{"id":380,"date":"2026-05-08T09:45:39","date_gmt":"2026-05-08T09:45:39","guid":{"rendered":"https:\/\/redzine.co.uk\/index.php\/2026\/05\/08\/the-ocean-is-fighting-climate-change-and-were-trying-to-help-it-heres-how\/"},"modified":"2026-05-08T09:45:39","modified_gmt":"2026-05-08T09:45:39","slug":"the-ocean-is-fighting-climate-change-and-were-trying-to-help-it-heres-how","status":"publish","type":"post","link":"https:\/\/redzine.co.uk\/index.php\/2026\/05\/08\/the-ocean-is-fighting-climate-change-and-were-trying-to-help-it-heres-how\/","title":{"rendered":"The ocean is fighting climate change and we\u2019re trying to help it \u2013 here\u2019s how"},"content":{"rendered":"
<\/span> Diliana Nikolova \/ shutterstock<\/span><\/span><\/figcaption><\/figure>\n

We replaced the stove with plywood, turning the kitchen of the dive boat into an impromptu research lab. Plugging in wires and connecting tubing, we assembled a scientific instrument within the cramped cabin. <\/p>\n

Then we cast off into Halifax Harbour, Canada, surveying the turquoise waters for signs of an unusual test: could we use the ocean itself to remove carbon dioxide from the air<\/a>?<\/p>\n

Carbon dioxide (CO\u2082) is the most important driver of climate change, but it cannot be seen. Its build-up in the atmosphere is gradual. Its worst consequences take time to emerge. Even if emissions fell sharply tomorrow, the CO\u2082 already released would continue to warm the planet<\/a>.<\/p>\n

That is why scientists and policymakers are increasingly turning to carbon dioxide removal (CDR): taking CO\u2082 that has already been released back out of the air. So far, most large-scale CDR has focused on land, such as reforestation. But land is finite, competes with food production and biodiversity, and stored carbon can be lost through fire or deforestation. As emissions continue to outpace what these approaches alone can manage, attention has turned toward the ocean.<\/p>\n

The overlooked role of the ocean in carbon storage<\/h2>\n

The ocean covers about 70% of the Earth\u2019s surface and holds roughly 50 times the amount of carbon found in the atmosphere<\/a>. Before the industrial revolution, carbon moved between air and sea in near balance. As industrial activity increased atmospheric CO\u2082, more of it dissolved into seawater and the ocean became more acidic. <\/p>\n

\n \"Person<\/a>
\n Katryna Niva sailing through Halifax Harbour, investigating the effects of enhancing ocean carbon storage.<\/span>
\n Katryna Niva<\/span><\/span>
\n <\/figcaption><\/figure>\n

All that dissolved carbon has resulted in the ocean storing about a third of human CO\u2082 emissions<\/a> since the industrial revolution \u2014 substantially slowing the pace of climate change. The emerging question is whether we can build on this natural service. The field exploring that possibility is known as marine carbon dioxide removal (mCDR).<\/p>\n

All mCDR approaches aim to reduce the amount of dissolved CO\u2082 at the ocean surface, converting it into more stable forms. When surface CO\u2082 is reduced, more CO\u2082 from the atmosphere dissolves into the sea.<\/p>\n

Reducing surface CO\u2082 \u2013 so the sea absorbs more<\/h2>\n

One approach involves adding alkaline minerals \u2013 often crushed or processed rocks like limestone or basalt \u2013 to seawater. This reduces acidity and increases the capacity of seawater to absorb more carbon and store it for centuries to come. This is the strategy under development by Planetary Technologies in Halifax Harbour, Canada. There, alkaline minerals have been introduced to seawater through the cooling water discharge pipe of a natural gas burning power plant. <\/p>\n

Another approach relies on biology. The ocean is filled with microscopic organisms that photosynthesise, using dissolved CO\u2082 to grow and reproduce. Some of this carbon sinks into deeper waters, through a process known as the \u201cbiological carbon pump\u201d. By adding the nutrients that these organisms need to thrive, this effort hopes to increase microorganism populations and, ultimately, strengthening the biological carbon pump.<\/p>\n

How do we know it works?<\/h2>\n

Whether chemical or biological, these approaches face the same questions: how much additional CO\u2082 is actually being removed from the atmosphere? And what are the ecological consequences?<\/p>\n

