for calcifying marine organisms such as plankton. Changes to the survival, growth, and physiology of plankton can have impacts throughout the food web.


Integrated Modeling of Ocean Acidification and Hypoxia to Support Ecosystem Prediction and Environmental Management in the California Current System

James McWilliams, UCLA/IGPP

The California Current System (CCS) is one of the most biologically productive regions of the world ocean, but seasonal upwelling of low oxygen and low-pH waters makes it particularly vulnerable to even small additional reductions in O2 and/or pH, which have both been observed in recent decades. Three prominent coastal phenomena have been implicated in precisely these changes: 1) large scale acidification and deoxygenation of the ocean associated with climate warming, 2) natural climate variability, and 3) anthropogenic pollution of coastal waters, especially from nutrient discharge and deposition.  The relative importance of these drivers has not been systematically evaluated, and yet is critical information in any cost-effective strategy to manage coastal resources at local scales.  Disentangling the magnitude and interaction of these different ecosystem stresses requites an integrated systems modeling approach that is carefully validated against available datasets.

The goals of this project are three-fold: 1) develop an ocean hypoxia and acidifcation (OHA) model of the CCS (Baja California to British Columbia), comprising the circulation, biogeochemical cycles, and lower-trophic ecosystem of the CCS, with regional downscaling in the Southern California Bight, Central Coast, and the Oregon Coast; 2) use the model to understand the relative contributions of natural climate variability, anthropogenically induced climate change, and anthropogenic inputs on the status and trends of OHA in the CCS; and 3) transmit these findings to coastal zone mangers and help them explore the implications for marine resource management and pollution control.

Wednesday, January 25, 2017
Categories: Projects

Developing innovative tools to connect stakeholders with NOAA's Ocean Acidification Observing Network (NOA-ON)

Adrienne Sutton and Simone Alin, NOAA Pacific Marine Environmental Laboratory

Students from University of Washington's (UW) College of Computer Science & Engineering (CSE), are looking for local opportunities to apply their newly-acquired skills and gain experience in preparation for a competitive job market. We propose to leverage this local (and economical) tech resource by hiring student interns interested in working with the PMEL Carbon Program's large data collections and developing novel interactive tools for data visualization and communication that would serve the broader community of scientists, resource managers, and other stakeholders. We also propose to develop new 2D and/or 3D visualizations of observational data, model results, model-data comparisons, and conceptual diagrams related to OAP-funded work in the California Current Large Marine Ecosystem to improve the coastal OA community's ability to communicate with stakeholders about observed and forecasted conditions and potential impacts. This work will build on an existing partnership with UW's Center for Environmental Visualization (CEV), which built the PMEL Carbon Program website in 2010 and recently updated our antiquated Google Earth data portal ( The proposed work will contribute to improving the public's access to and ability to interact with data generated by the NOAA Ocean Acidification Observing Network (NOA-ON) with the goal of increasing awareness and understanding of ocean acidification (OA). 

Wednesday, November 16, 2016
Categories: Projects

Multi-Scale Prediction of California Current Carbonate System Dynamics

Burke Hales, Oregon State University

The California Current is a dynamic eastern boundary system that spans the Northeast Pacific from Canada to Baja California, Mexico. Upwelling of cold, nutrient rich water drives multi trophic level productivity throughout much of the domain, but also results in naturally acidic on-shelf waters on regional scales. In addition, anthropogenic CO2 on basin to global scales, and local inputs by eutrophication, fresh water inputs, and local respiration or carbon assimilation result in multiscale and context-specific perturbations to the carbonate system. Thus, to understand, manage, or mitigate the effect of ocean acidification on ocean ecosystems, we need to quantify a suite of carbonate system parameters along the Pacific Coast in a mechanistic, spatially explicit, and temporally dynamic fashion.

