In kindergarten, I discovered that our planet has four oceans, the Atlantic, Pacific, Indian, and Arctic. But at a United Nations climate conference last summer in Bonn, Germany, I learned those four bodies of water actually constitute one diverse, intertwined whole.
At the Bonn meeting known as SB58, delegates highlighted the marine world’s critical role in meeting the climate crisis and devoted attention to ocean challenges in informal discussions. The conference was organized by the United Nations Framework Convention on Climate Change (UNFCCC) in preparation for the upcoming 28th Conference of the Parties or COP28, taking place from November 30 to December 12, 2023 in Dubai. But in a striking omission at SB58, negotiators avoided oceanic issues in official talks and failed to incorporate ocean-related solutions into UN climate policy.
To raise awareness of the climate threat to the marine ecosystem, Ambassador Peter Thompson of Fiji, the UN’s inaugural special envoy for the ocean, urged that the UN refer to the ocean in the singular. The diplomat said that language would underscore deep interdependencies among climate impacts across global regions. The reference also would reinforce that potential maritime solutions are connected and could have downstream effects throughout the world, he said.
The ocean has existing systems to fight climate change by absorbing carbon dioxide and cutting greenhouse gas emissions, regulating climate and weather patterns, and helping balance uneven levels of solar radiation reaching the earth. The UN recognizes that the ocean serves as an indispensable “sink” for carbon, absorbing approximately 25 percent of carbon dioxide emissions and about 90 percent of the heat these emissions release.
However, climate change is undermining marine capacity to provide this protection. Scientists and marine advocates have called for more aggressive efforts to shield the ocean from climate impacts, including ocean warming, ocean acidification, and sea level rise threatening human and wildlife survival, as well as human economies such as aquaculture, maritime tourism, and global trade. The Bloomberg Green newsletter reported this past July, dangerously high ocean temperatures exacerbate extreme weather around the world.
Despite the UN’s general recognition of the ocean’s essential role, the first global stocktake, a process currently underway to assess countries’ progress toward their Paris Climate Change Agreement goals, acknowledges “oceans” only minimally.
In light of this limited attention, climate experts highlighted ocean-based carbon dioxide removal (OCDR) as a type of geoengineering that remains underexplored. Forms of OCDR include increasing photosynthesis and enhancing ocean alkalinity to allow for increased carbon uptake.
In its latest Assessment Report (AR6), the Intergovernmental Panel on Climate Change (IPCC), which provides scientific assessments to the UN, concluded that carbon dioxide removal, whether ocean-based or land-based, “cannot substitute for immediate and deep emissions reductions,” but is vital for “limit[ing] global warming to 2 [degrees Celsius] or lower by 2100.”
However, scientists worry about implementing OCDR techniques which remain untested and pose unpredictable risks to local ecosystems and global marine systems. Tom Bell, a researcher at the Plymouth Marine Laboratory in the United Kingdom, summarized the key OCDR issues: whether these methods will remove carbon beyond decarbonization; how much, how quickly, and for how long carbon will stay isolated and stored; and what downstream effects sequestered carbon might have on ecosystems near and far.
Yet, despite their wariness, climate experts emphasized the need to achieve crucial temperature reduction goals by proceeding with caution. Thompson, the UN special envoy, acknowledged legitimate concerns about geoengineering, such as carbon dioxide removal, but argued climate change itself is a form of geoengineering that is already underway. Bell and other climate experts at Bonn urged the scientific community to set up sound frameworks and safeguards at this early stage because OCDR in the commercial sector will advance on its own.
One important tool in international climate action is a monitoring, reporting, and verification framework (MRV). The process directs each country to quantify and share its greenhouse gas outputs and removals and directs the UN to evaluate these reports against international climate goals. MRV can provide the UN a comprehensive and consistent understanding of countries’ progress.
In the meantime, ocean-based carbon dioxide removal is expected to arrive more fully on the negotiating table at COP28 in Dubai, and when it does, it will likely trigger intense debates over policy and semantics. In Bonn, I witnessed such diplomatic scrutiny during the final negotiations about language characterizing the IPCC and its AR6 assessment report. On one side, most negotiators wanted to promote the IPCC as the providers of the “best available science” and AR6 as “the most comprehensive and robust assessment of climate change to date.” On the other side, an opposing group rejected this language and proposed alternatives that minimized the IPCC’s work.
During the group’s final official meeting, the facilitator called for a 15-minute informal “huddle.” Negotiators broke from their table seats, where they had been dutifully raising their placards with their country’s name in order to have a turn to speak. At first, they gathered in small groups, but as the intended 15 minutes ticked down, everyone but the opposing country amassed at the back of the room. Finally, even the holdout country joined the “huddle.” I was fascinated to observe the debate, even though it failed immediately to resolve the issues.
Hours later, however, the negotiators settled on final wording. They deleted the line with “best available science” and demoted the other line to “more comprehensive and robust” than the previous assessment report. These edits represented the bending of a nearly unanimous majority to the interests of a powerful outstanding voice.
The ardor of negotiators tussling over seemingly straightforward text was eye-opening for me. I expect even more intensity when it comes to negotiations over a potential technological solution that is even more complex. Stay tuned to the vital topic of OCDR at COP28 in November and December.