biostudies-literatureFeng MÉcole Nationale d'Ingénieurs de Saint-Etienne (National Engineering School of Saint-Étienne)École Nationale d'Ingénieurs de Saint-EtienneNational Natural Science Foundation of ChinaNational Key Research and Development Program of ChinaNational Natural Science Foundation of China (National Science Foundation of China)3065https://www.ebi.ac.uk/biostudies/studies/S-EPMC10224944biostudies-literatureUnknown14(1)Denitrification and leaching nitrogen (N) losses are poorly constrained in Earth System Models (ESMs). Here, we produce a global map of natural soil ¹⁵N abundance and quantify soil denitrification N loss for global natural ecosystems using an isotope-benchmarking method. We show an overestimation of denitrification by almost two times in the 13 ESMs of the Sixth Phase Coupled Model Intercomparison Project (CMIP6, 73 ± 31 Tg N yr^-1), compared with our estimate of 38 ± 11 Tg N yr^-1, which is rooted in isotope mass balance. Moreover, we find a negative correlation between the sensitivity of plant production to rising carbon dioxide (CO₂) concentration and denitrification in boreal regions, revealing that overestimated denitrification in ESMs would tNature communicationsOverestimated nitrogen loss from denitrification for natural terrestrial ecosystems in CMIP6 Earth System Models.PMC102249444172210141830643Goll DSFang YFeng MCiais PXi YPeng SWang YChang JHoulton BZSun YLiu GfalseOverestimated nitrogen loss from denitrification for natural terrestrial ecosystems in CMIP6 Earth System Models.Denitrification and leaching nitrogen (N) losses are poorly constrained in Earth System Models (ESMs). Here, we produce a global map of natural soil ¹⁵N abundance and quantify soil denitrification N loss for global natural ecosystems using an isotope-benchmarking method. We show an overestimation of denitrification by almost two times in the 13 ESMs of the Sixth Phase Coupled Model Intercomparison Project (CMIP6, 73 ± 31 Tg N yr^-1), compared with our estimate of 38 ± 11 Tg N yr^-1, which is rooted in isotope mass balance. Moreover, we find a negative correlation between the sensitivity of plant production to rising carbon dioxide (CO₂) concentration and denitrification in boreal regions, revealing that overestimated denitrification in ESMs would t2023-01-01T00:00:00Z2023 May2025-05-29T16:22:21.228Z2025-05-29T16:22:21.228ZS-EPMC102249443724489610.1038/s41467-023-38803-z