Climate change and the adaption to the effects are one of the biggest challenges especially for growing cities like Hamburg. More frequent heat waves, storms as well as air quality issues are only a few examples which require a detailed knowledge about urban climate and the wind within a city. Extensive measurement campaigns (http://www.uc2-3do.org) and high resolution simulations are performed within the BMBF funded research project [UC]2 “Urban Climate Under Change” to investigate the turbulent flow and wind gusts.
The large eddy simulation (LES) model PALM (www.palm-model.org) , developed by the Institute of Meteorology and Climatology (Leibniz University Hannover), is used to run the simulation on the DKRZ supercomputer. The model domain is located at the HafenCity Hamburg and includes an area of 1600 x 300 m with 600 m in the vertical. The spatial resolution is 1 m in all directions and the inflow wind speed is 5 m/s.
The animation shows the wind conditions respectively the vorticity around the HafenCity University building which is built directly on the waterfront of the Elbe river. The vorticity shown is a measure for the gustiness, which is highest at locations with reddish colours. The simulation depicts the high gustiness at the corners of the building and the entrance area. This issue is of special interest due to the metro exit located nearby. Furthermore, the long wake and influence of the building on the wind is clearly visible. The simulation illustrates the interaction of the flow with the surrounding buildings. Certainly, the model output has to be evaluated and compared with real measurement data to further improve the model and ensure realism. This analysis is done within the project [UC]2.
The sub-project TP10 "Meteorological characterization of forcing and urban response for climate model assessment”, realized by the Meteorological Institute of the Universität Hamburg, carried out several measurement campaigns at this exact site to provide high-resolution validation data.
For further information about the research project and available measurements, please have a look at: http://www.uc2-program.org/ and http://www.uc2-3do.org
Authors: Akio Hansen, Sarah Wiesner, Felix Ament (Uni. Hamburg), Katrin Scharf (Leibniz Uni. Hannover). Simulation performed by Akio Hansen (Uni. Hamburg), visualization rendered by Felicia Brisc (CEN/Uni. Hamburg).