Ocean-Based Carbon Sequestration

Detailed overview of innovation with sample startups and prominent university research

What it is

Ocean-based carbon sequestration encompasses various methods that enhance the ocean’s natural ability to absorb and store atmospheric carbon dioxide (CO2). These strategies aim to leverage the ocean’s vast capacity as a carbon sink to mitigate climate change.

Impact on climate action

Ocean-Based Carbon Sequestration aims to mitigate climate change by utilizing ocean ecosystems to absorb and store carbon dioxide. This innovative approach enhances carbon sinks, reducing atmospheric CO2 levels and buffering against ocean acidification, thus fostering marine biodiversity and supporting sustainable development goals.


  • Biological Pump: The ocean’s natural biological processes, involving phytoplankton absorbing CO2 through photosynthesis, transfer carbon to deeper layers as organisms die and sink.
  • Ocean Alkalinity Enhancement: Increasing the ocean’s alkalinity, for example by adding minerals, can enhance its capacity to absorb and store CO2.
  • Artificial Upwelling and Downwelling: Controlled manipulation of ocean currents can bring nutrient-rich deep waters to the surface, stimulating phytoplankton growth and CO2 uptake, or transport surface waters with higher CO2 concentrations to the deep ocean for storage.
  • Seaweed Cultivation: Cultivating seaweed on a large scale can sequester carbon through photosynthesis, and the harvested seaweed can be used for various applications, including biofuels, bioplastics, and food.
  • Ocean Fertilization: Introducing nutrients, such as iron, to specific ocean regions can stimulate phytoplankton growth and CO2 absorption.

TRL : Varies significantly depending on the specific method, ranging from 3-4 for emerging technologies like artificial upwelling to 6-7 for seaweed cultivation.

Prominent Innovation themes

  • Autonomous Ocean Vehicles for Carbon Monitoring: Startups are developing fleets of autonomous underwater vehicles (AUVs) and surface vehicles (ASVs) equipped with sensors to monitor CO2 levels, ocean currents, and biological activity, providing crucial data for optimizing carbon sequestration strategies.
  • Precision Ocean Fertilization Techniques: Researchers are exploring innovative techniques for targeted nutrient delivery to specific ocean regions, minimizing potential ecological impacts and maximizing CO2 uptake by phytoplankton.
  • Integrated Seaweed Farming Systems: Companies are developing integrated systems for seaweed cultivation that incorporate advanced monitoring, harvesting, and processing technologies, enhancing the efficiency and scalability of seaweed-based carbon sequestration.
  • Carbon-Negative Biochar from Seaweed: Startups are exploring methods for converting seaweed biomass into biochar, a stable form of carbon that can be sequestered in the ocean floor for long-term carbon removal.
  • Electrochemical Ocean Alkalinity Enhancement: Researchers are investigating the use of renewable energy-powered electrochemical processes to increase ocean alkalinity, enhancing CO2 absorption and storage.

Other Innovation Subthemes

  • Biological Pump Utilization
  • Ocean Alkalinity Enhancement Methods
  • Controlled Ocean Current Manipulation
  • Large-Scale Seaweed Cultivation
  • Nutrient-Induced Ocean Fertilization
  • Autonomous Carbon Monitoring Vehicles
  • Precision Nutrient Delivery Systems
  • Integrated Seaweed Farming Technologies
  • Seaweed Biomass Biochar Production
  • Electrochemical Alkalinity Enhancement
  • Ocean Carbon Storage Capacity Assessment
  • Phytoplankton Growth Optimization
  • Deep Ocean Carbon Storage Techniques
  • Oceanic Carbon Sink Expansion
  • Marine Carbon Sequestration Economics
  • Ecological Impact Mitigation Strategies
  • Remote Sensing for Ocean Carbon Sequestration
  • Carbon-Negative Seaweed Products
  • Renewable Energy-Powered Ocean Processes

