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.
When the ocean absorbs carbon dioxide, chemical reactions create hydrogen ions that act like free agents, able to react with other compounds. Two ways we track ocean acidification are through pH and total alkalinity (TA). pH is a measure of how many free hydrogen ions are in the seawater. The more carbon dioxide in the ocean, the more these free agents are created, causing lower pH (more acidic).
The partial pressure of CO2 (pCO2) tells us how much carbon dioxide is in seawater. This information helps us understand ocean carbonate chemistry and biological productivity in the region. pCO2 increases when the ocean absorbs more CO2 from the atmosphere with elevated emissions.
Alkalinity is the ocean’s buffering system against increasing acidity. Total alkalinity is a measure of the concentration of buffering molecules like carbonate and bicarbonate in the seawater that can neutralize acid.
Dissolved inorganic carbon (DIC) tells us how much non-biological carbon is in seawater. Inorganic carbon comes in three main forms that we measure for DIC: carbon dioxide (CO2), bicarbonate (HCO3-), and carbonate (CO32-). Understanding DIC can help us determine the balance of carbonate forms in the ocean and the likelihood of ocean acidification.
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
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 (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).
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.
Community Sampling and Ocean Acidification Observations in South-central Alaska
Why we care
Southeast Alaska experiences ocean acidification at a faster rate than other regions due to its cold water temperatures and ocean current patterns. Indigenous communities rely on a healthy marine ecosystem and the culturally and economically important species that are impacted. This long-term community science monitoring program brings together scientists, aquaculturists, and seven Alaska Native communities to build capacity. This project brings awareness about the program, ocean acidification, and its impacts through multimedia.
What we are doing
The CRRC created a video in partnership with Alutiiq Pride Shellfish Hatchery (APSH) to communicate the scientific findings of a long term Native Alaskan community science water quality program south-central Alaska. The goals of the video are educating and raising awareness of ocean acidification and the community science monitoring program to Alaskan Natives and communities the CRRC serves. The video delivers the main findings of the program, highlights the partners and points to current and future impacts to wild shellfish and traditional subsistence food in the Chugach region.
Benefits of our work
This monitoring program serves as an example of co-producing science with indigenous communities that can be used nationwide. The video provides long-term water quality and ocean acidification monitoring data in a more meaningful storytelling format for coastal Alaska Native communities impacted by changing ocean conditions. By using different science communication techniques, such as through multimedia projects, the CRRC and APSH can reach more communities that may be interested in starting a water quality monitoring program in their local marine ecosystem.
NOAA OAP convenes community meeting in San Diego, CA!
Every three years, the NOAA Ocean Acidification Program convenes researchers, communicators and others in the OA community for a meeting to discuss and share the latest research and future needs and directions. We want your participation! Registration is free.
Shape the future strategic direction of the OAP
Inform community members of recent OAP-supported efforts
Foster collaborations within the OA research community
Identify critical research gaps and efforts to address them
Highlight and discuss diversity, equity, inclusion, accessibility, and justice in OA research and our community
Find more details and register HERE.
Assessing ocean acidification as a driver for enhanced metals uptake by Blue mussels (Mytilus edulis): implications for aquaculture and seafood safety
Why we care
Ocean acidification causes changes in the chemistry of stressors such as metals and may affect both the susceptibility of these animals to the contaminants as well as the toxicity. This is especially important for animals like blue mussels and other economically important shellfish that accumulate toxins in their bodies. Metal accumulation as a co-stressor of ocean acidification is not well documented for northeastern U.S. shellfish aquaculture species and better understanding these relationships supports seafood safety.
What we are doing
This work investigates the impacts of metal speciation (forms) on blue mussels under acidified conditions in both field and laboratory experiments. Scientists will first study uptake rates of these metals by blue mussels and then see how changing conditions affects their accumulation and toxicity. Comparing what they learn in the lab to what occurs in the field where these mussels are farmed, helps support decisions for seafood safety and industry best practices.
Benefits of our work
Coastal managers and aquaculturists can use these results that provide the societal benefits of better informed siting of aquaculture and safer seafood.