Implementation of WRF-Hydro at two drainage basins in the region of Attica, Greece

Abstract. An integrated modeling approach for simulating flood events is presented in the current study. An advanced flood forecasting model, which is based on the coupling of hydrological and atmospheric components, was used for a twofold objective: first to investigate the potential of a coupled hydrometeorological model to be used for flood forecasting at two drainage basins in the area of Attica (Greece) and second to investigate the influence of the use of the coupled hydrometeorological model on the improvement of the precipitation forecast skill. For this reason, we used precipitation and hydrometric in-situ data for 7 events at two selected drainage regions of Attica. The simulations were carried out with WRF-Hydro model, which is an enhanced version of the Weather Research and Forecasting (WRF) model complemented with the feedback of terrestrial hydrology on the atmosphere, where surface and subsurface runoff were computed at a fine resolution grid of 95 m. Results showed that WRF-Hydro is capable to produce the observed discharge after the adequate calibration method at the studied basins. Besides, the WRF-Hydro has the tendency to slightly improve the simulated precipitation in comparison to the simulated precipitation produced the atmospheric only version of the model. These outcomes provide confidence that the model configuration is robust and, thus, can be used for flood research and operational forecasting purposes in the area of Attica.