Performance Comparison Between S-Band And C-Band Radar In Quantitative Precipitation Estimation

Meteorological radar has evolved into an indispensable instrument for monitoring precipitation and researching its correlation with hydrological response. Weather radar has often been employed to give precipitation inputs to flood forecasting operations for various river basins throughout the globe. The meteorological radar sends electromagnetic waves, which interact with raindrops and reflect a portion of the intercepted power. The frequency of the electromagnetic waves utilized depends on the application of the radar. In Malaysia, three types of common radar bands have been used to estimate the precipitation at various distances: S-band, C-band, and X-band radars. The difference lies in the wavelength of the emitted electromagnetic waves. The S-band radars have the longest wavelength, while the C-Band radars are typically designed for short wavelengths, although they may also be utilized for medium and long-range precipitation analysis. This study is to investigate the difference in performance of the S-band and C-band in quantitative precipitation estimates (QPE) based on point and mean rainfall analyses for two different case study river basins. The comparison between both radar bands shows that the C-band radar has a higher correlation between the radar QPE (indirectly estimated from the reflectivity) and gauge rainfall with higher R value. However, the study found that the radar QPE from C-band radar has larger error indicated by the higher discrepancy ratio as compared to the radar QPE from the S-band radar.