UPDATE: A new report just released during COP30 warns of significant risks associated with using oceans as carbon sinks. Experts from the Norwegian University of Science and Technology emphasize that current technologies for marine carbon removal are too uncertain to be safely scaled up. With the critical 1.5°C threshold looming, researchers urge immediate focus on reducing emissions over unproven ocean strategies.
The report, presented at the UN climate conference in Brazil on November 20, 2025, highlights the need for stringent monitoring and verification before implementing marine carbon dioxide removal techniques. Helene Muri, a senior researcher involved in the study, stated, “The oceans can be part of the climate solution, but we need to strengthen the way we safeguard them before we scale things up.”
As global temperatures rise faster than anticipated, the urgency to address climate change has intensified. UN Secretary-General António Guterres noted that an overshoot of the 1.5°C limit is unavoidable if no immediate action is taken. “The 1.5°C limit is a red line for humanity,” he warned during his opening remarks at COP30.
The report underscores that while ocean-based carbon removal methods hold potential, they come with considerable uncertainty. Techniques such as enhancing plankton and seaweed growth or employing direct carbon extraction from seawater must be approached with caution. Without robust safeguards, these methods risk causing more harm than good.
“Immediate action must focus on approaches already known to work, namely cutting emissions,” Muri stressed. The European Marine Board’s findings reveal that proven strategies for emissions reduction should remain the priority as countries strive for net-zero emissions by 2050.
Despite progress in some carbon removal technologies, many remain experimental. “None of these methods are mature to use if you cannot verify impacts or where the carbon goes,” Muri explained. Establishing reliable standards for monitoring and reporting is critical as nations explore marine carbon removal’s potential.
The urgency of this issue cannot be overstated. Global CO2 emissions reached 42.4 gigatons in 2024, according to the CICERO Center for International Climate Research. As certain sectors, like aviation, prove difficult to decarbonize, carbon removal technologies may be necessary to balance remaining emissions.
Looking ahead, Muri emphasized that while marine carbon removal is not a “miracle ocean fix for climate change,” it remains a potential tool in the fight against global warming. However, “if we want to go in that direction, then we need to clear up all these standards and establish these properly before we can scale things up.”
As the climate crisis escalates, the conversation around ocean-based solutions must prioritize safety and verification. This report serves as a critical reminder to policymakers and researchers alike: while innovation is essential, we must first ensure that our methods protect the planet. Stay tuned for further updates on this developing story.
