Scientists from the Istituto Nazionale di Geofisica e Vulcanologia in Italy have presented evidence that Mt. Etna was in an extreme state of overpressurization and was exhibiting signs of degassing in the months prior to erupting on Christmas Eve 2018. Using remote-sensing techniques the group measured gas output of the volcano and identified fluctuations in various gas ratios. They suggest this could indicate magma pressure buildup leading to an eruption.
Previous research has shown that ratios of gasses change as a volcano undergoes changes. Using sensors situated on and around the volcano, the researchers looked at ratios of sulfur dioxide, carbon dioxide, hydrochloric acid, and helium isotopes—gasses that have been associated with the buildup of magma in the volcano’s reservoir. The data gathered indicated that in the months leading up to the 2018 eruption, Mt Etna was emitting more carbon dioxide as well as showing variations in many other gas ratios.
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