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Advancing Research and Development of Marine Carbon Dioxide Removal: Ocean Visions, Running Tide, and the Role of Start-Ups


With the recent announcement of the shutdown of Running Tide, a Maine-based company working to sequester excess carbon dioxide in the ocean, there has been a swirl of speculation, inaccurate statements, and sweeping conclusions about why Running Tide closed its doors, and what this portends for the field of carbon dioxide removal (CDR) and for marine-based forms of carbon dioxide removal (mCDR) specifically.  

As a science-based ocean conservation organization that has worked with Running Tide for more than three years, as well as with 13 other mCDR startups through our Launchpad program, we hope to inform the discussion and the emerging lessons by sharing some background, our experiences with Running Tide, and some thoughts about the role of the private sector in research and development of mCDR.  


Ocean Visions works to accelerate and scale solutions to the biggest threat facing our ocean: the buildup of greenhouse gases in our atmosphere and ocean, which drives dangerous levels of ocean warming and acidification. Our collective societal failure to decarbonize at the levels required has left us with no choice but to massively scale CDR to about 10 billion tons per year by mid-century – at the same time as we dramatically increase decarbonization across all sectors of our economy. These two strategies combined are the only way to meet the temperature goals of the Paris Agreement. 

So we stand at the start of a collective race to build and scale the multibillion-ton-per-year CDR industry in the next 25 years. For perspective, 2023’s total carbon removals from “novel” sources, which are the technologies with the most new growth potential (including direct air capture, biochar, enhanced rock weathering, and mCDR), was only 1.3 million tons (0.0013 billion tons). Clearly, we have a long way to go. 

As we confront this reality, our focus needs to be on the biggest opportunities to reach scale, and the ocean must be on the list. Why? The ocean occupies more than 70 percent of the surface area of our planet, is the biggest part of the global carbon cycle, and mCDR pathways don’t require arable land, fresh water, or nutrients in the same way as other forms of CDR. Yet mCDR pathways remain underdeveloped for several reasons, foremost because it is much harder to operate in the ocean, and to measure carbon removal and environmental effects.  

Recognizing the potential and the questions about mCDR, Ocean Visions has worked to support and promote responsible research, development, and testing of all possible mCDR pathways to determine which solutions might be safe, effective, and viable.   

Our work is grounded in a series of research road maps we published during 2021-23. These maps assess the current state of development of five major domains of marine CDR; identify outstanding questions and barriers; and lay out a series of first-order priorities to answer fundamental remaining questions about efficacy and safety of each of the different mCDR pathways.  

One of the highest priorities across all the maps was to accelerate research, development, and demonstrations (RD&D) of each major pathway. Since the publication of the maps, we have seen a number of start-up companies play a significant role in advancing that needed RD&D. 

To support that research, we created a program called Launchpad in 2022 to provide independent scientific and engineering advice and evaluation to startups engaged in testing and adapting technologies and systems for mCDR. Ocean Visions selects innovative companies (we currently work with 13 companies across two cohorts) through a competitive application process. We then assemble customized teams of independent expert advisors sourced from our diverse Network and beyond to advise each company. These advisory teams meet regularly with the startups to review and advise on research, testing, and development plans with an eye towards maximizing technical rigor, technological performance, and minimizing environmental impact. Advisors do not provide any business advice to the startups, and there is no financial relationship with the companies. Ocean Visions provides the Launchpad advisory services free to selected companies, thanks to support from our donors. 

Ocean Visions and Running Tide 

Our work with Running Tide predates the creation of Launchpad and, in many ways, helped inspire Launchpad’s design. Ocean Visions first began working with Running Tide in 2021 when we convened a team of experts to evaluate and assess an earlier iteration of Running Tide’s proposed approach. The team provided feedback on system design and potential environmental impacts. That team eventually evolved in membership and became an independent Science Advisory Board (SAB) for Running Tide. Ocean Visions staff were not part of the SAB, but administered it, attended meetings, and helped the SAB liaise with Running Tide. The SAB met quarterly to provide feedback on key documents such as the Research Roadmap and Catalog of Potential  Environmental Procedures, which can be found here in Running Tide’s Research Portal.   

