การประเมินการเปลี่ยนแปลงมรสุมตะวันตกเฉียงใต้ในประเทศไทยด้วย แบบจำลองภูมิอากาศระดับภูมิภาคความละเอียดสูง

Abstract

A high resolution regional climate model developed by Meteorological Research Institute, Japan (MRI) called Non Hydrostatic Regional Climate Model (NHRCM) was used to evaluate precipitation and other parameters over Thailand during southwest monsoon season. Model configurations such as Bulk type microphysics, KF convective, MYNN3 PBL, radiation and land surface scheme were applied to simulate those climate parameters under the highest greenhouse gas emission scenario, RCP8.5. The experiments of this research were divided to two phases. The first one was to evaluate precipitation change during the period of June to September (JJAS) between the baseline period (1981 - 2000) and the future period (2080 - 2099). It was found that the precipitation in Thailand increases during the future period up to 100%. The second phase, 5-day cumulative precipitations and the average wind vector (pentad) were used to evaluate the southwest monsoon onset and monsoon active period. It shows that the average monsoon duration in the future is 1 pentad longer than its in the baseline. Furthermore, rain breaks during the monsoon season were also analysed. It is found that there is no significant change in rain breaks between baseline and future period.