Detecting the surface temperature anomaly of the Anak Krakatau Volcano using Landsat-8 TIRS during 2018 eruption

Abstract

Geologically, Indonesia is located at the confluence of tectonic plates which causes many active volcanoes to appear in these regions. The existence of these active volcanoes has a consequence that volcanic eruptions will always be a threat to residents who live in volcanic areas. Anak Krakatau volcano is one of the active and dangerous volcanoes located in the Sunda Strait. The volcano will always be a threat to residents who live in coastal areas around the Sunda Strait. With regard to the hazard, it is important to understand the characteristic of the volcanism of Anak Krakatau volcano, especially the physical symptoms that appeared before and during the eruption. This study analyzes the surface temperature anomaly of the peak area of Anak Krakatau volcano in the 2018 eruption. The Brightness Temperature (BT) were measured from channel-10 of Landsat-8 TIRS (Thermal Infra-Red Scanner) time series during 2018. Then, we analyzed the anomalies. The analysis results showed that in the case of Anak Krakatau volcano, a type of submarine volcano in Indonesia, the eruptions that happened during 2018 have demonstrated changes in the surface temperature of the peak area, spatially and temporally. Time-series analysis of brightness temperature data is useful for understanding when the volcano is in its normal active phase and when it is closing to the eruption. Spatial brightness temperature data analysis is useful for detecting the location of the eruption center and the direction of the lava distribution. So, Landsat-8 TIRS data is useful to detect the eruption precursors in Anak Krakatau volcano, a type of submarine volcano in Indonesia, based on the surface temperature changes and anomalies of the peak area derived from this image data.