Climate ChallengesFeasibility, Cost, and Potential Impacts of Ocean-Based Carbon Dioxide Removal Approaches
To better understand the potential risks and benefits of removing or sequestering atmospheric carbon dioxide using ocean-based interventions — for example, by cultivating seaweed on a large scale or manipulating nutrients in seawater — the U.S. should undertake a new research program to learn more about how these methods could be used to mitigate the impacts of climate change.
To better understand the potential risks and benefits of removing or sequestering atmospheric carbon dioxide using ocean-based interventions — for example, by cultivating seaweed on a large scale or manipulating nutrients in seawater — the U.S. should undertake a new research program to learn more about how these methods could be used to mitigate the impacts of climate change, says a new report from the National Academies of Sciences, Engineering, and Medicine.
A Research Strategy for Ocean-Based Carbon Dioxide Removal and Sequestration says current levels of CO2 emissions greatly exceed the ability of nature to remove it from the environment, and reducing carbon emissions alone may not be enough to stabilize the climate. A 2019 National Academies report found that to meet climate goals, carbon dioxide removal technologies and strategies will need to remove roughly 10 gigatons of CO2 every year by 2050. While several land-based strategies — such as storing carbon in agricultural soil or changing forest management — may be ready for deployment, less is known about the risks, benefits, and trade-offs of implementing ocean-based strategies.
The new report recommends a $125 million research program to better understand overarching challenges for ocean-based CO2 removal approaches, including the potential economic and social impacts. This research should start now and continue over the next 10 years — systematically examining the trade-offs and interactions between ocean-based approaches with other negative emissions technologies, and with other climate change mitigation efforts.
The program should develop and adhere to a common code of conduct that emphasizes transparency and public engagement; improve understanding of the social impacts; set the stage for permitting and a new regulatory environment that could allow for responsible research; collaborate with Indigenous and other communities; and promote international cooperation in research and governance. This research should aim to develop an unbiased and improved base of knowledge about ocean-based CO2 removal for the public, stakeholders, and policymakers to use — not to advocate for or lock in deployment of any specific approach.
The committee that wrote the report also assessed six specific approaches, evaluating their efficacy, durability, scalability, potential environmental risks, social considerations, and how much is known about each so far, among other factors. For each approach, the report recommends research priorities and estimates the additional cost of the next steps for research over the next five to 10 years.
