Kanlaon Volcano emits significantly high sulfur dioxide levels — Phivolcs


The Philippine Institute of Volcanology and Seismology (Phivolcs) said Kanlaon Volcano’s sulfur dioxide (SO2) emissions averaged 4,839 tons per day on Saturday, Aug. 10, marking the third highest level this year and the fourth highest since gas monitoring began.

In its advisory issued at 11:30 p.m. on Saturday, Phivolcs pointed out that Kanlaon Volcano’s sulfur dioxide emissions, which averaged 1,273 tons per day before the June 3 eruption, have surged to an average of 3,037 tons per day since then.

Volcanic earthquake activity has also persisted at an average of nine events per day since the eruption.

“The overall monitoring parameters indicate that magmatic processes beneath the volcano may be driving current unrest, causing persistently high concentrations of volcanic gas emission, swelling of the edifice, and occasional volcanic earthquake activity,” Phivolcs said.

It reminded the public that Alert Level 2 (increasing unrest) is still in effect, indicating that Kanlaon Volcano’s current unrest driven by shallow magmatic processes could lead to explosive eruptions or hazardous magmatic activity at the summit crater.

Phivolcs advised the public to remain vigilant and avoid entering the four-kilometer-radius permanent danger zone to minimize risks from volcanic hazards, including pyroclastic density currents, ballistic projectiles, and rockfalls.

In the event of ash fall affecting communities downwind of Kanlaon’s crater, people should cover their noses and mouths with a damp clean cloth or dust mask. 

Phivolcs also advised civil aviation authorities to instruct pilots to avoid flying near the volcano’s summit, as ash and ballistic fragments from a sudden eruption could be hazardous to aircraft. 

Likewise, communities living along river systems on the southern and western slopes—particularly those with a history of lahars and muddy streamflows—should take precautionary measures during heavy rainfall.