With the planet at a critical crossroads for climate change, reducing atmospheric carbon dioxide has become increasingly urgent. There is growing interest in harnessing the ocean’s natural ability to store carbon, including engineered climate interventions like marine carbon dioxide removal (mCDR). However, several fundamental questions remain about the effectiveness of mCDR. Scientists and industry leaders need a framework for monitoring, reporting, and verifying carbon dioxide removal in order to bring ocean-based climate interventions to the market.

In a partnership with Woods Hole Oceanographic Institution (WHOI) and MRV Systems, LLC, next-generation chemical sensors developed by MBARI engineers will be integrated with autonomous robots. Pairing these technologies may offer a more nimble and cost-effective option for evaluating mCDR. The team will test this new strategy during an upcoming mCDR field experiment in the Gulf of Maine in 2025.

“We urgently need to reduce atmospheric carbon dioxide. While there’s no substitute for deep emissions cuts, engineered climate interventions are likely to be an important part of our climate solutions toolkit. MBARI is eager to be part of this collaborative effort to help develop the monitoring, reporting, and verification tools needed to advance any potential climate solution that harnesses the power of the ocean to store carbon dioxide,” said Yui Takeshita, who leads MBARI’s Ocean Biogeochemical Sensing (OBS) Team and is a co-principal investigator on this new collaboration.

As the largest natural sink for carbon, the ocean and its inhabitants have already buffered our planet from the impacts of climate change. However, global temperatures continue to rise, with serious ecological and economic consequences. The ocean may be our ally again, holding potential pathways for removing carbon dioxide from the atmosphere. But before we can pursue marine carbon dioxide removal (mCDR), we need a framework for determining how safe, effective, and durable these efforts are.

New federal funding from NOAA will allow MBARI and collaborators from WHOI and MRV Systems to join an upcoming field test of mCDR and deploy a fleet of robotic gliders equipped with MBARI’s chemical sensors to evaluate how scientists and industry can best leverage autonomous technology to monitor future carbon removal efforts.

“MBARI is excited to partner with WHOI and MRV Systems to develop tools to better monitor the efficacy and impacts of ocean-based carbon removal. We’ll bring MBARI’s engineering expertise to equip innovative underwater gliders with chemical sensors that can measure carbon uptake by the ocean. This collaborative effort will ultimately provide a cost-effective framework to assess various ocean-based solutions for removing atmospheric carbon dioxide,” said Takeshita.

In 2025, WHOI researchers will conduct the first large-scale field trial of ocean alkalinization, a type of mCDR that uses alkaline materials, like minerals, to jumpstart the ocean’s natural absorption of carbon dioxide. The WHOI team will monitor this field trial in the Gulf of Maine from research vessels using computer modeling to determine how much carbon dioxide is removed during the experiment and observing the associated ecological response.

MBARI has joined WHOI and MRV Systems to run a parallel test to determine how autonomous technology can be used to monitor mCDR efforts. 

“As mCDR approaches emerge, there is a huge need to develop robust methods for assessing their efficacy and ecosystem response. Underwater gliders equipped with sensors for carbon and ecosystem parameters can provide the distributed measurements needed to do so,” said WHOI Associate Scientist David Nicholson, the lead principal investigator on this project.

Traditional ship-based sampling requires a significant investment of resources. Increasingly, nimble autonomous robots have provided scientists a cost-effective way to scale their research efforts. Robotic gliders are an especially useful tool for extended monitoring of marine environments.

Gliders use changes in buoyancy to move through the water. Computers inside the glider cause it to sink or rise toward the surface, creating a vertical profile of ocean conditions. As the glider rises or sinks, its wings provide lift that causes it to move forward. When the glider surfaces, a satellite connection sends data back to scientists on shore. Pilots on shore use the satellite connection to transmit instructions for the glider’s next mission. Gliders can stay at sea for months at a time. These robots have played an integral role in sustained scientific observations of the coastal ocean. 

MBARI’s Ocean Biogeochemical Sensing Team is developing sensors to better understand the ocean’s changing chemistry. Working closely with MBARI’s Chemical Sensors Team, they are deploying autonomous robots, like gliders, to measure and monitor these changes to understand how climate change affects ecosystems from the coast to the open sea.

