Fusing urban informatics and weather modelling in digital twins for city-scale heat-health mapping

Abstract

Urban expansion and population growth intensify the Urban Heat Island (UHI) effect, increasing energy demands for cooling and amplifying public health risks, particularly when compounded by extreme weather events such as heatwaves. This study introduces a conceptual framework for Urban Digital Twins (UDTs) to assess and mitigate UHI impacts by integrating advanced urban informatics, high-resolution atmospheric modelling, and 3D visualisation. Using Sofia, Bulgaria, as a case study, the framework incorporates energy consumption data and street-level urban features, including tree cover and solar radiation, combined with the Weather Research and Forecasting (WRF) model simulations to characterise the urban thermal environment. The outputs are translated into public health metrics, such as the Wet Bulb Globe Temperature (WBGT), and visualised in 3D to identify high-risk areas, thereby informing decision-making for residents and policymakers. The modelling system was rigorously calibrated and validated through case studies, demonstrating strong accuracy in simulating urban thermal dynamics and associated health risks. Results highlight critical zones in central Sofia where WBGT exceeded 25.2 °C at 1600 LST on 22 August 2018, indicating moderate-to-high daily activity levels and potential discomfort for residents. The proposed framework supports climate-sensitive urban planning by linking surface thermal exposure, energy use, and public health vulnerability, and demonstrates scalability for application across diverse urban environments under current and future climate conditions.

Keywords

Temperature / Energy / Urban heat islands / WBGT / WRF model / Urban digital twin / Urban informatics

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Funding

H2020 WIDESPREAD-2018-2020 TEAMING Phase 2 (857155)

“Research, Innovation and Digitalisation for Smart Transformation” 2021-2027 (PRIDST) (BG16RFPR002-1.014-0010-C01)

Driving Urban Transitions (DUT) (KP-06-D002/5)

RIGHTS & PERMISSIONS

The Author(s)