A Quarter Century of MODVOLC Time-Averaged Discharge Rates: Assessing Four Largest Flank Eruptions on Mount Etna, and Selected Events on Other Basaltic Volcanoes

As volcanism may be considered synonymous with heat, the MODVOLC system utilizes thermal infrared satellite data from MODIS instruments to monitor the eruptive state of active volcanoes in near-real-time. This automatic hot-spot detection system is used here as the primary data source. We present a 25-year (2000–2024) record of MODVOLC lava discharge rates for Mount Etna in Sicily, Italy. Examples are given for four large flank eruptions occurring in 2001, 2002–2003, 2004–2005, and 2008–2009. Derived “lower” and “upper” erupted volume estimates for these eruptions range from 28−53×106 m3 to 57−104×106 m3 respectively. Such values correspond favorably to earlier estimates determined in the field or from other satellite data. Given the similarity of results, we then apply the same approach to the analysis of selected eruptions of five other basaltic volcanoes. Inversion of MODVOLC-derived time averaged discharge rates and volume data for Mount Etna eruptions in this study provides estimated magma chamber dimensions of ~2.2 to 2.6 km in radius for “lower” estimates (2.6 to 2.9 for “upper”), with an estimated total volume between ~45–74 km3 (“lower) and ~74–102 km3 (“upper”), which can inform plausible depth ranges at approximately 5 km when combined with petrologic/geodetic constraints.