Understanding the exposure of the nation’s living marine resources such as shellfish and corals to changing ocean chemistry is a primary goal for the NOAA OAP. Repeat hydrographic surveys, ship-based surface observations, and time series stations (mooring and ship-based) in the Atlantic, Pacific, and Indian Oceans have allowed us to begin to understand the long-term changes in carbonate chemistry in response to ocean acidification.

Buoys & Moorings

There are currently 19 OAP-supported buoys in coastal, open-ocean and coral reef waters which contribute to NOAA's Ocean Acidification Monitoring Program, with other deployments planned.

Currently, there are two types of floating devices which instruments can be added in order to measure various ocean characteristics - buoys and wave gliders. Buoys are moored, allowing them to remain stationary and for scientists to get measurements from the same place over time. The time series created from these measurements are key to understanding how ocean chemistry is changing over time. There are also buoys moored in the open-ocean and near coral reef ecosystems to monitor the changes in the carbonate chemistry in these ecosystems. The MAP CO2 sensors on these buoys measure pCO2 every three hours.

Access our buoy data


Ship surveys

Research cruises are a way to collect information about a certain ecosystem or area of interest.

For decades, scientists have learned about physical, chemical and biological properties of the ocean and coasts by observations made at sea. Measurements taken during research cruises can be used to validate data taken by autonomous instruments. One instrument often used on research cruises is a conductivity, temperature, and depth sensor (CTD), which measures the physical state of the water (temperature, salinity, and depth). The sensor often goes in the water on a rosette, which also carries niskin bottles used to collect water samples from various depths in the water column. Numerous chemical and biological properties can be measured from water collected in niskin bottles.

Ships of Opportunity

Ships of Opportunity (SOPs) or Volunteer Observing Ships (VOSs) are vessels at sea for other reasons than ocean acidification studies, such as commercial cargo ships or ferries.

The owners of these vessels allow scientific instrumentation that measures ocean acidification (OA) parameters to be installed and collect data while the ship is underway. This allows data on ocean chemistry to be collected in many remote areas of the world's ocean, such as high latitude waters, long distances from land (e.g. mid-basin waters), and places not easily accessible by research cruises. These partnerships have greatly increased the spatial coverage of OA monitoring world-wide. To learn more, check out the Ships of Opportunity programs established by the NOAA Pacific Marine Environmental Laboratory (PMEL) and the NOAA Atlantic Oceanographic Marine Laboratory (AOML).

Wave Gliders

Scientists at the NOAA Pacific Marine Environmental Laboratory (PMEL) are working with engineers at Liquid Robotics, Inc. to optimize a Carbon Wave Glider.

This instrument (pictured above) can be driven via satellite from land. Carbon Wave Gliders can be outfitted with pCO2, pH, oxygen, temperature and salinity sensors, and the glider’s equipment takes measurements as it moves through the water. The glider’s motion is driven by wave energy, and its sensors are powered through solar cells and batteries, when needed.


NOAA’s Coral Reef Conservation Program (CRCP) in partnership with OAP is engaged in a coordinated and targeted series of field observations, moorings and ecological monitoring efforts in coral reef ecosystems.

These efforts are designed to document the dynamics of ocean acidification (OA) in coral reef systems and track the status and trends in ecosystem response. This effort serves as a subset of a broader CRCP initiative referred to as the National Coral Reef Monitoring Plan, which was established to support conservation of the Nation’s coral reef ecosystems. The OAP contributes to this plan through overseeing and coordinating carbonate chemistry monitoring. This monitoring includes a broadly distributed spatial water sampling campaign complemented by a more limited set of moored instruments deployed at a small subset of representative sites in both the Atlantic/Caribbean and Pacific regions. Coral reef carbonate chemistry monitoring is implemented by researchers at the NOAA Atlantic Oceanographic & Meteorological Laboratory (AOML) and NOAA's PIFSC Coral Reef Ecosystems Division.




Physiological response of commercially important crab species to predicted increases in carbon dioxide

Bob Foy, NOAA Alaska Fisheries Science Center

In 2010 and 2011, Alaska Fisheries Science Center (AFSC) scientists at the Kodiak Laboratory in Alaska tested the effects of lower pH due to increased carbon dioxide (CO2) on the survival, condition, and growth of red king crab (Paralithodes camtschaticus). Commercially important shellfish are a priority for AFSC research related to ocean acidification because of their economic value and because calcifying species are likely to suffer direct effects due to increased acidity (and a decrease in calcium carbonate saturation state) of our oceans.

