Tsunami hazard mapping and wave propagation analysis through numerical model simulations scenario: Case study Labuan Bajo, East Nusa Tenggara

¹ Marine Sciences and Technology Program, Faculty of Fisheries and Marine Sciences, IPB University, Bogor, Indonesia
² Research Center for Geological Disaster, National Research and Innovation Agency (BRIN), Bandung, Indonesia
³ Marine Geological Institute (MGI), Ministry of Energy and Mineral Resources, Bandung, Indonesia

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

Indonesia's topographical and tectonic configuration makes many coastal areas, including Labuan Bajo in East Nusa Tenggara, highly susceptible to tsunami threats. As a growing tourism center, Labuan Bajo necessitates comprehensive tsunami risk assessments to support disaster mitigation and coastal planning. This paper presents tsunami hazard mapping and wave propagation analysis through numerical simulations across six earthquake scenarios. The MIKE 21 Flow Model FM was utilized to predict tsunami wave dynamics, integrating high-resolution bathymetric data, earthquake mechanisms, and tidal fluctuations. Scenarios were based on potential rupture zones along the Flores Sea subduction area, illustrating both worst-case and moderate events. The models yielded estimates of wave height, arrival time, and tsunami energy at six coastal and nearshore observation stations. Results show considerable variation in wave heights, with peaks over 7 meters in severe cases. Arrival times ranged from 6 minutes to nearly 2 hours, indicating both near-field and far-field threats. Hazard maps highlight areas with high exposure, especially low-lying and densely populated zones. These findings underscore the necessity of incorporating numerical modeling into early warning systems, evacuation planning, and coastal infrastructure design. This study enhances understanding of tsunami hazards and provides recommendations to strengthen resilience in vulnerable, tourism-dependent coastal communities like Labuan Bajo.