We propose to embed an improved semi-analytical carbonate-chemistry prediction model within a dynamic classification of pelagic seascapes derived from satellite remotely sensed variables, including, but not limited to, phytoplankton standing stock (chl-a), SST, and wind stress. We will produce synoptic time series and nowcasts of surface TCO2, TALK, pH and Ω that will facilitate regional comparisons of interannual trends in OA parameters. We will include metrics of model and spatiotemporal uncertainty to better inform management decisions. These maps will be validated with the wealth of multi-parameter OA data generated from recent NOAA-supported field-observational efforts, from coastal moorings, West-coast OA cruises, and shore-based Burke-o-Lators. Statistical analyses will quantify spatially explicit trends across OA parameters, and local deviations from seascape-based predictions will disentangle basin-scale oceanic vs. local drivers of the carbonate system. Maps will be served in near real time on IOOS data portals. Time series and maps will inform marine ecosystem management and provide metrics of ocean health for National Marine Sanctuary condition reports.

Wednesday, November 16, 2016
Categories: Projects

Evaluation of New Subsurface Carbon Technologies for OA Moorings

Adrienne Sutton and Chris Sabine, NOAA Pacific Marine Environmental Laboratory

The PMEL Carbon Group has been augmenting and expanding high-frequency observations on moorings to provide valuable information for better understanding natural variability in inorganic carbon chemistry over daily to inter-annual cycles. The current NOAA Ocean Acidification Observing Network (NOA-ON) consists of 21 moorings in coral, coastal, and open ocean environments. At present, the OA mooring network includes a standardized suite of surface sensors measuring for air and seawater partial pressure of CO2 (pCO2), pH, temperature (T), salinity (S), dissolved oxygen (DO), fluorescence, and turbidity at all sites. Although OA is primarily driven by uptake of CO2 from the atmosphere, many coastal and estuarine processes that affect water chemistry and the interpretation of coastal OA are manifested in subsurface waters. Furthermore, many of the most sensitive organisms (e.g. corals, shellfish) are benthic and respond to subsurface water chemistry. 

The Moored Autonomous pCO2 (MAPCO2) systems currently used on the 21 OA moorings are uniquely adapted for surface only measurements. PMEL has demonstrated these MAPCO2 systems are compatible with and comparable to ship-based underway pCO2 systems and discrete validation measurements used in the NOA-ON.  However, similar standardized methods and technologies have not been evaluated for subsurface observations on the existing mooring network. Our project evaluates the best carbon system technologies to deploy in the subsurface, demonstrate the utility of these enhanced observations on the moorings, and make recommendations on how advanced technologies can be incorporated into the NOA-ON.

Wednesday, November 16, 2016
Categories: Projects

Sustained OA Cruise Observations

Richard Feely, NOAA Pacific Marine Environmental Laboratory

This project contributes to the NOAA objective to provide accurate and reliable data from sustained and integrated earth observing systems through research, development, deployment, and operation of systems to collect detailed carbonate chemistry measurements as a part of a hydrographic research cruises along the west coast.  The NOAA Ocean Acidification Monitoring Program along North American coastlines (Atlantic, Pacific, Gulf, and Alaskan) and in the global open ocean will focus on mapping and monitoring the distribution of key indicators of ocean acidification including carbon dioxide, pH, and carbonate mineral saturation states. The overarching goal of the program is to determine the trends in ocean acidification (OA) and to provide concrete information that can be used to address acidification issues. The detailed hydrographic research cruises that are planned to be conducted every four years along our coasts are essential for providing high-quality intercalibration data across the full suite of OA observing assets in coastal waters, including well-proven technologies such as the MAPCO2 moored CO2 system and underway pCO2 systems on ships-of-opportunity as well as developing technologies such as wave gliders and sensors for additional carbon parameters. 

The hydrographic cruise measurements facilitate the overall monitoring effort's ability to address the near-term performance measure of quantifying aragonite saturation state in the areas studied to within 0.2.  In addition, the recurring coast-wide cruises allow us a critical opportunity to assess OA conditions along the West Coast in a synoptic fashion.  Cruise-based observations have provided critical information for model validation that is facilitating the improvement of next-generation physical-biogeochemical models projecting OA conditions into the past and the future.

Wednesday, November 16, 2016
Categories: Projects