The multi-year project objectives are to test the effects of CO2 enrichment (which leads to decreasing pH and lower saturation state) across a range of commercially important crab species and life stages (embryo, larvae, juveniles, and adults). The response variables currently measured include mortality, condition, growth, and calcification of the shell.

Wednesday, November 16, 2016
Categories: Projects

Assessing the capacity for evolutionary adaptation to ocean acidification in geoduck

Rick Goetz, NOAA Northwest Fisheries Science Center

We will examine the effects of OA conditions (elevated pCO2) on the adaptive response of a potentially vulnerable native marine mollusc species with ecological, economic and social importance in the Pacific Northwest: geoduck clams (Panopea generosa).  Geoduck clam larvae will be exposed to normal and elevated pCO2 and surviving larvae will be assessed using genomic sequencing to determine changes in allele frequencies at single nucleotide polymorphisms throughout the genome, and changes in the frequency of methylation states (epialleles) throughout the epigenome.  Existing ecosystem models of OA consider a species' response to increased pCO2 as a fixed attribute; however, interpretations of the effects of OA at the population level may shift substantially if species adapt to the new environment. Furthermore, we will gain a better understanding of how specific genetic and epigenetic variations influence phenotype and the ability of an organism to respond, giving us new insights into fundamental aspects of species adaptation to environmental change.

Wednesday, November 16, 2016
Categories: Projects

Zooplankton OA Exposure Modeling

Paul McElhany, NOAA Northwest Fisheries Science Center

Assessing a species’ risk to ocean acidification (OA) will depend on their duration of exposure to low pH/low saturation state conditions and their sensitivity to low pH conditions. Lab species exposure experiments attempt to measure species sensitivity to low pH. This modeling project estimates species exposure. In FY13, we started using an existing circulation/water quality of model of the Salish Sea and Washington/B.C. Coasts developed by the Pacific Northwest National Laboratory to understand carbonate chemistry exposure of zooplankton species. We are using empirical relationships between carbonate chemistry, oxygen, temperature and salinity to add carbonate chemistry to the circulation model. We then use an individually-based model to simulate the movement of various zooplankton species in this environment. In FY15-FY17, we will continue development and publication of results from this model, including exploration of current and future CO2 scenarios. Results from the model will inform the Dungeness crab exposure experiments planned for FY16, as well as general zooplankton vulnerability to OA.

Tuesday, November 8, 2016
Categories: Projects

OA Ecosystem Modeling

Paul McElhaney, NOAA Northwest Fisheries Science Center

Ecosystem models are used to estimate the potential direct and indirect effects of ocean acidification (OA) on marine resources.  The population abundance and distribution of species that are sensitive to seawater carbonate chemistry can experience the direct effects of OA. Even species not sensitive to carbonate chemistry can have indirectly changes in abundance and distribution as a result of changes in their prey, predators, competitors or critical habitat forming organisms that are sensitive. Ecosystem models use information on food webs and other relationships to estimate these ripple effects of OA on important ecosystem services like fisheries.

Tuesday, November 8, 2016
Categories: Projects


Species exposure experiments that measure the response of organisms reared in seawater with manipulated carbonate chemistry are an important way to learn about the potential effects of ocean acidification (OA). Experimental systems that closely mimic the natural environment (e.g. with multiple stressors) can lead to studies with greater ecological relevance. Using a combination of NWFSC and OAP funds, the NWFSC built a facility for conducting species exposure experiments at the Montlake Lab, and has started a new facility at the Mukilteo Field station. The facilities include both rearing aquaria and a lab for carbon chemistry analysis (DIC, alkalinity, spectrophotometric pH). The NWFSC experimental systems are considered “shared-use” facilities, in that the systems are available for NWFSC research teams and outside collaborators as capacity allows. In the past, we have worked on collaborative projects with PMEL, University of Washington, Oregon State University, Suquamish Tribe, Evergreen State University, Cal Poly and Western Washington University. These collaborators often provide external funding for experiments, greatly increasing the research that can be conducted.

Tuesday, November 8, 2016
Categories: Projects