PROPOSAL OF RAINFALL EVALUATION METHOD BASED ON COMPOUND PROBABILITY USED FOR METEOROLOGICAL ENSEMBLE DATA

Abstract

 In this study, we proposed a method to make a composite probability by using the total rainfall used in the hydraulic control plan and the cumulative rainfall in time that contributes to the peak discharge of the river. The rainfall probability was calculated using the rainfall data of the past experimental results of the meteorological enseble data “Database for Policy Decision-Making for Future Cliate Change”. The rainfall time that affects the peak discharge was set from the correlation coefficient between the peak discharge of the runoff calculation results using the past experimental results and the cumulative rainfall at each time(1hour to 72hour). We evaluated the rainfall with a compound probability and found the rainfall that caused flood damage with a higher probability of ozccurrence than the actual rainfall.