In Halifax, Nova Scotia, a burgeoning industry is working to combat global warming by harnessing the oceans’ absorbent capabilities. Numerous companies and academic organizations are exploring the idea of using various materials like rocks, nutrients, crop waste, or seaweed to sequester carbon dioxide in the ocean for extended periods of time. Over the past four years, almost 50 field trials have been conducted, with startups securing significant early-stage funding. However, there are ongoing debates within the field regarding the potential impacts of large-scale deployment on the oceans and the actual climate benefits. Critics caution that these efforts may be advancing too rapidly without adequate safeguards in place.
According to a report by The Associated Press, here are key points about companies aiming to leverage the oceans to capture carbon:
– The Challenge: Despite efforts to reduce emissions, most climate models indicate that additional measures are needed to address global warming by removing heat-trapping gases.
– Ocean Potential: The vast surface area of the ocean offers a promising avenue for mitigating climate change, as it naturally absorbs heat and carbon.
– Scientific Approach: Many companies are exploring ways to either reduce or transform carbon dioxide in the ocean to prevent it from interacting with the atmosphere. Methods include using substances like magnesium oxide to convert carbon dioxide into stable compounds or cultivating seaweed and algae to absorb carbon.
– Financing: Ocean startups are selling carbon credits, representing the removal of one metric ton of carbon dioxide from the air, to fund their initiatives. However, the industry’s carbon removal capacity is currently insufficient to meet long-term climate goals.
– Community Considerations: Coastal communities have shown varying levels of support for these projects, with some expressing concerns about potential impacts on local ecosystems and industries.
Overall, while there is growing interest and investment in ocean-based carbon capture solutions, there are significant challenges and uncertainties that must be addressed to ensure the effectiveness and sustainability of these initiatives.
Sara Nawaz, the research director at the Institute for Responsible Carbon Removal at American University, acknowledged the challenges scientists face in engaging with communities and gaining their support. Initial studies indicate public reluctance towards the concept of “engineering” the climate. What other obstacles are in the way?
Working in the ocean presents a constantly changing and complex environment for researchers. New discoveries are still being made about how the ocean absorbs and cycles carbon, while any substances introduced into seawater are at risk of sinking, dispersing, or being carried away to other areas, making it difficult to monitor the ocean’s responses.
“We cannot monitor every location at all times,” remarked Katja Fennel, head of the oceanography department at Dalhousie University. She is involved in assessing the amount of carbon captured by Planetary’s project in Halifax Harbour through modeling efforts.
Questions remain regarding the longevity of carbon capture methods. This is particularly pertinent for companies utilizing organic materials like algae or wood chips, as the decomposition of these materials could potentially release carbon dioxide back into the atmosphere depending on where it occurs.
Even if these solutions prove effective in the long run, most companies currently lack the scale needed to significantly impact the climate. Achieving the current climate targets will demand substantial resources, energy, and financial investments.
David Ho, the co-founder and chief science officer of the nonprofit (C)Worthy, highlighted the challenge of scaling up operations to handle billions of tons of carbon annually. Planetary’s Burt envisions a future where minerals are extracted from power plants and water treatment facilities along coastlines worldwide, necessitating a consistent supply of minerals like magnesium oxide and the energy for extraction and transportation.
The growth of seaweed and algae would need to increase dramatically. The National Academies of Sciences, Engineering, and Medicine estimated that encircling nearly two-thirds of the world’s coastlines with kelp would be required to make a meaningful impact on global warming. Companies like Seafields, testing in the Caribbean, envision vast Sargassum farms between Brazil and West Africa spanning over 200 miles wide.
Expanding these operations comes with the risk of unintentional environmental harm that may not have been evident in small-scale trials and could have far-reaching consequences due to global water circulation.
Despite these challenges, David Ho emphasized the necessity of exploring carbon removal strategies as an alternative to the dire implications of unchecked climate change.
This article was made possible with support from the Walton Family Foundation. The AP is responsible for the content.
For more information, contact the AP’s global investigative team at Investigative@ap.org or visit https://www.ap.org/tips/.
