Fenech, S. (2014). M.Sc. Dissertation. Analysis of WRF Model Wind Parameters Sensitivity to Physics Parameterization Choice in the Central Mediterranean.
Supervisor: Dr N. Aquilina
This study analyses the effect of using different Planetary Boundary Layer (PBL) and Microphysics parameterizations, on modelled wind speed in the Central Mediterranean using the Weather Research and Forecasting (WRF) model. This region is surrounded by an number of orographic features thus making it a challenging region to simulate. Simulations were conducted using a two nested domain reaching a horizontal of 9.6 km x 9.6 km in summer (JJA) and winter (DJF) of 2011. Given that the study domain consists of a majority of water bodies, the effect of updating the Sea Surface Temperatures (SST) was also analysed.
A comparative analysis between modelled and observed data was carried out using hourly data at ten different station locations spread over the Central Mediterranean. Standard deviation (SD) and bias values of surface wind speeds indicate that the choice of physical parameterisations affects the performance of the WRF model during the different seasons. The PBL schemes have a dominant effect on the model performance for both seasons as opposed to the negligible sensitivity to change in microphysics parameterizations. The discrepancies between the different configurations were more prominent during winter than during summer. Upon updating the SST, the model behaviour was highly dependent on the location as well as the season. While results show a general over prediction when updating the SST for JJA, an improvement in results as compared to the simulations without the updated SST was noted for DJF.