Explosive activity, strong ash emissions observed at Etna volcano, Italy

The volcanic tremor amplitude at Etna volcano began increasing at 18:30 UTC on April 7, reaching high levels by 22:50 UTC.

The tremor’s source was located beneath the Southeast Crater at an altitude of approximately 2.9 km (1.8 miles) above sea level. Infrasonic activity also intensified from 23:00 UTC, localized at the same crater. Despite these signs of escalating activity, ground deformation monitoring networks, including GNSS and tiltmeters, did not record significant variations.​

Strong strombolian activity was observed at summit craters with weak ash emissions around midnight, prompting the Etna Volcano Observatory to raise the Aviation Color Code from Orange to Red.

The activity further increased with explosive activity and strong ash emissions by 04:18 UTC. The estimated volcanic cloud height was about 5.5 km (3.4 miles) from the top of the volcano, drifting southeast.

Explosive activity decreased over the next four hours, with weak ash emissions ongoing as of 08:11 UTC. The Aviation Color Code was lowered back to Orange.

Mount Etna is Italy’s highest and most voluminous volcano with a long documented history of activity dating back to 1500 BCE.

Etna’s most prominent morphological feature is the Valle del Bove — a 5 x 10 km (3.1 x 6.2 miles) caldera open to the east. The volcano exhibits two primary types of eruptions: persistent summit explosive activity and less frequent but more voluminous flank eruptions.

Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.

References:

¹ Comunicato Etna – INGV – April 8, 2025

² Mount Etna – VONA – INGV – April 8, 2025

³ Mount Etna Geological Summary – GVP – Accessed on April 8, 2025