Take Care Before Enlisting the Oceans in the Climate Fight
To repair the damage weve inflicted on the planet, its generally agreed that as well as reducing how much carbon we emit in the future, carbon dioxide will need to be removed from the atmosphere and stored somewhere else, permanently. The ocean is a pretty attractive destination. Already the worlds largest carbon sink, the ocean contains 50 times more CO2 than is currently in the atmosphere. And while a single wildfire could undo decades, if not centuries, of sequestration in a forest, carbon stored in the ocean is less at risk of what a rocket scientist might call a rapid unplanned disassembly. As we look to remove billions of tons of historic emissions from the atmosphere, the sheer size of the ocean, covering 70% of the Earths surface, comes in handy. Theres a lot of momentum behind ocean-based carbon dioxide removal (CDR), with hundreds of startups clamoring for funding. But, as new research from climate non-profit Carbon180 lays out, the sector risks outpacing scientific knowledge and regulation. Because theres so much uncertainty, theres potential for irresponsible deployment of these types of carbon removal projects, Sifang Chen, author of the report, told me. We need to make sure safeguards are put in place. The paper lays out four major challenges faced by ocean CDR: a small knowledge base, insufficient governance, uncertain environmental and social impacts, and underdeveloped monitoring and verification processes. Governments need to create policies which will help advance research into these methods and prevent further harm being done to ocean ecosystems, which are already in a fragile state as a result of human meddling. The ocean draws down many tons of CO2 a year, having absorbed about 30% of whats emitted by burning fossil fuels so far. We can support that natural process by restoring and protecting ocean habitats and species. But were also likely to need some engineered removal methods, too: Direct ocean capture: This is akin to direct air capture, except instead of pulling CO2 out of the air, you pull the gas out of seawater. Ocean fertilization and seaweed farming: These methods rely on harnessing the power of photosynthesis to increase carbon uptake in algae seaweed or phytoplankton before sinking the biomass and storing it on the seafloor. Ocean alkalinity enhancement: This uses minerals or electrochemical reactions to increase the alkalinity of the ocean, improving the oceans capacity to absorb atmospheric CO2. Each technique comes with unique benefits, risks and downsides that scientists are still trying to fully understand. While its easy to calculate how much CO2 a direct ocean capture facility has removed and stored (via a process known as measurement, reporting and verification, or MRV), its also very energy intensive to pump water through a monitoring system. The MRV for alkalinity enhancement is a lot trickier, but it could help address ocean acidification one of the damaging impacts of the climate crisis. Getting MRV right is crucial to ensuring that these technologies have a positive climate impact. But its one of ocean CDRs largest knowledge gaps. David Ho, an oceanography professor at the University of Hawaii, has set up [C]Worthy, a non-profit organization, to develop MRV methods for a range of ocean CDR techniques. Its a complicated task. The ocean is one enormous open system and CDR can take place over long periods of time, making it hard to assess, Ho explains. Vassilis Kitidis of PML Applications Ltd., the commercial arm of Plymouth Marine Laboratory, argues that the conversation may be too CO2-centric. Certain ocean CDR methods particularly those relying on biomass growth could actually increase emissions of other more potent greenhouse gases, such as methane and nitrous oxide. You could end up in a perverse situation where you are storing carbon but contributing to global warming, Kitidis says. Its a reminder that before anything is rolled out at scale, theres a whole world of unknowns to quantify. The Carbon180 research also emphasizes the importance of engaging with coastal communities. Planetary Technologies, a Canadian CDR company, is running an ocean alkalinity enhancement test in Cornwall, England, but has faced protests and criticism from the local community. The test involves adding magnesium hydroxide to the ocean via a wastewater pipe. Neither Ho nor Kitidis (who has worked with the startup as an independent monitor) were worried about the environmental impacts of using the chemical, which is already widely used in antiperspirants and wastewater treatment, at such low doses. But its understandable that locals felt suspicious of the tests. Theres an incentive for companies to scale up quickly so they can start getting carbon credits on the market and generate returns for investors. Government funding into research could help address that issue, as startups could learn without feeling the need to recoup money. The USs Direct Air Capture Hubs scheme offers a template, with $3.5 billion of funding to develop large-scale facilities. Everyones first priority should be rapid decarbonization. But implemented correctly, ocean-based carbon dioxide removal could help right some of our historical wrongs. As the Carbon180 paper says: In order to build capacity for if and when ocean CDR deployment is needed in the future, efforts aimed at filling current knowledge gaps must start today. More From Bloomberg Opinion: We Cant Afford Tariffs on Chinese Solar Panels: Mark Gongloff Business and Nonprofits Can Wipe Out Carbon: Anne Finucane & Gina McCarthy Spains Heatflation Will Burn Our Wallets: Lara Williams (Adds that Plymouth Marine Laboratory has a commercial arm, in ninth paragraph.) This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners. Lara Williams is a Bloomberg Opinion columnist covering climate change. More stories like this are available on bloomberg.com/opinion 2023 Bloomberg L.P.