Estimation of Storm-centered ARF Using Radar Rainfall by Duration and Return Periods

摘要

Design flood estimation, the application of the Areal Reduction Factor (ARF) is essential to convert the point rainfall to areal rainfall for the reference area. ARF calculation methods are largely divided into fixed-area method and storm-centered method. Since ARF is calculated by independent frequency analysis of maximum annual areal rainfall and point rainfall. On the other hand, storm-centered method is that make the maximum rainfall occur by spatial transition of each rainfall event to the center of the analysis watershed. Using the radar rainfall data, it is possible to calculate the real ARFs. In this study, the storm-centered ARFs were estimated by using radar data of the flood season (June to September) of 2007-2012 provided by Korea Meteorological Administration. Also, the center rainfall of the radar data were classified by the probability rainfall based on gauge rainfall data, and storm-centered ARFs were compared with fixed-area ARFs by duration and return period.