Analysis Of The Distribution Of Volcanic Ash From The Eruption Of Mount Merapi In 2010 Using Three-Dimensional Gaussian Plume Modeling And Hysplit (Hybrid Single-Particle Lagrangian Integrated Trajectory)

Abstract

The powerful 2010 eruption of Mount Merapi produced a widespread volcanic ash cloud with significant impacts, making a clear understanding of its dispersion pattern essential for disaster mitigation efforts. This study attempts to remodel this ash dispersion using two different approaches: the 3D Gaussian Plume and HYSPLIT models. The research aimed to analyze how eruption parameters and weather conditions influenced the ash's direction and spread, and to qualitatively compare the model outputs with MODIS Terra satellite imagery. To achieve this, the study processed volcanological data, such as column height and eruption volume, alongside meteorological data from ERA5 reanalysis for three key eruption phases: October 26, October 30, and November 5, 2010. The results show that the 3D Gaussian Plume model tended to produce an idealized dispersion pattern, spreading symmetrically from the peak with concentrations of 1.494E-03 kg/m³ (Oct 26), 4.395E-05 kg/m³ (Oct 30), and 0.0336 kg/m³ (Nov 5). In contrast, the HYSPLIT model provided more realistic results, depicting an elongated ash plume that followed the prevailing wind direction, with maximum mass load reaching 8.2 mg/m² (Oct 26), 0.1 mg/m² (Oct 30), and 110 mg/m² (Nov 5). The analysis confirms that the interplay between the eruption's characteristics (especially column height and emission rate) and meteorological conditions (wind speed) was the primary factor determining the ash's trajectory and reach. While both models accurately pinpointed the eruption's source, further validation was challenging as persistent cloud cover on the satellite images obscured the view of the ash plume.