Race to Save the Planet: Can Ocean Dumping Tackle Climate Change and Lock Away Carbon?

oleh admin | Mar 24, 2025 | climate change, ecology, environmental science, environmentalism, sustainability

A lesser-known firm based at a natural-gas-powered facility along the east coast of Canada is injecting a mixture of minerals into the sea as part of an effort to combat global warming.

The question of whether salvation for our planet lies in combating pollution or finding a miraculous solution might vary depending on who you inquire with.

From the shoreline, a pipeline discharges a blend of water and magnesium oxide — a fine white powder utilized in various applications ranging from building materials to antacid medications. Planetary Technologies, headquartered in Nova Scotia, is counting on this compound to sequester additional heat-trapping emissions into the ocean.

“Reverse the climate. Mend the ocean,” is inscribed on a nearby shipping container.

The sector of ocean carbon capture is expanding rapidly.

Planetary is part of an expanding sector striving to develop solutions for global warming by harnessing the ocean’s absorptive capabilities.

Backed by $1 million (€922,875) from Elon Musk’s foundation, it is now vying for an additional prize of $50 million (€46 million).

Many other businesses and research institutions are advocating the same idea: that submerged rocks, marine nutrients, agricultural residues, or offshore algae might sequester heat-trapping carbon dioxide for hundreds of years or even longer.

In the last four years, almost 50 field tests have been conducted, with startup companies securing several hundred million dollars in initial funding.

However, the field is still filled with debates about the impacts on the oceans if these strategies are implemented on a larger scale, as well as uncertainties regarding their precise benefits for the climate. Critics argue that the initiatives are progressing too rapidly without sufficient safeguards in place.

“It feels akin to the Wild West era. Everyone seems to be joining in, and everyone has ideas they want to implement,” stated Adina Paytan, an earth and ocean sciences professor at the University of California, Santa Cruz.

Planet, similar to many ocean-focused start-ups, is funding its operations by selling

carbon credits

– or tokens signifying the removal of one metric ton of carbon dioxide from the atmosphere. Unregulated and heavily discussed, carbon credits have gained popularity this century as a means for businesses to buy offsets instead of decreasing their own emissions. These credits typically cost a few hundred dollars each.

Last year, over 340,000 marine carbon credits were sold within the sector, marking an increase from merely 2,000 credits four years prior, as reported by CDR.fyi. However, this quantity represents only a minuscule portion of the total carbon sequestration needed to maintain Earth’s habitability for future generations, according to scientific estimates.

The individuals at the forefront of these initiatives, such as Will Burt, who serves as Planetary’s lead ocean scientist, recognize they’re venturing into unknown waters—but argue that the greater risk for our planet and seas lies in not acting swiftly enough.

We need to determine whether it will be successful or not. The sooner we figure this out, the better.

Suctioning carbon into the ocean

Efforts to

capture carbon dioxide

have increased dramatically in recent years.

Many current climate models indicate that merely reducing emissions will not suffice to halt global warming, says the United Nations’ Intergovernmental Panel on Climate Change. It is essential for the planet to also extract greenhouse gases from the atmosphere, with the ocean being a potential site for this removal process.

Funds have already been allocated to various approaches on land—including,

extracting carbon dioxide from the atmosphere

, constructing facilities for underground carbon storage and restoring forests, which inherently capture CO2.

However, numerous initiatives face constraints due to available space and have the potential to affect adjacent neighborhoods. The ocean naturally controls our planet’s climate through heat and carbon absorption, making it appear virtually boundless when contrasted with terrestrial limitations.

“Could that extensive surface area be utilized as a strategy to address and lessen some of the most severe impacts of climate change?” questioned Adam Subhas, who heads a carbon removal initiative at the Woods Hole Oceanographic Institution located in Cape Cod, Massachusetts.

On an Tuesday afternoon at the outskirts of Halifax Harbour, Burt removed his bicycle helmet and put on a hard hat to provide two engineering students with a tour of Planetary’s location.

A separate truck trailer was positioned in an open area, holding large sacks of magnesium oxide that had been extracted in Spain and transported via the Atlantic to Canada.

Many businesses seeking offshore climate solutions aim to decrease or alter the carbon dioxide contained within the ocean. According to Burt, accomplishing this would enable the oceans to function “as a vacuum,” pulling additional gases out of the atmosphere.

