Estimating the Volcanic Ash Plume Course, PM_2.5 Emissions, and Environmental Impacts Based on the December 4, 2021, Mount Semeru Eruption

Abstract

Recently on the December 4, 2021 at 03:00 PM, 3676 m high Mount Semeru located in the East parts of Java Island has erupted. To our best knowledge, an immediate and rapid systematic analysis of the volcanic ash plume courses, PM2.5 emissions, and environmental impacts based on Mount Semeru eruption has not been implemented so far. Then, this research aims to provide and fill the research gap on the rapid assessment of recent Mount Semeru eruption. From the result, it is clearly visible that for 12 hours the volcanic ash plume course was eastward. The volcanic ash plume can travel a distance of 0–10 km to the North and South directions, and more than 10 km to the East direction. The size of the volcanic ash plume was large at 02:00 AM on December 5, 2021. The smallest size of a volcanic ash plume was recorded at 09:00 PM on December 4, 2021. Most parts of the ash plume (55.98%) or equals 39.01 km2 contain fallen volcanic material amounts ranged from 1 kg/m2 to 10 kg/m2. The fallen volcanic material amount peaked between 08:00 PM and 11:00 PM. Based on the estimation, the PM2.5 content in the atmosphere increased after the eruption. The mean of PM2.5 before the eruption was 48.5 ± 19.3(95%CI: 29.2 to 67.8 ug/m3). While after eruption the mean of PM2.5 was 79.4 ± 32.2(95%CI: 47.2 to112 ug/m3). It indicated that the Mount Semeru eruption has increased the PM2.5 equals 63.65%.

Geomorphological mapping and landform characterization of Semeru volcano after the eruption in 2021

“…Disaster activities of volcanic landscape areas are categorized as intensive disasters that cause big losses with a low frequency of occurrence. The primary disaster of a volcano is an eruption phenomenon consisting of lahar flows, ejection of pyroclastic material, and toxic gases and glowing clouds that can cover and change the land and cause loss of property and lives [1][2][3]. Slope and physiographic characteristics of the volcanic plains can also trigger secondary hazards after the eruption disaster in the form of lahar flows.…”