EU cities plan to compensate for a fifth of their emissions through carbon removal, but few have thought through how

EU cities plan to compensate for a fifth of their emissions through carbon removal, but few have thought through how Gaby Clark Scientific Editor Robert Egan Senior Editor An analysis of 103 European cities' climate-neutral plans for 2030 (including 22 capital cities) shows that municipalities are planning to rely on carbon removal to compensate for about a fifth of their emissions. This would mean removing roughly 61 million tonnes of emissions from the atmosphere—close to Austria's annual emissions. The study, published in Nature Climate Change, was led by the Joint Research Centre of the European Commission and included scientists at the Potsdam Institute for Climate Impact Research. It reveals that the majority of cities' residual emissions are in the energy and transport sectors (medians of 50% and 31%, respectively), despite both being considered easy to abate. The authors say this raises concerns about strategy effectiveness, urban constraints and strict timelines, warning that the cost and speed of action may be prioritized over transformative change. "These cities are pursuing extremely ambitious decarbonization targets, which is to be applauded and should serve as an inspiration to others. But they are using vague criteria to determine where residual emissions will come from, and might not have given enough consideration to options that would eliminate these emissions in the first place," commented PIK scientist and co-author of the study Quirina Rodriguez Mendez. The study develops an index to measure the robustness of residual-emission strategies—the RESRI index—which points to weaknesses in monitoring and quantifying how much carbon dioxide removal is available in cities and when. Current estimates for carbon removal capacity cover only 18% of total residual emissions. "It's really important that these removals actually happen and are transparently accounted for so that bad practice doesn't reduce them to mere hot air," Rodriguez Mendez said. The study offers best practices and makes concrete suggestions for city policymakers to evolve from existing plans, including front-loading emissions reductions to concentrate residual emissions exclusively in hard-to-abate sectors. The authors also suggest implementing demand-side measures, which could reduce emissions by 40–80%, depending on the context. Robust carbon removals matter The study shows that the 103 cities analyzed overwhelmingly rely on land-based carbon removals, such as tree planting, which raises concerns about permanence and land availability in urban environments, where competing needs for housing, health and energy restrict the area available for green spaces. The study notes that current climate-neutral plans do not include detailed land availability assessments. Permanent carbon removal is less prevalent in cities' plans, with only 32% mentioning it, including bioenergy carbon capture and storage (27%), biochar (13%) and direct air carbon capture and storage (7%). Carbon credits feature in 40% of plans but are often poorly specified, used as a last resort and met with widespread distrust by cities themselves. The study suggests that for climate neutrality to be achieved and maintained, cities may have to gradually complement temporary carbon dioxide removal with more permanent options. But this would require regulatory clarity, infrastructure development and predictable support, especially for permanent carbon removals, all of which would depend on national and even international governance bodies working together. Publication details Empirical insights into residual emissions in urban net-zero targets., Nature Climate Change (2026). DOI: 10.1038/s41558-026-02691-0 Journal information: Nature Climate Change Provided by Potsdam Institute for Climate Impact Research