The number of VLP seismic events (standard values 5-12) is high, 16.8 events/hour.

The amplitude of seismic tremor is high.

The infrasonic activity is high. The acoustic pressure of explosions is high, 2.9 bar (standard values <1 bar). The amplitude of puffing is medium, ~70 mbar.

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

Thermal activity of explosive events is medium. The number of thermal transients in the NE sector of the crater (standard = 100) is high, 523. The amplitude of thermal transients is low, 0.9 ºF. Exit velocity of pyroclasts, estimated through thermal camera analysis, is low, 16 m/s.

MODIS thermal anomalies are low: 3.71 MW (00:06 UTC yesterday).

Rockfall activity is low. The number of rockfalls is 4 per day.

SO₂ flux in the NE sector of the crater terrace is medium, 116 t/d

CO₂ flux based on the C/S of 18.73 mesured at 16:20 UTC on 2024/05/31 is high, 2173 t/d

Indice di Attività Vulcanica: high

• Seismic (VLP) rate HIGH
• Seismic tremor HIGH
• Puffing MEDIUM
• Acustic pression of explosions HIGH
• Thermal activity MEDIUM
• SO₂ flux MEDIUM
• CO₂ flux HIGH
• Rockfall activity LOW

The volcanic activity is generally characterized by strombolian explosions and puffing located at NE crater sector. In the last 24h, the Stromboli volcano showed a HIGH degassing activity (puffing with values of about 70 mbar). The pressure of the explosions is VERY HIGH (max acoustic pressure 2.9 bar). The number of thermal transients is HIGH, with LOW thermal amplitudes and LOW pyroclast exit velocities. The volcanic tremor shows HIGH values. The number of VLP events shows HIGH values (16.8 events/hour). MODIS/VIIRS images showed LOW thermal anomalies (max 3.7 MW). The SO2 flux measured at the NE crater sector is MEDIUM (116 t/d). The CO2 flux, based on the C/S ratio of 18.73 (measured on 31/05/2024 at 16:20 UTC) is HIGH (2173 t/d). The rockfall activity is LOW (4 events with LOW pseudo-volumes associated).The volcanic activity index is HIGH.