Despite no recorded increase in monitored volcanic activities in Mayon, the Philippine Institute of Volcanology and Seismology (Phivolcs) on Friday raised its alert status from Level 1 (abnormal) to Level to 2 (increasing unrest).

“Magma has slowly ascended to the surface extruding lava that formed a lava dome. This time, the dome has increased in volume as more lava piled up,” Department of Science and Technology (DOST) Secretary Renato Solidum Jr. told the Philippine News Agency.

The sighting of the dome led to the upgrading of Mayon Volcano’s alert level from 0 to 1 last Aug. 21.

A slight inflation of Mayon Volcano has also been observed based on electronic tilt and GPS measurements and precise leveling survey. This indicated the continued slow ascent of magma to the surface. Hence, the alert level was raised to Level 2, Solidum said.

He, however, confirmed that Mayon Volcano’s seismicity has been low or none. Sulfur dioxide emission has been low, too.

“The presence of lava is an indication that magma has reached the surface, and it can precede an eruption,” Solidum said.

Phivolcs strongly advised the public to be vigilant and to refrain from entering the 6-kilometer radius permanent danger zone to avoid risks from sudden explosions, rockfall, and landslides.

In case of ashfall events that may affect communities downwind of Mayon’s crater, people should cover their nose and mouth with damp, clean cloth or dust mask.

Aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden eruption can be hazardous to aircraft, Phivolcs said. (PNA)