Numerical Weather Prediction for the Bulgarian Antarctic Base Area and Sensitivity to the SST Variable

Abstract

The weather forecast of good quality is essential for the humans living and operating in the Bulgarian Antarctic base (BAB), located on the Livingston Island coast at 62.64\(^\circ \) S and 60.36\(^\circ \) W. The numerical weather prediction models in southern high latitude regions still need improvement as the user community is limited, little test cases are documented and validation data are scarce. In this study, we suggest several ways to improve the local weather forecast model skill by modifications of the land cover and ocean temperature. We tested the sensitivity of the numerical weather prediction modelling system based on the Weather Research and Forecasting (WRF) model, configured for the BAB area, to the Sea surface temperature (SST) of the ocean around the island. The model configuration is described and details on the model performance are given. Several experiments with SST coming from different sources are performed, as well as experiments where the SST is scaled linearly. The conducted sensitivity experiments show that all of the considered meteorological variables are affected by the sea surface temperature, the most prominent differences being observed in the 2 m temperature field. With a uniform rise in SST, the corresponding tendencies are: an increase of the 2 m temperature, a decrease of the sea level pressure and an increase of the average wind speed. For the BAB region, the best results with unmodified SST data are obtained when using SST from the Copernicus Marine Service ocean model.KeywordsNumerical weather predictionAntarcticaSea surface temperature