Photo courtesy of Philippine News Agency (PNA).
Mayon Volcano recorded its highest sulfur dioxide (SO₂) emission level in 16 years, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
Phivolcs said in an advisory Friday that SO₂ emissions increased from 4,569 tonnes per day on July 9 to 7,475 tonnes per day on July 10, based on campaign spectrometry measurements.
The latest reading was higher than the 2,300 tonnes per day average recorded since the volcano’s current eruption began on Jan. 6, 2026. Mayon remained under Alert Level 3 due to continued volcanic unrest.
In its latest bulletin, Phivolcs reported ongoing lava flows along the Basud, Bonga, and Mi-isi gullies, as well as recorded volcanic earthquakes, rockfall events, and pyroclastic density current signals.
The agency also noted changes in ground deformation, indicating continued magma movement beneath the volcano, and reminded the public to stay away from the 6-kilometer Permanent Danger Zone due to possible volcanic hazards.