URock 2023a: an open-source GIS-based wind model for complex urban settings

Abstract

URock 2023a is an open-source diagnostic model dedicated to wind field calculation in urban settings. It is based on a quick method initially proposed by Röckle (1990) and already implemented in the proprietary software QUIC-URB. First, the model method is described as well as its implementation in the free and open-source geographic information system called QGIS. Then it is evaluated against wind tunnel measurements and QUIC-URB simulations for four different building layouts plus one case with an isolated tree. The correlation between URock and QUIC-URB is high, and URock reproduces the spatial variation of the wind speed observed in the wind tunnel experiments quite well, even in complex settings. However, sources of improvements, which are applicable for both URock and QUIC-URB, are highlighted. URock and QUIC-URB overestimate the wind speed downstream of the upwind edges of wide buildings and also downstream of isolated tree crowns. URock 2023a is available via the Urban Multiscale Environment Predictor (UMEP), a city-based climate service tool designed for researchers and service providers presented as a plug-in for QGIS. The model, data, and scripts used to write this paper can be freely accessed at https://doi.org/10.5281/zenodo.7681245 (Bernard, 2023).