Explosive eruption at Etna volcano, Aviation Color Code raised to Red, Italy

Volcanic tremor at Mount Etna began increasing around 04:30 UTC on March 24, 2025, reaching high values by 07:00 UTC. The centroid of the tremor source was located in the area of the Southeast Crater, at an elevation between 2 900 m and 3 000 m (9 514 feet to 9 843 feet) above sea level.

The tremor remained elevated throughout the morning and stabilized at high levels by approximately 08:40 UTC.

Initially, infrasound activity was absent due to unfavorable weather, which impaired signal detection. However, modest infrasound signals were detected from around 08:30 UTC, gradually increasing in intensity over the next hour.

Ground deformation monitoring networks, including both clinometric and GNSS systems, reported no significant variations in recorded parameters during the same period. An exception was observed at the DRUV dilatometer station, which recorded a significant shift starting at 09:25 UTC.

Improved weather conditions over the summit later allowed visual confirmation of volcanic activity.

Surveillance cameras from the National Institute of Geophysics and Volcanology, Etna Observatory (INGV-OE) observed explosive events at the Southeast Crater beginning at 10:22 UTC, while forecast data showed the resulting eruptive plume dispersing northeast of the crater.

As a result of this activity, the Aviation Color Code was raised from Green to Yellow at 07:07 UTC, to Orange at 07:53 UTC, and ultimately to Red at 10:18 UTC, with strong strombolian activity observed and ash cloud moving NE.

Mount Etna is located above the city of Catania in Sicily, Italy, and has documented volcanic activity dating back to 1500 BCE. It is the highest and most voluminous volcano in Italy, composed mainly of basaltic lava flows. The Mongibello stratovolcano, formed during the late Pleistocene and Holocene over an older shield volcano, features the prominent Valle del Bove caldera, measuring 10 km by 5 km (6.2 miles by 3.1 miles).

Etna exhibits two main types of eruptions, often occurring together: frequent summit crater explosions with occasional minor lava flows, and less frequent but higher-effusion flank eruptions from fissures descending from near the summit.

Lava flows have historically extended to the base of the volcano and reached the sea on the southeast flank.

References:

¹ ETNA Volcanic Activity Report – INGV – March 24, 2025

² ETNA VONA – Etna Volcano Observatory – March 24, 2025

³ Etna Geological Summary – GVP – Accessed March 24, 2025