GIS application for building flood risk maps and assessing flood damage due to climate change in Dien Chau district, Nghe An province, Vietnam

Abstract This paper presents the results of applying GIS technology to build flood risk maps for a 100 cm sea level rise scenario in Dien Chau District, based on the climate change and sea level rise scenarios for Vietnam in 2020 by the Ministry of Natural Resources and Environment. It also performs multi-criteria analysis to assess flood impacts due to climate change, based on three groups of factors: exposure, sensitivity, and adaptive capacity. The research results showed that, with a 100 cm sea level rise scenario, Dien Chau District has an area of 2,525.123 ha at risk of flooding, accounting for 8.2% of the total area of the district. This district is divided into three levels of damage: (i) Low damage area, concentrated in the North, North-West, and a small part in the South-West, covering 4,511.98 ha, accounting for 14.7% of the total area of the district; (ii) Medium damage area, covering 15,107.02 ha, accounting for 49.22% of the total area, distributed around the center of the district and surrounding areas near the administrative boundary with Yen Thanh District; (iii) High damage area, concentrated around the district center and areas adjacent to the East Sea, covering 11,074.03 ha, accounting for 36.08% of the total area of the district. Additionally, the study proposes measures for each level of damage to mitigate the impacts of the factors causing flooding in the study area.