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Carbon Dioxide Removal

Mitigating Ocean Acidification

View NOAA’s Carbon Dioxide Removal Research Strategy >

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What is Carbon Dioxide Removal?

Carbon dioxide removal aims to remove carbon dioxide (CO2) from the atmosphere and store it on land, underground, or in the ocean. 

Carbon dioxide removal (CDR) aims to remove carbon dioxide (CO2) from the atmosphere and store it long-term underground or in the ocean. There are many techniques and strategies to remove CO2 from the atmosphere, some of which operate on land whereas others are in the ocean. Ocean-based methods are often referred to as marine CDR (mCDR). These techniques differ in their readiness for deployment and there are many unknowns about scalability, effectiveness, cost, and social and ecological impacts.

NOAA’s CDR Research Strategy presents the benefits and risks of different land-based and ocean-based techniques and NOAA assets available to assess them.

Marine CDR & Ocean Acidification

Some of the proposed mCDR approaches may have potential to mitigate ocean acidification. Learn more about how mCDR and ocean acidification are related and these approaches.

How is marine CDR related to ocean acidification?
While emissions reductions are the most direct, reliable, lasting, and effective way to mitigate ocean acidification, CDR methods that lower the concentration of CO2 in the atmosphere also have the potential to slow it. Some marine CDR methods may also improve local ocean conditions that support ecosystems and economies.
Leveraging existing processes
Several existing processes in wastewater treatment facilities, golf courses and coastal management could be augmented to also draw down carbon dioxide. Leveraging these resources and processes can buffer local effects of ocean acidification. NOAA’s ecological monitoring and research programs can help answer questions of effectiveness and scale for these approaches.
Alkalinity Enhancement
Alkalinity enhancement aims to increase the ocean’s CO2 storage capacity by changing the chemistry of the sea water to encourage greater absorption of CO2 from the atmosphere. This method converts CO2 to stable carbonate forms, which reduces ocean acidification. It could be a valuable, albeit slow, acidification mitigation mechanism, but many unknowns around these techniques remain. NOAA has a well demonstrated ability to detect changes in ocean alkalinity and ocean carbon content on broad scales that can help evaluate concerns around these approaches.
Kelp Farming & Afforestation
Kelp farming or ocean afforestation uses the fast growth of kelp or other algae to capture CO2 from surface waters, potentially mitigating ocean acidification. Carbon in kelp tissue would then be stored in ocean sediments when kelp sinks to the bottom. While this may be a natural process to efficiently capture CO2, it may only have local or seasonal mitigating effects or benefits over short timescales. This approach may risk displacing existing phytoplankton productivity or produce other negative biogeochemical impacts. NOAA can provide modeling and observing capacity to assist siting and help answer questions about sequestration, storage, and impacts.
Valuable on Multiple Timescales
Even short-term or local-scale carbon removal could provide valuable benefits during times of heightened sensitivity by marine life or during episodic events. The scale, timing, and approach to carbon removal determines how effective it is at mitigating ocean acidification. NOAA has demonstrated expertise and assets to address many unknowns around the potential of ocean acidification mitigation by CDR.

NOAA's Investment in CDR Research

Schooling black jack fish behind coral reef

Why is NOAA investing in CDR research?

NOAA’s existing observational network and research programs position it to lead in the analysis of impact, effectiveness, feasibility, and risk of many CDR techniques. NOAA was created more than 50 years ago to study linkages between the ocean and atmosphere. Assessing the effectiveness of CDR approaches is directly related to its mission.

Read the Key Messages (PDF)

  • Voluntary carbon markets are increasing in value and there is potential for CDR to become over a trillion dollar industry by 2050.
  • Private industry is moving forward with carbon dioxide removal pilots. NOAA serves as a trusted agency to research and monitor efforts that can de-risk and provide integrity to this emerging market.
  • NOAA’s emphasis on big-picture, long-term monitoring and its existing research capabilities are ideally suited to understand, evaluate, and verify public and private entities’ exploration of CDR efforts and their potential for success.
  • NOAA's existing mandates, programs, and activities already intersect with CDR research.

Strategy for NOAA Carbon Dioxide Removal Research
NOAA’s CDR research strategy outlines what we know about existing technologies and what we need to learn to make the best decisions moving forward to meet climate goals. 

NOAA can contribute to advancing our understanding through: 

  • Coastal observing networks and data assimilation
  • Modeling, scaling & projecting CDR pathways
  • Ecosystem research & assessing impacts
  • Decision support

Carbon Dioxide Removal Projects

Click here to Read about recent mCDR projects.

