mprovement of Extreme Precipitation over South Korea in APHRODITE Data

Abstract

The APHRODITE (Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation of water resources) data has been widely used for the evaluation of the numerical model due to its higher spatial and temporal resolutions. However, some studies have indicated that it significantly underestimates the extreme precipitation values for several regions such as South Asia compared with station-based observation. In this study, therefore, the 25 year (1981-2005) APHRODITE precipitation data over South Korea during June to September was improved using Automated Synoptic Observing System (ASOS) data from Korea Meteorological Administration (KMA). After the spatial resolution and temporal interval of the ASOS data were changed to be same as those in the APHRODITE data, the GEV (Generalized Extreme Value) distribution for each data was calculated. After then, the GEV distribution of the APHRODITE data was corrected through the quantile mapping method with ASOS data. The corrected APHRODITE data was similar to the annual mean precipitation of the ASOS data. In particular, the corrected annual mean precipitation over South Korea reasonably increased by ~10% and the extreme value of precipitation have significantly improved compared to those from the original APHRODITE data.