Planetary is employing magnesium oxide to generate the required vacuum. Once mixed with seawater, this substance converts carbon dioxide from its gaseous state into stable compounds that will not react with the atmosphere for millennia. Similarly, limestone, olivine, and other alkaline rocks achieve the same outcome.

Other firms are concentrating on cultivating seaweed and algae to absorb gases. Similar to terrestrial plants, these aquatic organisms take in carbon dioxide from the sea, much like how trees absorb CO2 from the atmosphere. For example, the firm Gigablue has started pumping

nutrients

In New Zealand’s waters, these tiny organisms called phytoplankton can thrive where they would not be able to survive otherwise.

Others see the deep sections of the ocean as a repository for organic matter that could release greenhouse gases if kept above water.

Firms have submerged wooden chips along Iceland’s coastline and intend to deposit Sargassum, a light brown algae, into deep waters. Carboniferous, a new company, is applying for a federal license to position sugar cane residue at the base of the Gulf of Mexico, which President Donald Trump has named the Gulf of America.

Although Planetary’s project might seem like “a scary scientific experiment,” according to Burt, the firm’s tests indicate that magnesium oxide presents negligible risks to marine life, including plankton and fish. This substance has historically been utilized in water treatment plants and various industries for neutralizing acidity in water.

Halifax Harbour represents only one of the locations where Planetary aims to conduct operations. Additionally, the firm has established a presence at a wastewater treatment facility along the coast of Virginia and intends to commence tests in Vancouver before the end of this year.

As stated by the National Academies of Sciences, Engineering, and Medicine, the sector must eliminate billions of tons of carbon dioxide annually by the middle of this century to achieve the climate targets established almost ten years prior during the

Paris climate agreement

.

The main objective is to address the swiftly escalating climate crisis,” Burt stated. “While we must proceed with caution and honesty, it is crucial that we take action quickly.

Local communities are ‘tangled up in turmoil’

Although there is widespread excitement within the sector, coastal towns often hesitate to join in.

In North Carolina, a proposal to unload shipments of olivine close to the coastal community of Duck led to inquiries that reduced the scale of the initiative by over fifty percent.

The firm Vesta, established in 2021, advocates for the use of the blue-green mineral as a means to sequester carbon within the ocean and generate structures that protect shoreline communities from storms and wave action.

Throughout the permit application stage, representatives from the state Wildlife Resources Commission, the Division of Marine Fisheries, and the US Fish and Wildlife Service voiced numerous reservations.

As suggested, the initiative is intended as a brief investigation but has the possibility of leading to significant long-term effects without any outlined corrective measures,” noted a field supervisor from the Fish and Wildlife Service. Both organizations expressed concerns that olivine might suffocate the seabed community and pose risks to an area crucial for sea turtle populations and Atlantic sturgeon.

Tom Green, the CEO of Vesta, stated that the company did not anticipate its initial submission would get approval without modifications. “This marks the beginning of an ongoing conversation with both regulatory bodies and the public,” he explained.

Last summer, the initiative moved ahead with a significantly reduced scale, focusing on a restoration strategy along with enhanced monitoring criteria for deep-water organisms. Currently, eight thousand tons of olivine transported from Norway lie below the waters off North Carolina’s coast.

Green acknowledged his awareness of public skepticism and emphasized that Vesta aims to protect the environment rather than cause damage. He stated that it is their responsibility as a company “to be present in local communities, engage directly, and share our findings” with the intention of fostering trust through open communication.

Communities reliant on fishing have objected to yet another climate initiative headed by Subhas from the Woods Hole Research Center, which has sparked 10 months of discussion and argument.

The initially suggested plan from last spring entailed releasing approximately 66,000 gallons of sodium hydroxide solution into the sea close to Cape Cod. Later, Woods Hole revised their proposal to utilize under 17,000 gallons of this substance, though federal authorization for the scaled-back version remains unconfirmed.

In two distinct assessments, the Environmental Protection Agency stated that it considers the project’s scientific value to be greater than the potential environmental risks. They also indicated that they do not anticipate “any unacceptable effects” on water quality or fisheries.

However, fifth-generation fisherman Jerry Leeman III seeks answers about how the lobster, pollock, and flounder eggs floating within the water column and across the ocean’s surface might be affected when exposed to such potent chemicals.

“Are you instructing all the fishermen not to fish in this region during your project? And who provides compensation for those being displaced?” he asked.

Subhas’ group anticipates that the strongest effects of the chemical will persist for under two minutes in the sea due to dilution. Additionally, they have committed to postponing or moving the initiative if clusters of fish or areas with fish eggs are observed nearby.

