Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Carbon Dioxide Removal

Mitigating Ocean Acidification and Climate Change

View NOAA’s Carbon Dioxide Removal Research Strategy >

Jump to Section

What's New

See our most recent news related to carbon dioxide removal

NOAA’s Ocean Acidification Program seeks qualified candidates for four postdoctoral positions to synthesize data in the major areas of the program’s investments.

NOAA OAP selects, funds, and manages high priority, high-quality research, monitoring, and outreach activities to understand how fast the acidification is changing, and impacts these changes have on marine life, people, and economies. Check out some of the 2023 accomplishment highlights.

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), also referred to as negative emissions or carbon drawdown, aims to remove carbon dioxide (CO2) from the atmosphere and store it long-term underground or in the ocean. In addition to curbing emissions, CDR is now considered by the Intergovernmental Panel on Climate Change an essential approach for limiting global warming to 1.5 – 2 °C, which is a tipping point with expected major, irreversible ecological and social impacts. 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

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.
Coastal Blue Carbon
Coastal blue carbon’ is carbon sequestered and stored in coastal wetlands like natural salt marshes, mangroves, and seagrasses. Conserving and restoring seagrass meadows can buffer local effects of ocean acidification, and may have limited ability to address global impacts. NOAA’s ecological monitoring and research programs can help answer questions of effectiveness and scale for this approach.
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.
Previous slide
Next slide

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.

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

Fisherman pulling up sugar kelp. Seaweed cultivation may be one avenue for marine carbon dioxide removal and mitigating ocean acidification. Credit: GreenWave/Ron Gautreau.
This project will explore the carbon capture capacity and ocean acidification mitigation in three operational seaweed farms in Florida and Okinawa, Japan...
Plankton bloom seen from space. Credit: NASA
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..
Breaking wave in sunlight. Credit: NOAA Ocean Service
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..

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. 

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.

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. 

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

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

Previous slide
Next slide

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