A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management

Thesis (M. Eng.) - Asian Institute of Technology, 2017

This study quantifies the climate change driven variations in longshore sediment transport along Thai coast as well as shoreline change in a specific location with river mouth jetties. The wave climate was obtained from 2 GCMs model which are ECHAM and GFDL climate model for present time slice (1981 to 2000) and future time slice (2041 to 2060). The longshore sediment transport rates were computed along 24 sandy beaches in the Gulf of Thailand for present and future time slice using CERC' s formula. Computation results show that climate change has different effects on changes in longshore sediment transport rates at each region of the gulf. Increasing gross and net longshore sediment transport are found in upper western gulf (region 2), and decreasing gross and net longshore sediment transport are found in lower westerngulf (region 1), upper gulf (region 3) and eastern gulf (region 4) for ECHAM wave climate, while GFDL wave climate provide increasing gross and net longshore sediment transport in lower western gulf (region 1) and some location upper gulf (region 3), and decreasing gross and net longshore sediment transport in upper western gulf (region 2) and eastern gulf (region 4). Moreover, shoreline change study at Cha-am Breakwater and GO-10k river mouth are studied to represent impact of climate change interaction with structures in upper and lower part of the Gulf of Thailand, respectively. Simulation results showed that climate change has slightly effect on future shoreline at Cha- am breakwater, while climate change has higher effect to drive shoreline change at GO-10k river mouth as a consequence of bigger incoming waves in lower part of the Gulf of Thailand.