Sample Global Startups and Companies

  • Running Tide:
    • Technology Focus: Running Tide focuses on ocean-based carbon sequestration using innovative methods such as ocean afforestation. They deploy biodegradable structures to grow kelp forests, which absorb CO2 from the atmosphere and store it in the ocean.
    • Uniqueness: Their approach is distinctive for using natural ecosystems like kelp forests to sequester carbon effectively. They combine ecological restoration with carbon offsetting, offering a scalable and sustainable solution.
    • End-User Segments: Running Tide’s solutions appeal to companies and individuals seeking effective carbon offsetting strategies, particularly in sectors like maritime transport, aviation, and corporate sustainability programs.
  • Ocean-Based Climate Solutions, Inc.:
    • Technology Focus: This company likely focuses on various technologies related to ocean-based carbon sequestration, potentially including direct air capture and storage beneath the ocean floor or in deep-sea formations.
    • Uniqueness: They may stand out for their advanced engineering solutions designed to capture and store carbon in oceanic environments, offering scalable and potentially long-term carbon storage solutions.
    • End-User Segments: Their technologies could cater to industries seeking large-scale carbon sequestration options, such as energy producers, heavy industry, and governments aiming to meet ambitious carbon neutrality targets.
  • Kelp Blue:
    • Technology Focus: Kelp Blue specializes in large-scale kelp farming for carbon sequestration and sustainable food production. They harness the rapid growth rate of kelp to absorb CO2 from the atmosphere and provide a renewable biomass resource.
    • Uniqueness: Their focus on integrated solutions for carbon sequestration and sustainable aquaculture sets them apart. They emphasize the dual benefits of carbon capture and the production of valuable kelp-based products.
    • End-User Segments: Kelp Blue’s solutions target industries interested in sustainable agriculture, aquaculture, and renewable energy, offering scalable alternatives to traditional carbon offsetting methods.

Sample Research At Top-Tier Universities

  • Woods Hole Oceanographic Institution (WHOI):
    • Technology Enhancements: WHOI researchers are pioneering advancements in ocean-based carbon sequestration by exploring natural and engineered methods to enhance carbon uptake in ocean ecosystems. They are investigating methods such as ocean fertilization and alkalinity enhancement to promote the absorption and storage of CO2.
    • Uniqueness of Research: WHOI’s approach includes field experiments and modeling studies to assess the effectiveness and environmental impacts of various carbon sequestration techniques. Their research emphasizes the importance of understanding ocean dynamics and biogeochemical processes to optimize carbon removal strategies.
    • End-use Applications: The research at WHOI has implications for mitigating climate change by potentially offsetting CO2 emissions from industrial sources. If successful, these methods could contribute to global efforts to achieve carbon neutrality and stabilize atmospheric CO2 concentrations.
  • Scripps Institution of Oceanography:
    • Technology Enhancements: Scripps researchers are developing innovative technologies for ocean-based carbon sequestration, such as artificial upwelling systems and enhanced weathering of minerals in seawater. These technologies aim to enhance the natural processes of carbon uptake and storage in the ocean.
    • Uniqueness of Research: Scripps’ research integrates oceanography, climate science, and engineering to explore scalable and sustainable solutions for carbon sequestration. They are exploring new materials and methods to increase the efficiency and permanence of carbon removal from the atmosphere.
    • End-use Applications: The technologies developed at Scripps could potentially be applied globally to mitigate climate change impacts by reducing CO2 levels in the atmosphere. They could also contribute to restoring ocean health and biodiversity by addressing ocean acidification and enhancing nutrient availability for marine ecosystems.
  • University of Washington:
    • Technology Enhancements: Researchers at the University of Washington are investigating novel approaches to ocean-based carbon sequestration, such as biochar sequestration in marine sediments and enhanced weathering of minerals on coastal ecosystems. These methods aim to enhance carbon storage capacity and ecosystem resilience to climate change.
    • Uniqueness of Research: UW’s research emphasizes interdisciplinary collaboration between marine science, geoengineering, and policy analysis to develop ethical and effective strategies for ocean-based carbon sequestration. They are evaluating the environmental, economic, and social implications of different carbon removal techniques.
    • End-use Applications: The research outcomes from UW could inform policy decisions and international agreements on climate change mitigation strategies. They could also lead to the development of new industries and technologies focused on carbon removal and ocean ecosystem restoration.

commercial_img Commercial Implementation

While the commercial implementation of some ocean-based carbon sequestration methods is still in its early stages, seaweed cultivation for various applications, including carbon removal, is gaining traction. Companies like Running Tide and Kelp Blue are already selling carbon credits based on their seaweed farming activities.