The Reliability of X-Band Multiparameter Radar Rainfall Estimates

Abstract

Abstract Rainfall monitoring is an important activity for the development of a water-related disaster mitigation system. The rain gauge measurement is still regarded as the “ground truth”. To obtain the rainfall that represents an area, a high density of rain gauges network is needed. Besides, the installation of a large numbers of rain gauges is considered inefficient. The utilization of advanced technology is deemed necessary to complement the rainfall monitoring system, one of which is by using radar. Altough the radar rainfall estimates have a better spatial resolution, but the reliability needs to be evaluated. This study was carried out to evaluate the reliability of rainfall data from an X-Band Multiparameter radar by classifying the intensity of heavy rain and moderate rain. Then radar rainfall data was corrected using the Adjustment Factor (AF) method. The results show that the radar rainfall has better accuracy in predicting the moderate rain rather than the heavy rain. Furthermore, the X-Band MP radar has better accuracy when predicting rain in an area that has the elevation below the radar than the higher elevation area. Correction of the radar rainfall data using the AF factor produces a rainfall estimates which is closer to the ARR rain.