Sarah Schumann, a commercial fisher from Rhode Island specializing in bluefish and an advocate for “climate-friendly” fisheries, expressed uncertainty about balancing her backing of scientific research with the concerns voiced within the fishing community after participating in four listening sessions.

“If I were really attempting to make up my mind about this matter, I’d be quite conflicted,” she stated.

Moreover, while Planetary encountered minimal opposition from residents around Halifax Harbour, the company confronted numerous protests regarding a climate initiative they suggested in Cornwall, England.

Last April, over a hundred individuals walked alongside a beach holding placards that said “Maintain our ocean as chemical-free.”

Sue Sayer, who leads a team researching seals, mentioned during conversations with Planetary that they were unaware “of the various animal and plant species inhabiting St. Ives Bay.” She stated that this lack of knowledge ignited a local community known for being “extremely scientifically engaged when it comes to marine life,” particularly following the firm’s first discharge of magnesium hydroxide into the bay.

David Santillo, a senior scientist working for the Greenpeace Research Laboratories at the University of Exeter, criticized the methodology used by Planetary to monitor the effects of their initiatives. In a recording reviewed by The Associated Press, it was revealed that the initial data collected by the firm in Cornwall came from only a handful of days.

If you lack a benchmark established over several years and seasons,” Santillo stated, “it becomes impossible to determine whether you can identify any of your impacts.

A review carried out by the United Kingdom’s Environment Agency determined that Planetary’s trials presented a “minimal” threat to oceanic organisms, along with a possibility of substantial carbon extraction.

Nevertheless, the firm decided to temporarily halt its plan to inject an additional 200 metric tons of minerals. In compliance with governmental advice, Planetary announced it would look for a local supplier of magnesium hydroxide near the Cornwall location instead of importing it from China. The company also pledged not to trade carbon credits derived from previous chemical emissions in the area.

Sara Nawaz, who serves as the research director at American University’s Institute for Responsible Carbon Removal, expressed her understanding of why scientists often find it challenging to engage with communities and secure their backing. Initial studies indicate that people are hesitant about the concept of carbon removal.

“engineering” the climate

.

She noted that many individuals feel a deep emotional bond with the sea. They worry that anything placed in the ocean “cannot be retrieved.”

The unanswered questions: Can the technology function properly?

Not only local residents but also scientists have doubts about the effectiveness of these technologies. Despite this, many underlying concepts have been researched for several decades. However, laboratories can replicate real-world conditions only up to a certain extent.

At a recent Environmental Protection Agency hearing regarding the Woods Hole initiative, many oceanographers along with representatives from various industries voiced their opinion that it’s essential to conduct large-scale sea trials now.

“There’s a pressing need to proceed with this research,” stated Ken Buesseler, another Woods Hole researcher focusing on the carbon sequestered by algae.

Despite this, the ocean remains a vibrant and complex environment for research. Researchers continue to discover fresh insights into its role in absorbing and recycling carbon. Any substances introduced into the sea have a high chance of sinking, dispersing, or being carried elsewhere, complicating attempts to monitor the ocean’s reactions.

“It’s extremely challenging to make the ocean behave as desired,” remarked Sarah Cooley, a carbon cycle scientist with experience at both the nonprofit organization Ocean Conservancy and within the federal government.

Katja Fennel, who leads the oceanography department at Dalhousie University, focuses her efforts on modeling the amount of carbon captured by Planetary in Halifax Harbour—a figure that carries certain uncertainties.

She shares leadership duties with others for a team of scholars that keeps an eye on the firm’s initiative through water specimens, measuring devices, and core sediments collected from various spots across the bay. On certain occasions, her crew introduces a reddish dye into the pipelines to observe how the minerals break down and make their way toward the ocean.

Fennel mentioned that the models are essential for simulating scenarios where Planetary takes no action. Additionally, these models are crucial due to the vastness and depth of the ocean, which make it impractical to gather sufficient data to fully understand it.

“We cannot measure everything at once,” she stated.

For how long is the carbon sequestered?

Doubts still remain regarding the duration for which the captured carbon will persist.

This is particularly crucial for businesses dealing with algae, wood chips, or other organic substances since their decomposition location can significantly impact whether they emit carbon dioxide back into the environment.

As plants and algae descend deeper, they store more carbon over extended periods. However, achieving this consistently isn’t straightforward. Running Tide, which previously deployed almost 20,000 tons of wood chips into Iceland’s seas before closing down, claimed that the captured carbon might remain stored anywhere from just half a century up to around three thousand years.