MBARI scientists and engineers have developed sensors that can precisely measure ocean pH, or the acidity of seawater. pH is closely tied to carbon dioxide chemistry in the ocean, so these sensors can provide important information about biogeochemical processes. This technology is already in use aboard robotic floats like MBARI’s Coastal Profiling Float and a fleet of biogeochemical (BGC) Argo floats deployed by the Global Ocean Biogeochemistry Array (GO-BGC) and Southern Ocean Carbon and Climate Observations and Modeling (SOCCOM) project. 

Now, the MBARI teams have created a smaller, more power-efficient pH sensor that can be used in a variety of ocean-going platforms, not just floats. Leveraging MBARI engineering expertise, the project will outfit a fleet of five Spray2 gliders—a second-generation glider developed by the Scripps Institution of Oceanography Instrument Development Group and commercialized by MRV Systems—with these new pH sensors to observe upcoming mCDR interventions and independently assess carbon removal and ecosystem response. 

Before alkalinization gets underway, WHOI and MRV Systems will use the Spray2 gliders to characterize the conditions of the test site. The gliders will establish a biogeochemical baseline for the natural ebb and flow of carbon there. Once alkalinization gets underway, the gliders will track how much additional carbon is stored in the ocean, in conjunction with WHOI’s ship-based monitoring. 

This glider-based field program will lay the foundation for future experiments, and ultimately industry, to build upon as they look for ways to restore the climate and ocean health. The team hopes to gain insight into the ways autonomous technology can grow mCDR monitoring efforts and bring us toward a future where cost-effective monitoring, reporting, and verification can be achieved entirely by autonomous robots.

“MBARI technology is already transforming how we monitor ocean health at a global scale. Now, thanks to funding from NOAA and the National Oceanographic Partnership Program, our team will be able to integrate MBARI’s innovative chemical sensors with autonomous robots,” said Takeshita. “Working with our collaborators at WHOI and MRV Systems, we’ll deploy a fleet of autonomous robots to measure the effectiveness of an ocean-based carbon removal experiment in the Gulf of Maine. Given the urgent need to reduce carbon dioxide in the atmosphere, this work will help lay the foundation for emerging efforts to bring ocean-based solutions to the market.”

Funding for this work is provided by NOAA’s Ocean Acidification Program, on behalf of the National Oceanographic Partnership Program (NOPP), as part of a new large-scale public investment in research specifically focused on mCDR. This funding is aimed at bringing together academic researchers, federal scientists, and industry to advance research in mCDR. Findings from this work will assist in assessing the potential of mCDR for mitigating climate change. 

NOPP-funded mCDR projects support research that expands understanding of various aspects of marine carbon dioxide removal approaches; risks and co-benefits, including ocean acidification mitigation; and science needed to build regulatory frameworks for testing and scaling of marine carbon dioxide removal.

These projects focus on understanding uncertainties and knowledge gaps for different mCDR approaches including macroalgal cultivation, ocean alkalinity enhancement, enhanced weathering, and electrochemical approaches. The projects include lab experiments, modeling, field trials, and engaging communities to understand the impacts and effectiveness of various marine carbon dioxide removal strategies. Much of this work aligns with recommended research priorities of the NOAA Strategy for Carbon Dioxide Removal Research. 

NOPP has provided $24.3 million to fund 17 projects with partners from 47 institutions. 

The Inflation Reduction Act provided $14.36 million to fund 10 of the projects as part of the Investing in Coastal Communities and Climate Resilience provision under NOAA’s Integrated Ocean Observing System IRA priorities. This investment supports climate mitigation through research as part of President Biden’s Investing in America agenda. 

An additional $10 million provided by the NOAA’s National Oceanographic Partnership Program, Ocean Acidification Program and Global Ocean Monitoring and Observing Program, the Department of Energy’s Office of Fossil Energy and Carbon Management and Water Power Technologies Office, Office of Naval Research, National Science Foundation, and the ClimateWorks Foundation supports seven more marine carbon dioxide removal research projects.

Read a press release about this work from our collaborators at WHOI. Read NOAA’s press release about all NOPP-funded mCDR projects. For additional information or images relating to this news story, please email pressroom@mbari.org.