IDENTIFICATION OF FOREST AND LAND FIRE-AFFECTED AREAS USING SENTINEL-1A IMAGERY AND VIIRS HOTSPOTS: A CASE STUDY IN SILAUT DISTRICT, PESISIR SELATAN REGENCY

Abstract

Forest and land fires are ecological disasters that often occur in Indonesia, especially on Sumatra Island. This research aims to identify areas affected by forest and land fires in Silaut District, Pesisir Selatan Regency using Sentinel-1A imagery and hotspot data from VIIRS NOAA-20. The methods used in this research include SAR image preprocessing (Apply Orbit File, Speckle Filtering, Terrain Correction, and conversion data value from linear to dB), Radar Burned Difference (RBD) calculation, and area validation using VIIRS hotspot data distribution. Pre-fire imagery data was taken on May 20, 2023 and post-fire imagery data was taken on May 28, 2023. The processing results show that areas with RBD values < -3 dB have a significant decrease in backscatter and the area is assumed to be burned areas. Validation using hotspot data shows a strong spatial relationship between negative RBD values and hotspots, which is strengthens the interpretation of the results.