Pemetaan Arah Aliran Lava Metode Lowest Height Dan Steepest Slope Menggunakan ALOS PALSAR dan ASTER GDEM V3 (Studi Kasus : Gunung Semeru, Jawa TImur)

Abstract

Mount Semeru experienced an eruption in December 2021, which caused many losses to the community and the environment. Because of this, disaster mitigation efforts are needed to reduce loss results. The form of disaster mitigation that can be done is to make a lava flow prediction map and recommendations for the distribution of the infrastructure needed. Based on previous research, flow data processing can be done using geospatial information system data. This study aims to predict the direction and extent of lava flows based on the Lowest Height and Steepest Slope methods and recommend the distribution of infrastructure in lava flow areas. The stages of processing research data using DEM ALOS PALSAR and ASTER GDEM V3, the value of DEM data correction, improvement of DEM (Fill Sinks) data, determination of prediction of flow direction and accumulation of flow, calculation of the area of the affected area and recommendations for infrastructure needs of lava flow areas. The results showed that lava flow predictions based on DEM ASTER GDEM V3 data using the Lowest Height method obtained the most significant percentage of flow area against the Mount Semeru KRB map in 2021. Flows are predicted to flow east, southeast, and south that hit 65 villages around Mount Semeru, with recommendations for planned infrastructure needs, namely Sabo DAM, DPT along lava flows, and Ring Net Barriers. The infrastructure is spread across 50 points around the Mount Semeru area.