Regional Rainfall-Induced Landslide Risk Assessment Using Susceptibility Mapping and Unexpected High-Intensity Rainfall

Landslides are one of the most common natural hazards in Malaysia, and besides geological conditions, rainfall intensity and duration are critical factors in assessing landslide risk. This study investigates the impact of daily rainfall variation on landslide susceptibility mapping and risk assessment. For this study, drainage, road, geological, and rainfall data were considered as key. The results show that rainfall significantly contributes to landslide risk increment by keeping geological and other triggering factors constant. Landslide vulnerability due to high-intensity rainfall was high on steep slopes causing high susceptibility compared to low-slope regions. The results also highlighted the relationship between triggering and geological factors in susceptibility assessment. Additionally, a comprehensive analysis through big data sets would help understand the spatio-temporal relationship between rainfall intensity and other landslide factors. Spatio-temporal data resolution will improve landslide susceptibility mapping and prediction accuracy to protect infrastructure and communities from potential landslide disasters in tropical climates.