Flood Damage Map and Economic Loss Assessment by Google Earth Engine in Case of Rice in 2021 of Ayutthaya Province, Thailand

Abstract

The central region of Thailand is the most economical flow. Nevertheless, Ayutthaya Province has suffered from flood events annually. Near real-time flood mapping has potential for flood damage reduction measurement. This flood map is generated, using Google Earth Engine (GEE) Cloud-based by gathering the global surface imageries from Sentinel-1 synthetic aperture radar (SAR) by analyzing the pre- and post-flooded images, with land use dataset from MODIS and digital elevation model (DEM) from WWF's HydroSHEDS to determine the affected areas and to evaluate direct-damage of rice in term of economic loss. This research concentrates on the damage matters to rice only. In 2021, a storm named Dian-Mu was the worst that impacted the central region of Thailand. As a result, Ayutthaya flooded over 475,512.36 RAI, and we estimated rice would be lost 1.877 billion THB.