Legazpi: The Philippine Institute of Volcanology and Seismology (Phivolcs) revealed on Tuesday that sulfur dioxide (SO2) emissions from Mayon Volcano have spiked to 7,115 tonnes per day, marking the second-highest level recorded since a decline in volcanic gas concentrations began on July 16.
According to Philippines News Agency, this latest SO2 measurement was derived from averaged data collected through stationary ultraviolet (UV) spectrometry. Since the volcano's status was downgraded to Alert Level 2, indicating a moderate level of unrest, on August 5, the average SO2 gas emission had been 3,844 tonnes per day. The recent increase is also accompanied by a slight rise in low-frequency volcanic earthquakes (LFVQs), which are linked to volcanic degassing.
Currently, the Mayon Volcano Network has recorded 12 LFVQs, although the real-time seismic energy release remains at background levels. Phivolcs has also detected short-term swelling or pressurization in the northern and eastern sectors of the volcano's edifice using measurements from electronic tilt deformation stations. The agency warned that this sudden rise in volcanic gas emissions could signal a potential shift towards renewed eruptive activity at the summit crater.
While Mayon remains under Alert Level 2, Phivolcs cautioned that there are possibilities of recurring eruptive unrest. The agency has urged the public to avoid the volcano's six-kilometer Permanent Danger Zone (PDZ) and advised communities and local government units within pyroclastic density current hazard zones to be ready for a possible escalation to Alert Level 3.
Moreover, Phivolcs has called for heightened alertness and preemptive measures against lahars and sediment-laden streamflows along channels draining the volcano, particularly during heavy or intense rainfall and in the event of a simultaneous explosive eruption. Civil aviation authorities are advised to continue warning pilots to steer clear of the volcano's summit, as ash and ballistic fragments from any sudden eruption could pose serious hazards to aircraft.
Phivolcs emphasized its ongoing close monitoring of Mayon Volcano and assured that updates on any significant developments will be provided.
