Work

Investigating Synoptic Influences on Tropospheric Volcanic Ash Dispersion from the 2015 Calbuco Eruption Using WRF-Chem Simulations and Satellite Data

Year: 2024

Type: article

Abstract: We used WRF-Chem to simulate ash transport from Chile’s Calbuco volcano eruptions on April 22 and 23, 2015. Massive ash and SO2 ejections reached the upper troposphere, and particulates were transported over South America, observed over Argentina, Uruguay, and Brazil via satellite and surface data. Simulations from April 22 to 27 covered eruptions and particle propagation. Chemical parameters utilized GOCART; meteorological conditions came from NCEP-FNL reanalysis. Two simulations (GCTS1 and GCTS2) differed in ash mass fraction in the finest bins (0–15.6 μm): 2.4% and 16.5%, respectively, to assess model efficiency in representing plume intensity and propagation. Analyzing active synoptic components revealed their impact on particle transport and the Andes’ role as a natural barrier. We evaluated and compared simulated aerosol optical depth (AOD) with VIIRS Deep Blue Level 3 data and SO2 data from Ozone Mapper and Profiler Suite (OMPS) limb profiler (LP), both sensors onboard the Suomi National Polar Partnership (NPP) spacecraft. The model successfully reproduced ash and SO2 transport, effectively representing influencing synoptic systems. Both simulations showed similar propagation patterns, with GCTS1 yielding better results. Comparison with VIIRS Brightness Temperature Difference data confirmed the model’s efficiency in representing particle transport. Overestimation of SO2 may stem from emission inputs. This study demonstrates WRF-Chem’s feasibility under volcanic configurations to reproduce ash and SO2 patterns enabling studies on aerosol-radiation and aerosol-cloud interactions and the understanding of atmospheric behavior following volcanic eruptions.

Source: Remote Sensing

DOI: 10.3390/rs16234455