Plan Sea: Ocean Interventions to Address Climate C

In this episode of Plan Sea, hosts Anna Madlener and Wil Burns sit down with Dr. Phil Renforth and Dr. Mijndert Van der Spek of Heriot-Watt University to unpack their newly published, harmonized framework for evaluating the viability of ocean alkalinity enhancement (OAE) pathways. Moving beyond lab-scale assumptions, their approach integrates techno-economic analysis (TEA) and lifecycle assessment  (LCA) to allow the exploration of 54 known OAE variations and how they perform under future, decarbonized energy scenarios. The conversation highlights why real-world data, a cleaner energy grid, and feasibility assessments are important for determining which OAE pathways will deliver results in global scale carbon removal.  With any emerging solution, both feasibility and cost must be effectively evaluated. Renforth and Van der Spek combine two essential lenses – techno-economic analysis (TEA) and lifecycle assessment (LCA) – to build a comprehensive picture of OAE’s real potential. TEA determines if a pathway is economically viable and scalable, while LCA screens for its full environmental impacts, not only if it is net-negative, but also whether it engages in “burden shifting,” or solving one problem while creating another. Operating far beyond “carbon balancing,” LCA works across a range of categories, from greenhouse gas emissions to terrestrial and marine acidification, resource use, and pollution. Together, the two tools are meant to provide a level of quantification for decision-makers investigating the viability of any CDR approach.  In looking at the framework, Dr. Renforth and Dr. Van der Spek began by introducing  the framework’s structure through a case study of BPMD and its functionality as OAE technology. Rather than offering predictions, the framework helps to show how different technologies perform under current assumptions. This means the framework should not be viewed as forecasting long-term outcomes on its own, but instead as a tool to see how each pathway changes.  While these tools are powerful, they are incomplete and alongside rigorous research into the broader social, regulatory, and ethical implications of each potential pathway. For example, LCA aims to measure global stressors by normalizing impacts, but it does not have the ability to detect localized effects. This highlights that any comparison drawn from the framework must be paired with site-specific environmental assessments. Together, these layers of analysis provide a more realistic understanding of where OAE pathways may be within reach.  Join us as we dive deeper into this framework and how it aims to spur further evaluation and innovation in OAE by listening to the episode above! Subscribe on your preferred podcast platform and find the entire series here.  ACRONYMS / CONCEPTS: CDR: Carbon Dioxide Removal OAE: ocean alkalinity enhancement  TEA: Techno-Economic Analysis LCA: Lifecycle Assessment BPMED: Bipolar Membrane Electrodialysis Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this episode of Plan Sea, hosts Anna Madlener and Wil Burns dive deep into the new Biogeosciences special issue focused on the environmental safety of ocean alkalinity enhancement (OAE). This episode’s guests are Dr.Lydia Kapsenberg and Dr. Tyler Cyronak who helped edit the special issue. Compiling more than 20 studies, the special issue serves as a “one-stop shop” of the latest peer-reviewed science on the environmental safety of OAE — ranging from responses of micro algae and corals, to the influence of biogeochemical cycling and trace metals. Tune in as we unpack what insights these studies collectively suggest and discuss what it means for next steps in environmental safety research for OAE.  The volume of OAE research has grown dramatically in recent years — increasing four-fold over the last five years. The Biogeosciences special issue shines a light on this rapidly evolving landscape and offers a tool for researchers, funders, regulators, and other partners to access centralized information on potential ecological risks, environmental monitoring standards, and feedstock safety related to multiple OAE approaches.  Throughout the discussion, many themes arise, including the question: How important is it to understand both system-wide patterns and local ecological realities? Lydia and Tyler highlight that while the Biogeosciences studies suggest that many phytoplankton species appear to be resilient under expected OAE conditions, local species and ecological contexts must still be factored into any field research design. This is where researchers have an important responsibility to meaningfully engage with communities on what matters most for their local marine ecosystems and align planned environmental monitoring efforts accordingly. For researchers, policymakers, and communities assessing OAE’s environmental safety as a potential climate solution, the Biogeosciences special issue offers a crucial early evidence base and a clearer picture of what questions come next. As mentioned during the episode, Carbon to Sea’s Environmental Impact Monitoring Framework is now available for public review and comment here, through December 12th. Carbon to Sea and the Prince Albert II of Monaco Foundation are also currently soliciting proposals for scientific research on the safety of OAE on commercially and culturally valued marine species. You can view the full funding opportunity and submit a proposal by January 16, 2026. Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative and the American University Institute for Responsible Carbon Removal. ACRONYMS / CONCEPTS: CDR: Carbon Dioxide Removal EPA: Environmental Protection Agency  MRV: monitoring, reporting, and verification OAE: ocean alkalinity enhancement OAEPIIP: Ocean Alkalinity Enhancement Pelagic Impact Intercomparison Project Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, hosts Anna Madlener and Wil Burns kick off season three of the podcast with Woods Hole Oceanographic Institution (WHOI) researchers Dr. Adam Subhas and Jennie Rheuban to discuss the LOC-NESS project — a small-scale, open-ocean research trial on ocean alkalinity enhancement (OAE). The project’s co-principal investigators join Anna and Wil to recount the process of receiving a first-of-its-kind permit from the U.S. Environmental Protection Agency (EPA), the role of local community engagement, and the project’s early findings.  A few weeks ago, WHOI completed its highly controlled research trial in the Gulf of Maine to study the environmental safety and efficacy of OAE as a carbon dioxide removal technique. Approved by the EPA after a two-year, rigorous permitting process, the LOC-NESS project introduced small amounts of purified sodium hydroxide – a compound often used to balance the pH of drinking water – to the ocean surface waters, along with a harmless red dye to help track it. This field study came after years of preparation and development, including extensive laboratory experiments, ocean modeling, and a growing body of scientific literature.  Dr. Adam Subhas is an Associate Scientist at WHOI and the project lead for LOC-NESS. Adam credits the project’s success so far to the comprehensive preparation and collaboration between WHOI scientists and EPA staff — on everything from ocean modeling and biogeochemical impact evaluation, to engaging communities and local industries on what to expect from the research. He also talks about how their pursuit of the first-ever ocean carbon dioxide removal (oCDR) permit under the Marine Protection, Research, and Sanctuaries Act of 1972, helped the LOC-NESS team refine their procedures, improve their approach, and make the project more responsive to feedback from their community. Jennie Rheuban is a WHOI Research Specialist and serves as a co-principal investigator for LOC-NESS. Jennie points to community engagement as a critical component of LOC-NESS’s development, recounting the project’s years-long effort to engage with questions from a range of stakeholders, including the fishing community. By emphasizing its position as an independent scientific research project without commercial ambitions, WHOI was able to cultivate credibility and gather important community inputs that shaped the scope and methodologies of the research. For example, the team spent additional time researching types of fish larvae in potential field trial regions to bring that information back to the local fisherman. Looking ahead, LOC-NESS researchers will continue to analyze data gathered during this summer’s trial to understand the impacts and efficacy of the alkalinity dispersal.  More information about LOC-NESS’s findings will be shared at the Ocean Sciences Meeting in February 2026. Plan Sea is a semi-weekly podcast exploring ocean-based solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.  Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, host Anna Madlener is joined by Na’im Merchant, host of The Carbon Curve podcast and Executive Director of Carbon Removal Canada, for a special co-hosted episode of the two podcasts. Recorded live at the Carbon to Sea 2025 Annual Convening, Anna and Na’im speak with Lennart Bach, Associate Professor and ocean alkalinity enhancement (OAE) scientist at the University of Tasmania, to share insights and key takeaways from this year’s convening. Last month, Carbon to Sea hosted its third Annual Convening in Washington, D.C., bringing together scientists, entrepreneurs, and policymakers to share recent progress and discuss a path forward for OAE. Bach, who previously spoke with Plan Sea on his work in ocean iron fertilization, was a speaker on this year’s “Scientific Research Progress and Updates” panel. Focused on the environmental impacts of OAE, Bach’s research aims to learn more about how OAE approaches may impact the marine ecosystem. Building on conversations from the convening, Bach joins Anna and Na’im to share his optimism about the future of OAE, while also recognizing the potential challenges posed by a dip in the “hype cycle” that emerging scientific fields often face. However, Bach said he feels confident in progress that’s already been made and noted the importance of building on preliminary findings about OAE’s potential to conduct more targeted research.  Na’im similarly addresses this challenging moment for the climate industry writ large, as it faces reduced funding and policy support in many areas, with new geopolitical headwinds. Drawing on his experience working across the carbon removal space, Na’im offers advice for how the OAE field can address this moment by prioritizing focused research, establishing an updated roadmap, and exploring new funding pathways.  Looking ahead, both Na’im and Bach highlight the importance of aligning on MRV approaches, cross-sector partnerships, increased community and policymaker engagement, and exploring new funding pathways in order to advance OAE research. As this year’s convening exemplified, the immediate opportunities in OAE research have largely been addressed; what lies ahead is more complex and demands significantly greater coordination. Listen to our previous episode with Lennart Bach here. ACRONYMS / CONCEPTS:  OAE (2:28) MRV (18:06) DAC (23:37) CRCF (29:59) ETS (29:59) ERW (36:16) Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

