As the urgency to address climate change intensifies, innovative solutions for carbon dioxide removal (CDR) are gaining traction. Among the emerging approaches, Ocean CDR methods are garnering significant attention due to the ocean's pivotal role in regulating the Earth's carbon cycle and its vast potential for scalability. 

Oceans cover over 70% of the Earth's surface and play a crucial role in the global carbon cycle, absorbing and storing vast amounts of carbon dioxide (CO2) from the atmosphere. This natural process, known as the ocean carbon sink, has been a key factor in mitigating the impacts of anthropogenic CO2 emissions. However, as atmospheric CO2 levels continue to rise, the oceans' ability to absorb and store carbon is becoming increasingly strained. 

Ocean CDR methods aim to enhance the ocean's natural carbon sequestration capabilities, offering a promising avenue for large-scale carbon removal and long-term storage. By leveraging the vastness of the oceans and their natural carbon cycle, these methods have the potential to make a significant impact in mitigating the effects of rising atmospheric CO2 levels. To facilitate deployment of the novel ocean CDR methods at scale methodologies and protocols are needed to set the requirements for quantification of carbon removal and safety of the operations. 

A Look at Ocean CDR Methodologies 

Several Ocean CDR methods are currently being explored and developed in the CDR community, each with its unique approach and potential: 

Ocean Storage of Biomass (OSB): This emerging method involves using photosynthesis as the CO2 capture step, then storing the captured CO2 in a stabilized form in the ocean, primarily in anoxic basins but also considering deep-sea basins with suitable conditions. 

Electrochemical Methods: These techniques use electrochemical reactor-based processes to permanently sequester CO2 in the ocean as bicarbonates and solid mineral carbonates. 

Ocean Alkalinity Enhancement: This method involves increasing the alkalinity of seawater by additives in the open ocean, enhancing its ability to absorb and store CO2 from the atmosphere. 

Blue Carbon: This method focuses on the conservation and restoration of coastal ecosystems, such as mangrove forests and seagrass meadows, which are highly efficient at sequestering and storing carbon. 

Ocean Fertilization: This approach involves adding nutrients to the ocean to stimulate phytoplankton growth, which can then absorb CO2 from the atmosphere through photosynthesis. While promising, concerns exist about potential negative ecological impacts. 

As the potential of Ocean CDR methods becomes more apparent, investment in the sector is on the rise. In 2023, Ocean CDR companies attracted over $200 million in funding, with major investors including Lowercarbon Capital, Counteract, Carbon Removal Partners, and the U.S. Department of Energy. 

This influx of capital is fueling research and development efforts, as well as pilot projects and early-stage deployments to advance Ocean CDR technologies toward commercial viability and scalability. 

Puro is Helping to Pave the Way for Ocean CDR 

Ocean Storage of Biomass (OSB) is a particularly intriguing Ocean CDR method due to its potential for scalability, possibility to utilize existing infrastructure, and long-term carbon storage. By depositing carbon-rich biomass in suitable seafloor environments, organic matter can be preserved for hundreds or thousands of years, effectively removing CO2 from the atmosphere for a meaningful period to counteract climate change. 

While OSB holds significant promise, there is a need to standardize the way the early projects monitor and report their climate impact. As a leader in the carbon removal space, Puro is actively working to fill the need for standardized methodologies in collaboration with dedicated parties. Our goal is to develop a comprehensive methodology for OSB this year, ensuring that this approach is thoroughly understood and can be implemented effectively and responsibly. Puro's ongoing efforts to develop a robust methodology for OSB reflects our commitment to exploring innovative solutions and advancing the field of carbon removal. 

The electrochemical ocean CDR (EO-CDR) is also intriguing. Among the many ocean sequestration pathways, EO-CDR is happening in a closed reactor which makes it easier to measure and report the required parameters. Puro's ongoing focus is to develop a robust methodology for electrochemical sequestration together with the early developers. 

And, as a proud partner of the 2024 Advancing Ocean CDR Summit happening July 10-11 in Boston, Massachusetts, USA, Puro is leading the way for collaboration, investment, and research in Ocean CDR, which is certain to play a vital role in achieving global climate goals.