FAQs about the LOC-NESS Project

Ocean alkalinity enhancement (OAE) leverages a natural process to remove carbon dioxide from the atmosphere by adding an alkaline solution to the sea surface. The ocean’s pH (level of acidity/alkalinity) governs its ability to take up the greenhouse gas carbon dioxide from the atmosphere. In fact, the ocean has naturally absorbed as much as one-quarter to one-third of human emissions since the dawn of the Industrial Age. The ocean’s capacity to take up heat and carbon from the atmosphere helps regulate the climate system and has prevented much greater temperature increases over the past century. But this has also caused the ocean to gradually acidify, potentially causing severe impacts to species and ecosystems worldwide.  

While emission reductions are key to minimizing human impact on Earth’s climate, it has become clear in recent years that drastic emission reductions must be supplemented by efforts to actively remove existing carbon dioxide from the atmosphere in order to meet internationally accepted targets outlined in the Paris Climate Agreement and reaffirmed at the conclusion of the COP28 UN climate conference in Dubai.  

Adam Subhas, an associate scientist at Woods Hole Oceanographic Institution (WHOI), is the principal investigator leading the LOC-NESS project—short for Locking away Ocean Carbon in the Northeast Shelf and Slope—that aims to investigate OAE’s potential to help mitigate the effects of human-caused climate change by accelerating the ocean’s ability to remove carbon dioxide from the atmosphere without exacerbating ocean acidification.

The goal of LOC-NESS is to: (1) Understand potential environmental impacts of using ocean alkalinity enhancement to remove carbon dioxide from the atmosphere; and (2) Verify and report the amount of carbon dioxide this method might realistically remove if deployed at scale. The addition of an alkaline solution to seawater as part of OAE could also counteract localized ocean acidification driven by increases of atmospheric carbon dioxide concentrations.  

At the same time, there is also concern that commercial interests will enact a large-scale OAE effort to reap financial gain in the growing carbon market without first testing its safety and effectiveness. For that reason, the LOC-NESS team is undertaking a limited, highly monitored experiment to test OAE’s ability to take up atmospheric carbon dioxide as a small scale that minimizes any potential impact to the environment. 

While emission reductions are key to minimizing human impact on Earth’s climate, it has become clear in recent years that emission reductions must be supplemented by efforts to actively remove existing carbon dioxide from the atmosphere to meet internationally accepted targets outlined in the Paris Climate Agreement and reaffirmed at the conclusion of the COP28 UN climate conference in Dubai.  

Current technology cannot meet these goals, and new tools and processes are needed to remove carbon dioxide from the atmosphere. Ocean alkalinity enhancement could enhance the ocean's natural mechanisms for removing carbon from the atmosphere. OAE alone will not be enough, but it may be one of the many tools applied at scale if it can be demonstrated to be both safe and effective. 

There is also concern that commercial interests will pursue large-scale OAE efforts to sell carbon credits as part of the rapidly growing carbon market without first testing its safety and effectiveness at scale. For that reason, the LOC-NESS team is undertaking limited, highly monitored independent experiments to test OAE’s ability to take up atmospheric carbon dioxide at scale without long-term harm to the ocean or the people and organisms that rely on it. 

LOC-NESS is funded through a collection of non-profit, government, and private sources. The major philanthropic funders include the Carbon-to-Sea Initiative, which was recently launched to accelerate the understanding of OAE, and ICONIQ Impact, ICONIQ Capital’s platform for collaborative philanthropy, which searches for overlooked, underfunded organizations working on some of the most intractable challenges facing humanity and has matched the funding from Carbon to Sea for the LOC-NESS project. Supplemental support from the National Ocean Partnership Program (NOPP) overseen by the National Oceanic and Atmospheric Administration (NOAA) will allow the project team to do enhanced environmental monitoring.  Private funders include Paul Salem, Chair of the WHOI Board of Trustees, who recently made a significant gift to accelerate ocean-based climate solutions, and the Lockhart Vaughn Foundation, among others.

