UrbanAIR

The project runs from 1 January 2025 to 31 December 2028 with 14.2 million euros of EU funding (grant agreement 101188131).^1,10 Delft University of Technology coordinates eighteen partners in eleven countries, including the weather service KNMI, the research centre VITO and Arup.^1,10 ECMWF and EUMETSAT sit on its advisory board.³ UrbanAIR is one of three projects funded under the call "New digital twins for Destination Earth"; the other two are TerraDT and WeatherGenerator.³

Antwerp and Barcelona are the two "action cities": they steer the design and test the tools. Paris, Bristol and Rotterdam are "learning cities" that contribute data and use cases.^1,2 The aim is to show city teams where heat and pollution concentrate, which groups are most exposed, and what greening, cooling networks, zoning or traffic measures would change.^1,2 The project calls its way of working a living lab: city teams guide the design, and prototypes are tested on the ground.^1,2

The system is modular. Destination Earth forecasts are joined to high-resolution urban models that simulate airflow, pollution and infrastructure impacts at the building scale.² Physics models at several levels of detail trade speed against precision; the project lists LES, RANS and analytical models.² LES and RANS are two ways of simulating turbulent airflow, LES the finer and slower of the two. Machine-learning emulators, fast stand-ins trained on a slower model's output, cut the run times.² Uncertainty is estimated statistically.² An agent-based model, which simulates many individuals each acting on simple rules, represents how people respond to heat, alerts and pollution.² Street-level air quality is modelled at 100 to 200 metres.²

KNMI simulated the June 2026 heatwave over Rotterdam and Antwerp with the HARMONIE-AROME weather model at 200 metres, then re-ran it under a climate 3 degrees warmer.⁷ A University of Freiburg study of pedestrian heat stress in Freiburg worked at one-metre resolution.⁸ It was published in PLOS Climate in 2026, with its data and model code on Zenodo.⁸ A publications page lists papers and datasets from 2025 and 2026.⁴

Data and models run in the Destination Earth data lake through Jupyter notebooks, object stores and the Islet cloud.⁶ A demonstration ran VITO's models for Antwerp in a notebook in the data lake. The UKRI STFC Scientific Computing team is now working with Barcelona and Paris.⁶