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- Published: 21 January 2026
Scientific Data , Article number: (2026) Cite this article
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Abstract
Air pollution is the leading environmental threat to public health. Despite their value in raising awareness and improving access to complex data, street-level air quality platforms remain scarce. Moreover, uncertainty in high-resolution air po…
- Data Descriptor
- Open access
- Published: 21 January 2026
Scientific Data , Article number: (2026) Cite this article
We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.
Abstract
Air pollution is the leading environmental threat to public health. Despite their value in raising awareness and improving access to complex data, street-level air quality platforms remain scarce. Moreover, uncertainty in high-resolution air pollution estimates is rarely reported. This study presents six years (2019–2024) of nitrogen dioxide (NO2) concentration data for Barcelona (Spain), along with spatial maps of associated uncertainty. Besides providing high-resolution annual estimates (25 m × 25 m), the database includes daily NO2 concentrations at census-tract level, enabling temporal assessments with full spatial coverage citywide for the first time. The incorporation of uncertainty estimates represents a milestone for open street-scale air quality data and supports applications in health research, urban planning, and regulatory compliance. Finally, exceedance probability maps are provided, aligned with daily and annual NO2 thresholds defined by the European Air Quality Directives (2008/50/EC and 2024/2881) and 2021 WHO guidelines. The database is accessible through the uncertAIR platform, offering information to citizens, policymakers, and scientists in Barcelona, while serving as a reference for worldwide open data platforms reporting uncertainty.
Data availability
The datasets associated with this study are openly available in a Zenodo repository, with https://doi.org/10.5281/zenodo.16737065. Moreover, the datasets are accessible through the uncertAIR platform (https://earth.bsc.es/shiny/uncertAIR/).
Code availability
The source code for reference is available via Zenodo10.
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Acknowledgements
We acknowledge support from the Barcelona City Council through the UncertAIR project (ID 22S09501-001; Recerca Jove i emergent 2022), as well as support from the Ministerio de Ciencia, Innovación y Universidades (MICINN) as part of the VITALISE project (PID2019-108086RA-I00) funded by the MCIN/AEI/10.13039/501100011033. This work has received funding from the European Union’s Horizon Europe Research and Innovation Programme under the project UrbanAIR (grant agreement No. 101188131). A.C. acknowledges the support from the predoctoral program AGAUR-FI grants (2025 FI-3 00065) Joan Oró of the Department of Research and Universities of the Government of Catalonia, with co-financing from the European Social Fund Plus. C.C. acknowledges her AI4S fellowship within the “Generación D” initiative by Red.es, Ministerio para la Transformación Digital y de la Función Pública, for talent attraction (C005/24-EDCV1), funded by NextGenerationEU through PRTR. BSC researchers thankfully acknowledge the computer resources at Marenostrum provided by Barcelona Supercomputing Center (RES-AECT-2023-3-0018, RES-AECT-2024-1-0002) and the technical support of Miriam Olid and Tanmoy Mukherjee. A.C. acknowledges the Communication Team of the Earth Sciences Department of BSC, especially María José Llinares León, for their help in creating Fig. 1.
Author information
Authors and Affiliations
Barcelona Supercomputing Center, Barcelona, Spain
A. Criado, C. Carnerero, A. Frangeskou, D. Urquiza, A. Soret, M. Guevara, O. Jorba & J. M. Armengol 1.
Institute of Environmental Science and Technology (ICTA-UAB), Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
A. Criado 1.
Department of Fluid Mechanics, Universitat Politècnica de Catalunya, Barcelona, Spain
J. M. Armengol
Authors
- A. Criado
- C. Carnerero
- A. Frangeskou
- D. Urquiza
- A. Soret
- M. Guevara
- O. Jorba
- J. M. Armengol
Contributions
A.C. wrote the manuscript with support from J.M. and C.C. A.C. developed the code, performed the analytical calculations, and managed and maintained the database. A.C., J.M., and C.C. analysed the results. A.F. and D.U. conducted the user research. A.C. and A.F. developed and maintained the uncertAIR platform. M.G. worked on the emissions for the CALIOPE model. J.M., O.J. and A.S. supervised the different projects and secured funding. All authors reviewed the manuscript.
Corresponding authors
Correspondence to A. Criado or J. M. Armengol.
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Criado, A., Carnerero, C., Frangeskou, A. et al. Street- and census-level NO2 data for Barcelona with uncertainty and exceedance probability mapping. Sci Data (2026). https://doi.org/10.1038/s41597-026-06592-x
Received: 02 September 2025
Accepted: 08 January 2026
Published: 21 January 2026
DOI: https://doi.org/10.1038/s41597-026-06592-x