LOC-NESS will not take funding from any group or individual that stands to profit from the eventual deployment of industrial-scale OAE efforts. For more, please read WHOI's Position on Research Independence and Integrity.

Rhodamine WT will act as a proxy for the alkalinity deployment and is not considered toxic and is considered safe by the U.S Environmental Protection Agency (EPA) and Food and Drug Administration (FDA) in water tracing studies. It is particularly useful because small amounts of the dye are detectable in water using relatively simple instruments. The dye has been used for decades to study such things as the movement of pollution in freshwater and marine ecosystems and has been found to be safe for use in marine environments.

During the 2023 dye release field experiment, the Rhodamine WT was visible to the naked eye for several hours after the deployment. The science team also used instruments on the ship and towed through the water, as well as airborne drones, satellites, and a CTD rosette water sampler, to track the plume for 36 hours. They also surveyed the planktonic communities and water chemistry as background for later experiments.

While the alleviation of ocean acidification is a positive outcome of OAE, careful research is needed to determine safe operating thresholds for the addition of alkalinity to the marine environment and its impact on larger organisms such as copepods. During LOC-NESS field trials, the LOC-NESS project will operate within a pH range considered safe for aquatic life and will maintain strict environmental monitoring protocols. After alkalinity release, the team will undertake continuous, 24-hour monitoring operations of the alkalinity patch using a suite of instruments, sensors, and sampling equipment, guided by the results of the 2023 dye release trial and best scientific practices for OAE. The results of these monitoring efforts will provide some of the first in-water measurements of the safety of OAE, including its impacts on water chemistry, the marine food web, and larger organisms such as copepods.

For the dye-only field trial in summer of 2023, no permit was required, the water tracer used, called Rhodamine WT, is common in oceanographic studies.

The LOC-NESS Project is the first to apply for permitting for marine carbon dioxide removal activities through the EPA under the Marine Protection, Resources, and Sanctuaries Act (MPRSA). Our application is currently under consideration.

We are taking an intentional, transparent approach, communicating with key regional stakeholders—aquaculture, fishermen’s alliances, and conservation groups—and with federal agencies. Our website will provide regular updates on the project.

The dye-only trial the LOC-NESS team conducted in September 2023 was indispensable to our ability to plan for our upcoming alkalinity dispersal trials. An analysis of data gathered on the trial made our the monitoring strategy for our upcoming alkalinity trials more efficient and has allowed us to increase monitoring efforts in critical places. We had the chance to test all major equipment and gain practical experience in assessing the impacts of alkalinity enhancement in the open ocean. We also gained confidence that our methods are capable of tracking a patch of alkalinity enhanced water well after we are no longer able to measure changes in alkalinity and the water has returned to baseline conditions.

We first postponed the Phase 1 field trials south of Cape Cod from August to September 2024 to allow for a longer public comment period to our EPA permit application. We then postponed the trial to 2025 due to a mechanical issue with another ship in the US academic fleet, which caused the ship we had originally reserved to be diverted to another project.

Pending permission from the Environmental Protection Agency, the team plans to hold the first field trial in Federal waters south of Massachusetts. A subsequent field trial is planned for the Federal waters of the Wilkinson Basin in the Gulf of Maine.

The locations and timing of the field trials were selected based on three different factors:

• Ocean chemistry and physics: Northern oceans are relatively acidic, making them particularly well suited to OAE studies. The specific locations and timing were also selected to minimize environmental impact and to increase the amount of time the enhanced alkalinity remained in the surface seawater layer due to natural summer stratification that occurs here.  
• Favorable logistics: These regions are easily accessible by oceanographers at WHOI as well as commercial dispersal vessels.
• Existing Research: These two sites have been the location of highly relevant previous research that provide valuable baseline scientific information for these field trials.   

Model studies and direct measurements of the ocean currents in both locations indicate that the most likely surface current in the area will be directed away from land.  