This episode of Plan Sea was recorded live at the Ocean Visions Biennial Summit 2025, and features conversations with experts from Ocean Visions, UArctic, and WHOI to discuss their work in the ocean-climate nexus. Host Anna Madlener is joined again by special co-host, Danny Gawlowski, Carbon to Sea’s Senior Manager of Communications and Policy. Listen to Part One of Plan Sea’s coverage of the Ocean Vision Biennial here. Guests on this episode include:  Nikhil Neelakantan, Senior Program Officer at Ocean Visions Marianne Hagen, Co-lead of Seabed Curtain Project at UArctic Frozen Arctic Conservation Network Kilaparti (Rama) Ramakrishna, Director of Marine Policy Center and Senior Advisor to the President on Ocean and Climate Policy at Woods Hole Oceanographic Institution David Koweek, Chief Scientist at Ocean Visions Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

This episode of Plan Sea was recorded live at the Ocean Visions Biennial Summit 2025, and features conversation with Ocean Visions CEO Brad Ack and other attendees to discuss their work in ocean-based carbon dioxide removal (oCDR). Host Anna Madlener is joined by a special co-host, Danny Gawlowski, Carbon to Sea’s Senior Manager of Communications and Policy. Guests on this episode include:  Brad Ack, CEO of Ocean Visions Marc von Keitz, Director at The Grantham Foundation for the Protection of the Environment Mariam Swaleh, Assistant Registrar of Research and Grants at Technical University of Mombasa, Team Lead at Ocean-Climate Innovation Hub Kenya, and OCI Fellow at the Global Ecosystem of Ocean Solutions Lily Schacht, Senior Carbon Removal Verification Engineer at 350Solutions Meg Chadsey, Carbon Specialist at Washington Sea Grant Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, hosts Anna Madlener and Wil Burns are joined by Drs. Sara Seck and Neil Craik to discuss the current governance and public funding landscape for ocean-based carbon dioxide removal (oCDR) research and innovation in Canada. They focus particularly on jurisdictional challenges in Nova Scotia, related to an increase in oCDR R&D in the province over recent years, and discuss broadly how to strengthen future policymaker and public engagement. Sara Seck is a Professor of Law at Dalhousie University’s Schulich School of Law, serving as the Yogis and Keddy Chair in Human Rights Law and the Director of the Marine & Environmental Law Institute. Dr. Seck sheds light on the complex and overlapping jurisdiction of land and ocean rights in Canada. She shares insights for oCDR stakeholders seeking to navigate this landscape to address permitting and other governance issues in coordination with the federal Canadian government, provincial governments, and First Nations leadership.  Neil Craik is a Professor at the University of Waterloo, with appointments to the Basillie School of International Affairs (BSIA) and the School of Environment, Enterprise, and Development. He is also a Senior Fellow at the Centre for International Governance Innovation and Co-Lead of the Environment and Resources Research Cluster at the BSIA. Dr. Craik discusses legislation and public funding opportunities that can help support oCDR initiatives in Canada. He also explains current procurement strategies for carbon credits across both the public and private sectors, and how oCDR can work towards compliance to access this market in the future.  During the episode, the Plan Sea guests and hosts consider the implications of good governance and policy on advancing the development and funding of oCDR initiatives. The oCDR field is reaching a pivotal moment, with many research projects now moving towards real-world field trials that will answer key scientific questions but also raise new challenges for navigating existing and emerging legislation. Doubling-down on public engagement and unlocking new funding opportunities will be increasingly important for advancing oCDR activities in Canada and elsewhere. ACRONYMS / CONCEPTS: CDR: Carbon Dioxide Removal  mCDR: Marine Carbon Dioxide Removal  MRV: Measurement, Reporting, and Verification  BBNJ Agreement: Agreement on Marine Biodiversity of Areas beyond National Jurisdiction TCA: Transforming Climate Action Research Program Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this episode of Plan Sea, hosts Anna Madlener and Wil Burns are joined by several guests to discuss new initiatives to improve data management and transparency in the carbon dioxide removal (CDR) industry. Jacki Long is an ocean scientist and co-founder of Submarine Scientific, a scientific consulting company focused on ocean modeling, expert verification support, and system wide strategy development for ocean-based carbon dioxide removal (oCDR). Jacki joins the Plan Sea hosts to discuss Submarine’s work pioneering a new initiative to standardize emerging data from ocean alkalinity enhancement (OAE) field trials. In collaboration with Carbon to Sea and the National Ocean Atmospheric Administration (NOAA), Submarine’s data protocol is undergoing an open comment period through March 7th, allowing researchers, partners, and community members to submit feedback.  Brad Rochlin and Tannis Thorlakson join to discuss their work at Cascade Climate, a philanthropically-backed nonprofit working to accelerate natural climate interventions such as enhanced rock weathering (ERW). Brad and Tannis share insights from Cascade’s development of a data quarry method that could fill an important gap in existing carbon data quantification methods — and ultimately unlock greater scientific understanding of ERW. During the episode, the guests and hosts consider how these data standardization and sharing efforts — across the OAE and ERW fields — are laying the foundation for enhanced research efficiency and increasing public trust in CDR methods as potentially viable solutions to slow the impacts of climate change. The ongoing work from Submarine Scientific and Cascade Climate aim to help researchers share learnings in real time, improve collaboration, and support data transparency.  ACRONYMS / CONCEPTS: CDR - carbon dioxide removal ERW - enhanced rock weathering OAE - ocean alkalinity enhancement IP - intellectual property (29:38)  NOAA - National Oceanic and Atmospheric Administration (38:28) CDRXIV (pronounced “see-dee archive”) (38:46) Hourglass (Listen to a previous episode here) (38:53) R&D - research & development (43:43) Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

