An advanced workflow for simulating high resolution wind fields over complex urban terrain including single tree objects

Kurzfassung

Regarding urban environments, atmospheric models are often used to simulate processes, like i.e. heat island formation or the transportation of trace gases and particles, which are strongly connected to health and quality of living issues in modern cities. In the course of simulating atmospheric processes, wind speed and direction are often considered an important parameter. While freely available meteorological data provided by the national German Weather Service (DWD), as well as sparse in situ measurements are often used to feed atmospheric models of this kind, the low resolution (i.e. 1 km grid-size for DWD raster data) is not sufficient to represent small scale wind effects. Especially in urban environments effects like the amplification of wind in urban canyons acting as wind channels have a strong impact on how harmful air components spread. In order to model the transport of trace gases and particles in an urban environment with sufficient accuracy, higher resolution wind and pressure data is necessary. This paper presents a novel approach for the generation of high-resolution wind speed and atmospheric pressure field data on the basis of freely available geo data from different sources and the OpenFoam open-source computational fluid dynamics (CFD) framework which subsequently can be used as input parameters to improve the accuracy of atmospheric models.