Quantitative precipitation estimation for an S-band weather radar using a dense gauge network

Weather radar provides areal rainfall information with very high temporal and spatial resolution. Radar data has been implemented in several hydrological applications despite the fact that the data suffers from varying sources of error. Several studies and technique have attempted to propose methods for solving these problems. Many different approaches for improving the quantitative accuracy of radar-based precipitation estimates are in use and under development. The best way to estimate rainfall properly is combining both radar and rain gauges data. Additionally, merging the radar estimate with precipitation observed by a dense rain gauge network seems to be a solution. The purpose of this study is to improve the accuracy of quantitative precipitation estimation using a dense network of precipitation gauges. S-band Doppler radar and 164 gauges comprising a dense network in the 35 x 28 km Seoul metropolitan basin are used. Average distance between gauges is about 2 km. We evaluate several techniques for merging radar and gauge observations for radar QPE. As a result, the errors in the rainfall estimation were reduced and the accuracy of quantitative precipitation estimation was improved.