The study of possibility of extreme indices of Thailand under future climate change

Abstract

In the latest 20 years, it is clear that the climate change effected to water disaster of Thailand especially flood and drought. It occurred more frequency and severe then the past. Therefore the water management responding to future flood and drought is necessary to understand the impact of climate change to future extreme indices of Thailand. However the extreme indices from the global circulation model dataset differed depending on the assumption of the model, which the trend analysis was investigated from one model cannot be used identifying to be the representative of the trend of water disaster. The investigation of extreme rainfall indices was applied the possibility technique to analyze the trend of extreme rainfall. The objective of this study is to develop the possibility conjunctive with 10 indices for evaluating the extreme rainfall indices of Thailand which included consecutive dry days, consecutive wet days, number of heavy precipitation days, number of very heavy precipitation days, number of days above 40 mm, ratio of very wet days, maximum 1 day and 5 day precipitation amount, simple daily intensity index, and annual total wet day precipitation. The extreme indices which computed from daily observed rainfall data from Thai Meteorology Department and 5 CMIP6 global circulation model data included CESM2, MRI-ESM2-0, BCC-CSM2-MR, GFDL-ESM4, and CanESM.