Abrupt output increase of soil CO2 emissions from summit and peripheral areas of Vulcano Island 2021-2023

The Active cone of La Fossa caldera is a close conduit volcano affected by solphataric activity, manifested in the hot fluids released from fumaroles and the associated thermal anomalies in groundwater and exposed ground.The evaluation of the volcanic activity changes are inferred by the near real-time monitoring of soil CO2 fluxes diffused at the La Fossa Cone and the peripheral areas of Palizzi and Levante Bay and by the discontinuous monitoring of CO2 fluxes diffused by soil in areas around the CO2 continuous monitoring stations, La Fossa Cone, Palizzi and Levante Bay. In particular, from June 2021 to February 2023 we evaluated in near real time the level and duration of the exhaling crisis affecting the Island of Vulcano, by measuring the changes in mass and energy carried by the fluid release.The first summit volatiles increase degassing (VSCS station) started in June 2021 reaching in September 2021 the value of 34,000 g m2 d-1 more of one order of magnitude higher respect to the background values (1000 g m2 d-1).While, the first great increase of CO2 output in the peripheral area, measured with the soil CO2 survey, have been recorded at Levante Bay in May 2022 (17 t d-1) higher respect to the base values recorded in the past (2-4 t d-1). At November 2022 a new strong increase of soil CO2 degassing, have been estimated at Levante Bay area, reaching a values of 46 t d-1.The strong and deep input of volatiles released from the underlying magma batch strongly modified the chemical composition of the shallow plumbing system, bringing the system to a higher level of CO2 total pressure than the average background recorded in recent decades.