Future precipitation of Thailand according to a high-resolution multi-scenario regional climate modeling study

Abstract

A comprehensive high-resolution (20-km) simulation study was recently completed after 4 years of implementation. It deals with how Thailand's climate would change in the future in and around the mid 21st century years (2031-2070) with respect to the past 40-year ( 1961-2000) climate under three future emissions scenarios (SRES A2, A 1 B, and B 1) of the Intergovernmental Panel on Climate Change (IPCC)'s Fourth Assessment Report (AR4). A number of simulation experiments were conducted, downscaling global climate data to a regional scale with a fine horizontal resolution of 20 km using regional climate model RegCM3. The aim of this paper is to provide a synthesis of precipitation characteristics (in terms of means and extremes) and their potential changes in different regions of the country, based on the key findings obtained from the study. It was shown that a shift to drier conditions (i.e., less precipitation) was found over the Central-East and South sub-regions in every season under all three scenarios, with a larger degree in the latter (Fig. 1 ). In view of extremes, all sub-regions appears to have more consecutive dry days, while heavy precipitation and dry spells are expected to be intensified or to occur more often in the Central-East, North and Northeast sub- regions. These have an important implication in the agricultural and natural hazard contexts.