Hey listeners, we want to hear from you! What 2024 milestone in the world of carbon removal should we be celebrating? And what do you hope to see in the marine CDR field in 2025? Leave us a quick voice message at www.speakpipe.com/planseapodcast It only takes a few seconds, and you could be featured in our next episode.  Thanks, and happy new year!  Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

This new episode features two OAE researchers and their insights from conducting field research as well as a special request to you, our listeners! In this edition of Plan Sea, hosts Anna Madlener and Wil Burns are joined by two leading ocean alkalinity enhancement (OAE) researchers: Dr. Jaimie Palter from the University of Rhode Island’s School of Oceanography and Dr. Dariia Atamanchuk from Dalhousie University’s Department of Oceanography. Palter and Atamanchuk both lead field research sites studying OAE and are part of Carbon to Sea’s Field Research Steering Committee.  Palter and Atamanchuk discuss their work leading field research sites studying OAE in coastal lagoon and ocean harbor settings, respectively, and share initial findings. The Plan Sea hosts and this episode’s guests underscore the importance of field research guiding the recommendation for scientifically robust, yet affordable and actionable monitoring, reporting, and verification (MRV) processes, and encourage greater collaboration between projects and across the sector. Also: we would like to hear from you, our listeners, before our next episode! Let us know what 2024 milestone we should be celebrating or what you hope to see in 2025 by leaving us a voice message here that may be used in our next episode! Acronyms used throughout the episode:  NOAA NOPP –  National Oceanic and Atmospheric Administration’s National Oceanographic Partnership Program (1:47)  AGU - American Geophysical Union (2:00) MRV - Monitoring, Reporting, and Verification (13:25) pCO2 - Partial pressure of carbon dioxide (34:58) EPA - Environmental Protection Agency (56:27) Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, hosts Anna Madlener and Wil Burns are joined by Captura CEO Steve Oldham to discuss Direct Ocean Capture technology. Captura is a Pasadena, CA-based company that is exploring the use of renewable energy to remove carbon from the ocean as a low-cost, large-scale climate solution. Learn more about Captura’s DOC approach and propriety technology on their website here.  Listen to our previous episode with Banyu Carbon’s Co-Founder & CEO Alex Gagnonon here. Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, hosts Anna Madlener and Wil Burns are joined by returning guest Mike Kelland, CEO and co-founder of Planetary Technologies, as well as Dr. Will Burt, Planetary’s Chief Ocean Scientist. Planetary is an ocean alkalinity enhancement (OAE) startup based in Halifax, Canada. Link to Planetary's webinar on recent trial results here. Listen to our first episode with Mike Kelland here. ACRONYMS / CONCEPTS: NOAA (19:39): National Oceanographic and Atmospheric Association MRV (32:39): Monitoring, Reporting and Verification ROMS (34:35): Regional Ocean Modeling System EPA (53:06): Environmental Protection Agency London Convention and Protocol (53:41) Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In today's episode, hosts Anna Madlener and Wil Burns are joined by Grace Andrews from Hourglass Climate. They discuss Hourglass' work on environmental monitoring and carbon removal quantification of Ocean Alkalinity Enhancement (OAE)  trials as a research non-profit. Grace started her career in academic research, studying chemical weathering and alkalinity under glaciers and ice sheets. She later explored the relationship between rock weathering and ocean-based carbon removal, which prompted her shift to the private sector, at Vesta – a climate startup focused on coastal olivine-based alkalinity enhancement. Today, she’s the Executive Director of Hourglass Climate, where she leads a team focused on conducting transparent and open-source research on mineral-based OAE techniques. In this episode, the Plan Sea hosts and Grace discuss how Hourglass is advancing current OAE field trials, including quantifying the efficacy, assessing the safety of projects, and expanding strategies to effectively share information and communications. To view the Ocean Visions webinar referenced on the podcast, click here: LINK. Plan Sea is a semi-weekly podcast exploring ocean-based climate solutions, brought to you by the Carbon to Sea Initiative & the American University Institute for Responsible Carbon Removal.