Click here to view mCDR Projects
Fisherman pulling up sugar kelp. Seaweed cultivation may be one avenue for marine carbon dioxide removal and mitigating ocean acidification. Credit: GreenWave/Ron Gautreau.
Carbon capture and ocean acidification mitigation potential by seaweed farms in tropical and subtropical coastal environments
  • PI(s): Andreas Andersson
  • Fiscal Year Funded: 2023, 2024, 2025
  • Grant Award # NA23OAR0170512
This project will explore the carbon capture capacity and ocean acidification mitigation in three operational seaweed farms in Florida and Okinawa, Japan...
Project Summary >
Plankton bloom seen from space. Credit: NASA
Multiscale observing system simulation experiments for iron fertilization in the Southern Ocean, Equatorial Pacific, and Northeast Pacific
  • PI(s): Dennis McGillicuddy
  • Fiscal Year Funded: 2023, 2024, 2025
  • Grant Award # NA23OAR0170514
This project will address the effectiveness of ocean iron fertilization as a carbon dioxide removal technique, identify potential unintended ecological consequences, and determine the necessary systems for monitoring carbon and..
Project Summary >
Breaking wave in sunlight. Credit: NOAA Ocean Service
Electrolysis-driven weathering of basic minerals for long-term ocean buffering and CO2 reduction
  • PI(s): Burke Hales
  • Fiscal Year Funded: 2023, 2024, 2025, 2026
  • Grant Award # NA23OAR0170506
This project aims to demonstrate proof-of-concept that alkalinity addition and wave power systems could be used in tandem. The work will also informs a regulatory roadmap to highlight existing research..
Project Summary >

Carbon Dioxide Removal Resources

Fact Sheets

Carbon Dioxide Removal Fact Sheet

This State of the Science fact sheet explains the current status of carbon dioxide removal and various approaches to accomplish it. 

Download Resource
View More CDR Fact ShEETS

Reports

Cover for the output of the ICES / CIEM Workshop on Marine Carbon Dioxide Removal
Workshop on Marine Carbon Dioxide Removal (Outputs from 2024 Meeting)
Cover for NOAA CDR Research Strategy
Strategy for NOAA Carbon Dioxide Removal Research
View More CDR Reports

CDR Graphics Gallery

Infographic for CDR Strategy

This gallery is a collection of graphics from the NOAA Carbon Dioxide Removal Research Strategy that demonstrate various approaches of carbon dioxide removal.

View CDR Gallery

Other Resources

mCDR PI Meeting - Measurement, Monitoring, Reporting, and Verification (MMRV) Panel
2024 NOPP mCDR Meeting: Measurement, Monitoring, Reporting, and Verification (MMRV) Panel
mCDR PI Meeting - Permitting Panel
2024 NOPP mCDR Meeting: Permitting Panel
mCDR PI Meeting - Data Management Panel
2024 NOPP mCDR Meeting: Data Management Panel
2024 mCDR PI meeting - Social & Ethical Considerations Panel
2024 NOPP mCDR Meeting: Social and Ethical Considerations
View More CDR Resources

Get involved with ocean acidification

The NOAA Ocean Acidification Program exists to meet the ocean acidification research and monitoring needs of the U.S. See how you can get involved to serve your community and participate in cutting-edge research and education and outreach. 

Current Funding Opportunities

ADAPTING TO OCEAN ACIDIFICATION

The NOAA Ocean Acidification Program (OAP) works to prepare society to adapt to the consequences of ocean acidification and conserve marine ecosystems as acidification occurs. Learn more about the human connections and adaptation strategies from these efforts.

Adaptation approaches fostered by the OAP include:

FORECASTING

Using models and research to understand the sensitivity of organisms and ecosystems to ocean acidification to make predictions about the future, allowing communities and industries to prepare

MANAGEMENT

Using these models and predictions as tools to facilitate management strategies that will protect marine resources and communities from future changes

TECHNOLOGY DEVELOPMENT

Developing innovative tools to help monitor ocean acidification and mitigate changing ocean chemistry locally

REDUCING OUR CARBON FOOTPRINT

50 more ways to reduce your carbon footprint >

On the Road

Drive fuel-efficient vehicles or choose public transportation. Choose your bike or walk! Don't sit idle for more than 30 seconds. Keep your tires properly inflated.

With your Food Choices

Eat local- this helps cut down on production and transport! Reduce your meat and dairy. Compost to avoid food waste ending up in the landfill

With your Food Choices

Make energy-efficient choices for your appliances and lighting. Heat and cool efficiently! Change your air filters and program your thermostat, seal and insulate your home, and support clean energy sources

By Reducing Coastal Acidification

Reduce your use of fertilizers, Improve sewage treatment and run off, and Protect and restore coastal habitats

TAKE ACTION WITH YOUR COMMUNITY

You've taken the first step to learn more about ocean acidification - why not spread this knowledge to your community?

Every community has their unique culture, economy and ecology and what’s at stake from ocean acidification may be different depending on where you live.  As a community member, you can take a larger role in educating the public about ocean acidification. Creating awareness is the first step to taking action.  As communities gain traction, neighboring regions that share marine resources can build larger coalitions to address ocean acidification.  Here are some ideas to get started:

  1. Work with informal educators, such as aquarium outreach programs and local non-profits, to teach the public about ocean acidification. Visit our Education & Outreach page to find the newest tools!
  2. Participate in habitat restoration efforts to restore habitats that help mitigate the effects of coastal acidification
  3. Facilitate conversations with local businesses that might be affected by ocean acidification, building a plan for the future.
  4. Partner with local community efforts to mitigate the driver behind ocean acidification  – excess CO2 – such as community supported agriculture, bike & car shares and other public transportation options.
  5. Contact your regional Coastal Acidification Network (CAN) to learn how OA is affecting your region and more ideas about how you can get involved in your community
       More for Taking Community Action