The first phase field trial will consist of one controlled and monitored dispersal of up to 20 metric tons of sodium hydroxide (added as a 50% solution in freshwater totaling ~6,600 gallons) and ~75 kg Rhodamine water tracer dye (dissolved in fresh water). This will be followed by 3-5 days of on-site, continuous, 24-hour monitoring of alkalinity dispersal, carbon dioxide uptake, and environmental impacts. Dispersal will take place on the first day of the trial, over roughly 2-3 hours. These amounts are required to establish a patch of seawater with elevated alkalinity that can tracked for several days and potentially measure carbon dioxide uptake over the ~3-5 day experiment, while remaining within federal and state established water quality limits. As an analogy, our proposed alkalinity addition is equivalent to adding a teaspoon of liquid to a full bathtub.

The second phase, larger field trial will consist of one controlled and monitored dispersal of up to 200 metric tons of sodium hydroxide (added as 66,000 gallons of 50% solution in fresh water) and up to 750 kg Rhodamine dye, followed by up to 15 days of on-site, continuous, 24-hour monitoring of alkalinity dispersal, carbon dioxide uptake, and environmental impacts. The dispersal will be a one-time event lasting roughly 6-12 hours. The scale of this experiment is contingent on the results from the previous trials, the ability for the team to track the plume, and any additional constraints from the environmental impact assessment.

The larger amount is a 10x scaling from the initial experiment, which is necessary to demonstrate the scalability of release and of the associated CO₂ and environmental MRV (Monitoring, Reporting, and Verification) methodologies established through this project.

Our experiments employ high-purity sodium hydroxide (NaOH) to adjust the pH and alkalinity of the sea surface. The material is colorless, odorless and, when dissolved in fresh water, minimizes potential impacts of other alkalinity sources (increased particles and turbidity, interference with larger organisms, heavy metal byproducts). Because of its purity, the effects on water quality are limited only to the effect on pH. Sodium hydroxide is commonly used in the United States by local municipalities to reduce the acidity of drinking water to levels that are safe for human consumption, and it does not bioaccumulate. It is regularly used in commercial and residential baking, for example, giving soft pretzels their characteristic brown shine.  

All of the monitoring approaches are based on the technical expertise of team members and are consistent with best practices for oceanographic research. Lead PI Subhas is a co-author of the recently published “Best Practices Guide for Ocean Alkalinity Enhancement Research,” which documents the current state of knowledge for conducting field experiments, biological and laboratory studies, and handling and analyzing samples of ocean alkalinity enhancement research.   

The alkalinity releases described here will be continuously monitored using state-of-the art scientific equipment and research vessels to establish the efficacy of carbon dioxide uptake via OAE and the extent of environmental impacts. The monitoring will continue well after the dispersal occurs, until alkalinity and dye is no longer detectable above baseline values. The second experiment will be larger in scale than the first, resulting in a more extensive and comprehensive monitoring phase with more platforms and personnel.   

The main variables measured include temperature, salinity, dissolved oxygen, pH, total alkalinity, pCO2, dye concentration, particulate matter composition and plankton community. The team will use a series of platforms that allow for deployment of different types of instrumentation and receive measurements back in real-time. A profiling vehicle will be towed behind the ship that will provide real-time, continuous data throughout the trial. Free-drifting buoys equipped with rhodamine dye, water quality sensors, and GPS will passively follow experimental progress, providing a secondary means to track the plume.  The ship’s underway pumped system will be outfitted with instruments that measure pH, alkalinity, pCO2, temperature, salinity, and dye concentration, allowing the ship to continuously measure surface water conditions during the survey. Drone and satellite imagery will show the extent of the dye and alkalinity patch at the surface. Water samples and plankton tows will be collected as part of the environmental impact monitoring. The monitoring plan will be adjusted in accordance with the information learned from the initial experiment. In addition to the above measurements, during the larger experiment, the team also plans to deploy sediment traps to measure the sinking flux of particulate matter out of the mixed layer. Autonomous underwater gliders will also be deployed in the Gulf of Maine to measure the background site pre-dispersal and monitor the dispersal and subsequent dilution. A suite of five Spray2 gliders will be deployed (and later recovered), equipped with a suite of sensors (temperature, salinity, oxygen, pH, rhodamine water tracer fluorescence and chlorophyll fluorescence) along with devices capable of measuring zooplankton distribution.   