In this edition of Plan Sea, hosts Anna Madlener and Wil Burns discuss a novel sunlight-driven approach to marine carbon dioxide removal (mCDR) with Alex Gagnon, co-founder and CEO of Banyu Carbon, a direct ocean removal startup based in Seattle, WA.

Hosts Anna Madlener and Wil Burns discuss the evolving landscape of marine carbon dioxide removal (mCDR) with Rory Jacobson, Acting Division Director for Carbon Dioxide Removal at the U.S. Department of Energy (DOE).

Plan Sea dives into the world of carbon removal certification, joined by experts Sophie Gill, Jing He, and Jennifer Yin from Isometric — a carbon credit certification platform and registry focused on high-quality carbon removal.

Carbon to Sea & the American University Institute for Responsible Carbon Removal announce a new collaboration for the second season of “Plan Sea” — a semi-weekly podcast exploring ocean-based climate solutions. Plan Sea will release episodes on a semi-weekly basis throughout Fall 2024, and is hosted by Wil Burns and Anna Madlener.

Our guests today, Lennart Bach, at the Institute for Marine and Antarctic Studies, University of Tasmania, and Veronica Tamsitt, Head of Oceanography at the mCDR MRV company, Submarine, are two of the authors of a very interesting research article recently published in the journal Global Biogeochemical Cycles, titled “Identifying the Most (Cost-)Efficient Regions for CO2 Removal With Iron Fertilization in the Southern Ocean.”  Ocean Iron Fertilization (OIF) is really the “OG” of marine-based CDR approaches, with the Ocean Iron Hypothesis being advanced by oceanographer John Martin in the 1980s, and 13 field experiments ensuing over the course of two decades, beginning in 1993, with the last experiment conducted in 2009.  It’s fair to say that interest in OIF largely fell into abeyance for a protracted period of time. However, recently, largely due to the efforts of researchers at Woods Hole, including Ken Buesseler, who we interviewed on a previous episode, as well as a spate of recent high-profile publications, OIF seems to be front and center again in the discussion of mCDR methods. In this episode we discuss some of the most pertinent issues to assessing the potential role of OIF in a marine CDR portfolio, including costs, risks, and legal considerations. We hope this interview can do justice to some of the article’s most important conclusions.

Our guest today is Freya Chay, Carbon Removal Program Lead at CarbonPlan, a non-profit organization in the US working on data and science for climate action by improving the transparency and scientific integrity of climate solutions with open data and tools.  Carbon Plan and Freya have produced a number of stellar publications and tools, widely regarded in the field and insightfully crafted. Notably, the CDR primer is a bibliography of crucial concepts to understand if one wants to enter the world of CDR. Similarly, the CDR Verification Framework is an insightful and informative tool to explore detailed layers of CDR approaches. In this episode, we discuss Freya's perspective on barriers to scaling, market responsibilities and market-shaping opportunities. We also discuss uncertainty and opportunities in Monitoring, Reporting and Verification. 

Welcome back to the Plan Sea Podcast as we kick off our final stretch of season 1.  Today's episode focuses on the findings and observations in a recently published paper in the Journal of Environmental Science and Policy entitled  Towards just, responsible, and socially viable carbon removal: lessons from offshore DACCS research for early-stage carbon removal projects We welcome the paper's coauthors Sara Nawaz, Director of Research at the Institute of Carbon Removal, Law and Policy, and Terre Satterfield, Professor of Culture, Risk and Environment at the Institute for Resources, Environment and Sustainability, University of British Columbia to the episode.