Sandy beach erosion: impacts and adaptation strategies in Thailand

Abstract

AbstractThis paper focuses on sandy beach erosion as a result of rising sea levels, including adaptation option analysis in Thailand. Twenty-seven beaches in the provinces of Rayong, Nakhon Si Thammarat, and Trang were selected as study areas with high rates of erosion. The major scientific challenge entailed determining the relevance and contribution of rising sea levels (including storms) to beach erosion. The SimCLIM/CoastCLIM model was utilized to forecast changes in sea level and shoreline during the period of 1940–2100. A cost–benefit analysis (CBA) was conducted to evaluate adaptation options in terms of economics. The main outcome was a relevant contribution to knowledge on sea-level rise (including storm alteration) and its effects on sandy beach erosion, in terms of loss of sandy beach area and population migration. The results indicate that Mae Phim, Ban Ko Fai, and Pak Meng beaches are all threatened by erosion, and 8.02 and 23.26% of the erosion are attributed to storms and sea-level rise. Future scenarios (in 2100) showed 124.38 cm rise in 2100 sea level (compared to the 1995 baseline) leading to 507.90 m of eroded beaches, 2.15 km2 of sand loss and 873 people migrating. The results of CBA show that scenario 2 (beach nourishment) is not proper for application as an adaptation option on sandy beaches with high amounts of erosion (Ban Ko Fai and Pak Meng beach), while the option of beach nourishment alone is likely to be applied on Mae Phim beach due to its lower rate of erosion.