PSEUDO OBSERVATION DATA CREATION METHOD FOR HYDROMETEOROLOGICAL FACTORS BASED ON REANALYSIS DATA

Abstract

 Reanalysis data has been used instead of observational data in the case of bias correction method is applied for outputs from GCM in an observational data scarce area, in which observational period is less than 20 years. However, reanalysis data does not match the real weather characteristics in a local scale since it is targeted at a global scale. In previous study, a statistical correction method for precipitation of reanalysis data has been developed. However, the method has not been applied for hydrometeorological data except for precipitation. Therefore, this study also developed and applied the method for the hydrometeorological data (temperature, humidity, pressure, shortwave radiation and wind speed). As a result, it is revealed that the distribution of corrected data by the statistical correction method is almost same relative to observational data. Furthermore, in order to increase the correction accuracy, it was found that we should apply probability distribution function (PDF) which is fitted the distribution of observational data according to the situation, since optimal PDF in the statistical correction method is different by the target station/area and/or hydrometeorological data.