The Rise and Fall of Running Tide: A Cautionary Tale in Marine Carbon Removal

Introduction

This article explores the trajectory of Running Tide, a carbon-removal startup founded by Marty Odlin in 2017, whose ambitious marine carbon-sequestration initiatives collapsed amid scientific, regulatory, and financial challenges. Through interviews with 40+ sources—including scientists, investors, and former employees—and analysis of corporate filings, internal documents, and shipping data, we trace the company’s ascent, its flawed operational model, and the lasting implications for the emerging marine carbon-removal industry.

The Rise: A Vision of Oceanic Carbon Capture

In 2022, Running Tide emerged as a darling of Silicon Valley’s carbon-removal funding boom, securing $54 million in Series B funding led by Lowercarbon Capital. The startup’s core thesis: deploy free-floating “micro-forests” of seaweed on biodegradable buoys to sequester atmospheric carbon via oceanic uptake and deep-sea burial, targeting gigatons of CO₂ removal.

Led by Odlin, a former groundfishing fleet operator’s son, Running Tide pivoted from oyster aquaculture to carbon removal, initially pitching seaweed-sinking buoys as a scalable solution. By 2022, the company expanded operations to Iceland, a country lauded for its marine expertise, to pilot large-scale experiments. With the tech giant Microsoft as a target client, Running Tide claimed its kelp-seeded buoys would sequester carbon for 800+ years, positioning itself as a leader in “nature-based” carbon removal.

The Flaws: Unverified Science and Regulatory Shortcuts

Preliminary Failures in Maine

Running Tide’s initial experiments in Maine (2021–2022) revealed critical flaws. Cotton lines used to seed kelp spores proved chemically unstable in seawater, with buoys and moorings washing ashore at Cape Cod, triggering regulatory scrutiny from the Massachusetts Division of Marine Fisheries. Internal data suggested kelp growth was an order of magnitude below projections (10 tons vs. 10,000 tons annually), prompting concerns about data manipulation to secure investor confidence.

Shift to Wood Chips: A High-Risk Gambit

Facing pressure to scale, Running Tide abruptly abandoned seaweed buoys in favor of dumping 25,000 tons of chemically treated Canadian wood chips off Iceland’s coast. This pivot—from marine vegetation to wood-chip sequestration—ignored scientific consensus: marine carbon-removal experts criticized the technique as “poorly validated,” with James Kerry (OceanCare) noting alkaline dust treatment (for ocean alkalinity enhancement) and wood-chip sinking as mutually exclusive processes, as the alkaline reaction requires surface exposure, while sinking occurs at depth.

Regulatory Ambiguity in Iceland

Iceland’s environmental agencies flagged Running Tide’s 2022 research permit application as “inadequate,” citing unquantified carbon-removal potential and unassessed ecosystem impacts. Despite objections from scientists like Hrönn Egilsdóttir (Marine and Freshwater Research Institute), the Ministry of Environment granted approval, classifying the project as “research” rather than “dumping.” This regulatory ambiguity enabled Running Tide to proceed without independent verification, though its wood-chip deployment violated the EEZs (Exclusive Economic Zones) of Denmark, the Faroe Islands, and Canada, according to ship-tracking data.

The Collapse: Financial and Scientific Reckoning

By 2024, Running Tide’s operational momentum waned. After failing to secure Microsoft’s long-term contract and facing mounting costs ($18,000/day for barge rentals), the startup ceased operations, leaving 100+ workers unemployed and 25,000 tons of uncertified carbon credits in its wake.

Technical and Ecological Failures

Independent scientists confirmed that Running Tide’s wood-chip dumping had minimal or no net carbon sequestration. Jón Ólafsson (University of Iceland) noted that the North Atlantic region’s carbon flux is limited to 6 months annually, making sustained sequestration impossible. Ecologists like Samantha Joye (University of Georgia) warned of “dead zones,” as wood-chip decomposition depletes oxygen in marine sediments, harming benthic ecosystems critical for drug discovery and climate research.

Broader Industry Implications

The demise of Running Tide underscores systemic risks in the unregulated voluntary carbon market, where companies like Microsoft purchased 2.8 million tons of unverified credits (only 42,000 third-party verified) in 2023. The marine carbon-removal sector now faces scrutiny:

• Sector Consolidation: Giants like Microsoft and Shopify continue investing in experimental projects, with Ebb Carbon securing $24.75 million for ocean alkalinity enhancement.

• Scientific Gaps: Marine sedimentation rates (1 mm/1,000 years) and ecosystem resilience are poorly understood, raising questions about large-scale deployment.

• Market Incentives: Stacy Kauk (Isometric) criticizes the “lipstick on a pig” phenomenon, noting voluntary credits prioritize corporate greenwashing over real carbon reduction.

Conclusion

Running Tide’s collapse exposes the fragility of relying on unproven marine carbon-removal technologies. While the startup claimed to “fix the Godzilla of climate change,” its legacy is a cautionary tale: without rigorous scientific validation, regulatory accountability, and transparent third-party oversight, ocean-based carbon solutions risk exacerbating ecological harm. As the industry races to scale, the lessons of Running Tide’s failure are clear: climate action must be grounded in peer-reviewed science, not speculative theories.

Updated 12-17-2025: Woods Hole Oceanographic Institute’s involvement in Running Tide’s advisory board was clarified, with a member participating in an independent evaluation team, not the scientific advisory board.