Our field trial team will also include a trained protected species observer (PSO), who will keep continuous watch for protected and endangered species during the dispersal period of operations. If protected species are observed, the PSO will be able to halt dispersal operations until the protected species is no longer present in the area.

Based on lab studies, modeling, and field-based research, the effect of enhanced alkalinity as proposed in these field studies is predicted to be either mild or even positive for treated waters. The project will carefully mix in the sodium hydroxide so the seawater remains below pH 9, a limit established by the EPA (EPA “Gold Book”, 1986), within two minutes and will affect only a relatively small number of phytoplankton and zooplankton located directly in the discharge area. After the dispersal, the alkaline seawater will continue to dilute and mix into surrounding . After the dispersal, the alkaline seawater will continue to dilute and mix into surrounding waters, further reducing its pH, increasing its dilution, until it returns to a baseline state.

According to a review of our permit application by NOAA Fisheries, the effects on aquatic life susceptible to sudden pH changes will be “limited to an extremely short amount of time and have insignificant effects (not able to be meaningfully measured or detected) to adult and subadult Atlantic sturgeon, adult shortnose sturgeon, adult and juvenile leatherback, loggerhead, Kemp’s ridley and green sea turtles, adult and juvenile North Atlantic right and fin whales and their prey."

While previous studies indicate no significant impacts to the biological community, the effects of large-scale OAE on marine ecosystems during real-world deployments have not been evaluated. As a result, it is critical to validate these findings through in-water experiments so appropriate conditions can be put in place for larger OAE operations in the future. One potential outcome from our work is also that OAE may not be as effective in practice as it appears on paper. This is a perfectly reasonable outcome, and one that should be determined by rigorous independent, scientific monitoring by institutions like WHOI rather than a for-profit enterprise with a vested interest in the outcome of the experiment.

The LOC-NESS project is committed to open and transparent documentation of environmental impacts, and any impacts documented during the first trial will inform our dispersal and monitoring strategy in the next year. The project team sees this carefully monitored, real-world field trial as a necessary and critical part of evaluating marine CDR techniques.  Data and other project products will be made publicly available through the project website and through publicly available data repositories when manuscripts are published.  

No. Our initial field trial will occur more than 10 miles offshore, and the subsequent field trial will be significantly farther. Previous work on ocean currents in both regions suggests that the dispersed alkalinity and dye will move away from shore once in the ocean. 

In order for ocean alkalinity to be effective, it needs to stay in surface waters. The team does not expect the field trials to impact submerged resources such as benthic shellfish, submerged aquatic vegetation, cultural/archaeological sites, or other similar resources. The study will be confined to the upper 5-10 meters of the water column.   

The purpose of these field trial experiments is to determine the efficacy and environmental safety of OAE. Neither WHOI, nor the LOC-NESS project team endorse OAE as a climate mitigation strategy and do not have a financial stake in any for-profit effort to remove carbon dioxide from the atmosphere, as described in WHOI’s Position Statement on Marine Carbon Dioxide Removal. Showing OAE is not safe or effective will be just as important to share as a result demonstrating the promise of this technique to help guide future decisions about how to address climate change. LOC-NESS is committed to openly sharing the data collected through all aspects of this effort.

A general project email that is monitored daily is locness@whoi.edu.  

If you specifically need to reach out to the lead scientist, Adam Subhas, his email is asubhas@whoi.edu. An alternate would be the Project Manager, Kathryn Baltes, her email is kbaltes@whoi.edu.