The climate crisis has necessitated a wave of bold innovation. As new climate mitigation strategies have been developed, the law has often failed to keep up. This is especially clear in the ocean, where marine carbon dioxide removal (mCDR) projects – techniques that use the ocean to remove and store carbon dioxide from the atmosphere – are advancing amid regulatory uncertainty. This blog is intended as a primer and to provide context for the upcoming Columbia Law School mCDR law and policy symposium taking place on September 19, 2025.
The gap between innovation and regulation came into sharp focus in 2012, when a Canadian-based group – the Haida Salmon Restoration Corporation – discharged 100 tonnes of iron into the Pacific Ocean in an unsanctioned effort to stimulate a plankton bloom that would both sequester carbon and revive salmon populations. The project sparked both local and international controversy. At the time – and still today – scientists warned of unknown environmental risks, including potential disruptions to marine food chains and the carbon cycle. Legally, the project was in a grey area: the Canadian government conducted an investigation into possible illegal dumping, but ultimately decided not to take any action.
More than a decade later, the questions raised by that 2012 project have only grown more urgent. With the climate crisis accelerating and global efforts to cut emissions falling short, interest in carbon dioxide removal (CDR) technologies – including ocean-based approaches – is growing rapidly. The Intergovernmental Panel on Climate Change has said that CDR is “unavoidable” if we are to achieve net zero emissions. A 2022 report by the US National Academies of Sciences, Engineering, and Medicine (NASEM) found that “simply reducing the levels of human emissions may not be enough to stabilize the climate”, and that the ocean holds “great potential” for CO2 uptake and storage. mCDR methods are quite diverse and at various stages of development, ranging from growing seaweed to using electricity to drive reactions that remove carbon molecules from seawater.
Globally, the carbon removal industry is gaining traction. The global CDR market is projected to reach $134 billion by 2045, with over 140 companies already active across various approaches – including marine-based methods. In Washington State, Ebb Carbon is piloting electrochemical methods to enhance ocean alkalinity and thereby sequester carbon. Vesta, a San Francisco-based public benefit corporation, is conducting beach trials of enhanced weathering using olivine sand along the coasts of New York and North Carolina. In Canada, the Solid Carbon project is exploring the feasibility of capturing carbon dioxide offshore using direct air capture technology and to injecting it into subsea basalt off Vancouver Island. (The Sabin Center is a participant in the Solid Carbon Project).
While mCDR is being pursued in an effort to mitigate climate change, many techniques also pose risks to the environment and communities. These risks must be weighed against the projected catastrophic consequences of inadequate climate action. However, given the relatively early stage of research into many mCDR techniques and the significant unknowns they present, it is arguably too early to make that determination. Perhaps the question now is not whether mCDR should happen, but rather, how we can best regulate and set legal guardrails over mCDR to ensure responsible research and potential deployment.
Some environmental advocates and others remain deeply skeptical of mCDR. This is understandable given past experience with CDR on land. Efforts to advance afforestation and reforestation for CDR, for example, have faced controversies over land rights, biodiversity loss, and exploitation of the Global South. While some issues, such as accusations of neo-colonialism, are largely based on land territory contexts, many concerns over terrestrial CDR are also applicable to mCDR. Some worry that the mere promise of future mCDR could weaken the urgency of cutting emissions today, a dynamic known as “moral hazard.” Others point to the ecological risks of manipulating complex marine systems or to the potential for mCDR projects to exploit and harm vulnerable communities. The efficacy and verifiability of many mCDR methods remain deeply uncertain, leading to concerns about the potential for greenwashing, which has been observed in the afforestation context, where an analysis has shown that over 90% of rainforest carbon offsets certified by Verra are “worthless”.
mCDR also presents a distinct set of challenges that go beyond those of land-based carbon removal. The ocean is governed by overlapping domestic laws and international agreements, several of which are nonbinding or lack enforceability. Jurisdictional authority can be murky, especially in shared or transboundary waters, and questions of state, federal, tribal, and international responsibilities often remain unresolved. Compounding this is the ocean’s dynamic nature – unlike forests, ocean currents can carry the effects of an mCDR project across ecosystems and political boundaries, making monitoring, verification, and liability even more difficult.
While international discussions around mCDR governance have picked up in recent years, the legal framework remains fragmented and inadequate. The London Convention and Protocol adopted a 2013 amendment aimed at regulating activities like ocean fertilization, but it has yet to enter into force. Recent efforts have begun to explore how to govern newer mCDR approaches but so far have only produced non-binding guidance on two methods – ocean alkalinity enhancement and biomass sinking. There are signs, however, that parties to the London Convention and Protocol may be considering how these agreements can be adapted in the context of mCDR activities. For more information about the international legal framework for mCDR, see the Sabin Center’s previous posts here and here.
In the US, governance of mCDR activities currently fall under a patchwork of general environmental laws – such as the federal Clean Water Act (CWA), the Marine Protection, Research, and Sanctuaries Act (MPRSA), and the National Environmental Policy Act (NEPA) – that were developed long before the techniques existed. The application of these laws are often unclear, and can vary depending on the location and methods involved. At the same time, other projects may fall through regulatory cracks if they operate outside conventional definitions or jurisdictional boundaries. This ambiguity both burdens researchers and leaves room for risky or unregulated deployments.
In 2023, the Sabin Center for Climate Change Law published a model federal legislation which aims to both facilitate US-based mCDR research while ensuring it occurs safely and responsibly. The draft legislation draws a clear distinction between small-scale research and large-scale deployment, centralizes federal oversight under a lead agency, and calls for the development of a national research plan through an interagency working group. It emphasizes collaboration with state, tribal, and local governments via Regional Research Councils, which help shape regional priorities and advise on permitting. The legislation also designates specific zones for mCDR research to streamline review processes, requires permits for all research projects, and mandates meaningful public engagement. To ensure accountability, it allows the lead agency to require financial assurances for environmental cleanup.
This sort of regime, if adopted, would help to address many of the concerns surrounding mCDR – such as unintended ecological impacts, the potential for “geo-vigilantes”, and the risk of exploitation of vulnerable communities – while still allowing for exploration of mCDR’s role in the context of the climate crisis.
The upcoming Symposium on the Legal and Policy Dimensions of Marine Carbon Dioxide Removal aims to advance discussions about how to effectively regulate mCDR activities. The event will review the state of the science around mCDR, how it is currently regulated at the international level and domestically in the U.S., and what reforms might be needed or helpful.
As the fight for our planet continues, we must investigate every potential tool in our arsenal – but we have to do it right, with strong safeguards to protect both our oceans and our communities.
Great Job Patree Witoonchart & the Team @ Climate Law Blog Source link for sharing this story.
