The number of VLP seismic events (standard values 5-12) is medium, 11.3 events/hour.

The amplitude of seismic tremor is medium.

The infrasonic activity is medium. The acoustic pressure of explosions is low, 0.3 bar (standard values <1 bar). The amplitude of puffing is low, ~18 mbar.

Tiltmeters analysis does not show any significant deformation of the volcano edifice

Thermal activity of explosive events is not available. The number of thermal transients in the NE sector of the crater(standard = 100) is not available. The amplitude of thermal transients is not available. Exit velocity of pyroclasts, estimated through thermal camera analysis, is not available.

MODIS thermal anomalies are low: 1 MW (00:48 UTC yesterday).

Rockfall activity is medium. The number of rockfalls is 7 per day.

SO₂ flux in the NE sector of the crater terrace is medium, 72 t/d

CO₂ flux based on the C/S is not available

Indice di Attività Vulcanica: medium

• Seismic (VLP) rate MEDIUM
• Seismic tremor MEDIUM
• Puffing LOW
• Acustic pression of explosions LOW
• Thermal activity NOT AVAILABLE
• SO₂ flux MEDIUM
• CO₂ flux not available
• Rockfall activity MEDIUM

The volcanic activity is generally characterized by strombolian explosions located at the NE crater sector and degassing (puffing/spattering) located at NE, C and SW crater sectors. In the last 24h, the Stromboli volcano showed a MEDIUM degassing activity (puffing/spattering with values of about 18 mbar). The explosive activity is MEDIUM (max acoustic pressure 0.3 bar). The volcanic tremor shows MEDIUM values. The number of VLP events shows MEDIUM values (11.3 events/hour). MODIS/VIIRS thermal data shows LOW thermal anomalies (max 1 MW). SO2 flux shows MEDIUM values (last: 72 t/d recorded on the 21/04/2025), CO2 flux shows no new data (ultima misura: 946 t/giorno basate su un valore del rapporto C/S pari a 12.03 e misurato in data 19/04/2025). The rockfall activity is MEDIUM (n.7 events detected with LOW to MEDIUM pseudo-volumes associated). The volcanic activity index is MEDIUM.