The processes involved are invisible to the naked eye. The organisms are microscopic. The carbon transformations are chemical. Yet if marine carbon removal is to scale to climate-relevant levels, it will require rigorous measurement, transparency and public trust.<\/p>\n

In the Cassar Lab<\/a> at Duke University, we develop instruments to detect subtle changes in seawater chemistry. They continuously measure dissolved gases and other tracers, allowing us to reconstruct what microorganisms are doing and how carbon is moving through the system. <\/p>\n

In August 2025, we deployed one of these tools in the turbulent waters surrounding one of the world\u2019s first coastal ocean alkalinity enhancement projects, off Nova Scotia, Canada. This instrument was a mass spectrometer that extracts and quantifies dissolved gases from seawater. These readings give us insight into the ecosystem\u2019s balance between photosynthesis and respiration \u2013 and therein, an understanding of how stressed or healthy the surrounding ecosystem is. Working alongside researchers tracking the chemical changes of the mCDR work underway, we focused on understanding how marine microorganisms were responding.<\/p>\n

Another instrument, known as the Gopticas<\/a>, allows a precise quantification of how much photosynthesis is happening in a seawater sample. The Gopticas was recently exhibited Prototypes for Humanity<\/a>, an international innovation initiative based in Dubai, highlighting how tools developed for fundamental oceanography can also underpin climate accountability. This allows stronger quantification of ecosystem health as well as carbon influx. <\/p>\n

A scalable approach to mCDR monitoring<\/h2>\n

We are now forming a team that can deploy these tools to directly quantify the amount of CO\u2082 being converted into longer-lived forms \u2013 and to spot early signs of ecological disruption.<\/p>\n

This kind of monitoring is crucial. It allows us to distinguish between carbon that is briefly cycled near the surface and carbon converted into forms likely to remain stored for centuries. It also provides early warning if an intervention begins to disrupt marine biology. The work in Halifax marked the first application of our instruments to mCDR initiatives, but we look forward to applying these same approaches across regions and mCDR approaches.<\/p>\n

\n \"Plume<\/a>
\n The alkalinity plume in the waters of Halifax Harbor, Canada.<\/span>
\n Katryna Niva<\/span><\/span>
\n <\/figcaption><\/figure>\n

Developing robust methods to quantify both carbon removal and ecological impact before large-scale deployment is essential. Without credible verification, claims of carbon removal risk outpacing evidence. And without clear evidence of environmental safety, public support will falter.<\/p>\n

If marine carbon dioxide removal is to make a meaningful contribution to climate mitigation, it must rest on precise measurement and accountability. Governments, regulators and investors will need confidence that reported carbon removal is real and durable \u2013 and that marine ecosystems are protected.<\/p>\n

Standing on the deck of the dive boat, staring out at the plume of alkaline waters emerging from the pipe, it\u2019s easy to be struck by a feeling of awe. This experiment is tiny compared to global climate change \u2013 a drop in the ocean. But it offers a glimpse into a more optimistic future.<\/p>\n

\n

This article was commissioned in conjunction with Prototypes for Humanity<\/a>, a global initiative that showcases and accelerates academic innovation to solve social and environmental challenges. The Conversation was a media partner of Prototypes for Humanity 2025.<\/em><\/p>\n

\"The<\/p>\n

Katryna Niva works for Duke University. Her research is also supported in part by the Carbon to Sea Initiative. <\/span><\/em><\/p>\n

This article was commissioned in conjunction with Prototypes for Humanity, a global initiative that showcases and accelerates academic innovation to solve social and environmental challenges. The Conversation was a media partner of Prototypes for Humanity 2025<\/span><\/em><\/p>\n

Alireza Merikhi does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.<\/span><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Diliana Nikolova \/ shutterstock We replaced the stove with plywood, turning the kitchen of the dive boat into an impromptu research lab. Plugging in wires and connecting tubing, we assembled a scientific instrument within the cramped cabin. Then we cast off into Halifax Harbour, Canada, surveying the turquoise waters for signs of an unusual test: […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-380","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts\/380","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/comments?post=380"}],"version-history":[{"count":0,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/posts\/380\/revisions"}],"wp:attachment":[{"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/media?parent=380"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/categories?post=380"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/redzine.co.uk\/index.php\/wp-json\/wp\/v2\/tags?post=380"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}