Despite their effectiveness over the long term, many businesses operate on such a limited scale that they cannot significantly impact the climate. Achieving present-day climate objectives would require enormous quantities of resources, energy, and capital to expand operations sufficiently.

“The question is, how does this change when scaled up to billions of tons annually?” asked David Ho, an oceanography professor at the University of Hawaii at Manoa and co-founder as well as chief science officer of the non-profit organization (C)Worthy, whose mission involves assessing the effects of marine-based carbon extraction. “That remains to be seen,” he added.

Planetary’s Burt envisions a scenario where minerals are extracted via power plants and water treatment centers located along all significant coastlines globally. However, this would necessitate a substantial, consistent supply of magnesium oxide or comparable minerals, as well as the necessary energy for mining and transporting these materials.

The proliferation of seaweed and algae would have to increase dramatically. According to estimates from the National Academies of Sciences, Engineering, and Medicine, approximately two-thirds of the global coastlines might require being bordered by these organisms.

kelp

To start making progress against global warming, the company Seafields, which is conducting trials in the Caribbean, proposes establishing a Sargassum farm stretching over 300 kilometers between Brazil and West Africa.

The expansion might worsen environmental damage that can go unnoticed in smaller tests, with consequences potentially spreading worldwide due to global water circulation.

However, the option of not attempting to address this issue means we will face unmitigated climate change, according to Ho.

The world is rapidly running out of time.

At the end of last year, Planetary revealed that its initiative in Nova Scotia effectively sequestered 138 tons of carbon dioxide—enabling the issuance of precisely 138 carbon credits to two initial backers of the firm, namely Shopify and Stripe.

Making money from their research makes many people who study the ocean uneasy.

“On one side, it promotes additional research and scientific inquiry, which is positive. Conversely, it also creates opportunities for exploiting the system,” stated Professor Paytan from Santa Cruz, who has received inquiries from multiple start-ups seeking collaboration.

She highlighted firms that allegedly exaggerated their carbon capture efforts, even as they boasted about regenerating rainforests in Peru and substituting soot-emitting cookstoves in Africa.

However, lacking additional government-sponsored research, numerous firms informed the Associated Press that there seems to be scarcely any means for the sector to progress.

selling credits

.

“Regrettably, that’s how we’ve structured it currently, leaving the development of these techniques to these startup companies,” explained Ho.

In his shipping container office near Halifax Harbour, Burt acknowledged the concerns surrounding the sale of credits. He emphasized that Planetary prioritizes transparent, responsible, and careful operations. However, he also pointed out that there is a necessity for startup companies to be more agile compared to academic institutions.

“We can’t examine this solution at the pace we’ve been analyzing the issues,” he stated. He believes there isn’t sufficient time for this.

Last year marked the

warmest year ever recorded in Earth’s history

, despite projections indicating that global carbon emissions will hit yet another record high.

“We need to reduce emissions urgently, drastically,” said Fennel, the researcher studying Planetary’s project. “Any removal of CO2 from the atmosphere is much more difficult and costly than avoiding CO2 emissions to begin with.”

The sector remains in motion. In February, Planetary announced that they had stored a cumulative amount of 1,000 metric tons of carbon dioxide within the ocean. Meanwhile, Carboniferous conducted their initial experiment involving depositing sugarcane onto the seabed earlier this year. Also recently, Gigablue entered into an agreement to secure 200,000 carbon credits aimed at distributing nutrient-rich particulates into the sea.

An increasing number of businesses are employing electricity to modify seawater molecules, aiming to encourage the ocean to sequester additional amounts of carbon dioxide. Recently, the startup Ebb Carbon entered into an agreement with Microsoft to supply as many as 350,000 carbon credits. Additionally, Captura, backed partly by financiers connected to oil and gas extraction, has extended its activities from California to Hawaii.

It remains uncertain whether the US government will hinder or endorse ocean climate efforts moving ahead. As the Trump administration aims to dismantle numerous environmental rules, the policy environment keeps changing.

reevaluate the scientific conclusion indicating that greenhouse gases pose a risk to public well-being

.

Although White House advisor Musk has softened some of his previous comments regarding climate change, his organization pledged $100 million (€92.2 million) four years ago to sponsor an award for the most effective approach to capturing carbon. Planetary is currently vying for this top honor.

The victor will be revealed on 23 April, which falls the day following Earth Day.