Weather Research and Forecasting (WRF) Model Validation of the Precipitation Climatology of the Sutlej and Beas River Basins, Northwest India

We investigate the skill of the Weather Research and Forecasting (WRF) model in reproducing the spatiotemporal characteristics of precipitation and maximum and minimum temperature for the Beas and Sutlej river basins, northwest India. Using a nested model setup, with 45 km, 15km and 5km horizontal resolution, the WRF model was run for 36 years (1980 – 2015) and validated against a network of 58 stations which record precipitation and 9 which record maximum and minimum temperature. The results indicate that the WRF model is able to realistically reproduce precipitation accumulation on a variety of temporal scales. Temperature is also well simulated, with only small biases for maximum and minimum temperature. We find that while there is a small dry bias in the WRF model, particularly at lower elevations, this bias is more extreme in the lower valleys of the Sutlej basin. This is partly a result of missing mountain-valley convergence in the early morning during the monsoon in the narrow valley of the lower Sutlej. Nevertheless, the model shows substantial skill for seasonal and diurnal precipitation. These findings demonstrate the benefit of this 36-year high-resolution climate simulation over current patchy and discontinuous in situ observations and global climate model and reanalysis datasets. The model clearly is able to simulate the complex interaction of topography and synoptic scale weather systems on precipitation and temperature in this region. The output of these simulations will be of great benefit to for hydrological modelling purposes to predict future water resources at the regional scale.