The SAB worked directly with a team of scientists and engineers on the staff of Running Tide. At one point in time, Running Tide had nine PhDs on staff ranging in disciplines from oceanography, atmospheric modeling, biogeochemistry, bioengineering, and biology – all involved in designing and leading experiments. In our experience, Running Tide’s team worked diligently to ensure that their research was well designed and scientifically robust. The SAB provided advice to the Running Tide team on how to design and run field experiments, such as their collaboration with Ocean Networks Canada to study the fate of organic materials in the deep ocean. This is the kind of experiment to address environmental impacts of mCDR that needs to be happening all over the world. 

Running Tide also contributed to collaborative efforts to advance collective knowledge. Running Tide showed up and sought to engage with the larger scientific community by presenting at scientific conferences. Running Tide staff joined the project working group to produce a macroalgae research framework that we published with MBARI in 2022. This framework laid out the necessary science and associated costs of doing the key research into sinking seaweed as an mCDR pathway. The framework was intended to detail and guide the needed scientific work to generate an empirical evidence base to evaluate the efficacy and impacts of sinking seaweed as an mCDR strategy. Without that fundamental base of evidence, opinions about the additionality, durability, and impacts of sinking seaweed are largely speculative.   

In all our work with Running Tide, their team showed a high commitment to doing the needed science. In fact, Running Tide’s track record on designing, conducting, and paying for the needed scientific research has set a high standard in this emerging field. It is simply not accurate to suggest that they did not make good faith efforts to do the needed science to support their activities.  

Ocean Visions View on the Role of Startups in Advancing RD&D

First principle: We urgently need to test all possible mCDR approaches to determine our options.  

In a perfect world, governments would have had the foresight and willingness to invest in the needed RD&D decades ago so that we would already have answers to all the fundamental questions about the efficacy and impacts of various mCDR approaches. Yet, as with many aspects of combatting climate change, collective delay and inaction have left us in a difficult spot. Time is short to get answers to the critical questions that need to be answered this decade for all mCDR pathways in order to make well-informed decisions about which, if any, can scale in 2030 and beyond. 

The good news is that the past few years have seen a significant increase in interest and investment in CDR RD&D in public, philanthropic, and private sectors. Importantly, recent funding from public and philanthropic sources show the potential and power of the private sector to contribute to the mCDR RD&D environment.  

MCDR is certainly not the first field in which the private sector has played a critical role in advancing RD&D. Drug and vaccine development, computer science (including artificial intelligence), and telecommunications are all fields where the private sector has led research and development of innovative technologies that have become central to human wellbeing. 

Our experience working with mCDR startups is that the founders and staffs are driven by a deep motivation to contribute to finding solutions to the dangerous future we are facing. They are trying their best to do robust science while balancing precaution and urgency and staying financially solvent – without which none of the RD&D would happen. A good portion of the revenue generated through sales of carbon credits is invested into solving science and engineering challenges. We have come to know individuals in many of these startups and they are predominantly smart, talented, and motivated. They are eager for science advice, to engage with the larger RD&D community, and welcoming of all feedback. They deserve an assumption of positive intent. 

While the closure of Running Tide is a setback for mCDR and for the nascent mCDR industry, it is not the end of mCDR. MCDR encompasses a diverse set of approaches, and companies have different business models to test these approaches – including working in different geographies as well as forging different types of corporate and research partnerships. Each of these startups needs to be judged on their own merit even though some of the challenges are similar.   

Should one or more mCDR approaches prove to be sufficiently effective and safe to warrant scaling, we will still have to answer the question of who will scale these technologies, because it is only with scale that we get to climate benefit. Unless national governments decide to run CDR operations, private companies will be the most likely means to achieve scale.  

Meanwhile, for a startup to do the needed science and engineering to answer the questions and solve the challenges that stand in the way of scale, they have to get revenue, whether through government subsidy or through markets (or both). Growing a business while undertaking significant RD&D is a tall order, one that is faced by all novel forms of CDR, and a special challenge for mCDR due to the myriad difficulties of working in the ocean.   

Given the urgency of finding scalable, durable solutions, and ruling out false solutions as quickly as possible, Ocean Visions will continue to support start-ups in the space who are committed to doing rigorous and transparent science to advance humanity’s collective knowledge. The stakes are too high to do anything else. 

Brad Ack, CEO
David Koweek, Chief Scientist
Nikhil Neelakantan, Launchpad Director