Inferences on the 2021 Ongoing Volcanic Unrest at Vulcano Island (Italy) through a Comprehensive Multidisciplinary Surveillance Network

In September 2021, the La Fossa crater at Vulcano, in Italy, entered a new phase of unrest. We discuss set monitoring parameters included INGV surveillance network, which closely tracked sequence effects related to crisis. The low-frequency local seismicity sharply increased, while GPS and tiltmeter networks recorded inflation cone, as an effect fluid expansion hydrothermal system. Gravity variations were probably fast processes within shallow sources. anomalies soil CO2 flux, fumarole temperature, plume SO2 flux marked strong increase vapor output from fumaroles. signs impending crisis had been evident chemical isotopic composition gases since July 2021. These geochemical clearly indicative enhanced input magmatic source. October, massive degassing also influenced areas base cone. some areas, thermal aquifer anomalies. By early November, reached its acme. Afterward, monitored started slow discontinuous decreasing trend although remaining, them, sensibly above background for several months. multidisciplinary approach proved decisive interpretation underlying acting different phases unrest, thus allowing consistent evaluation multiple hazards.