SO2 emission continues as Taal remains under Alert Level 3

FILE: Aerial shot of Taal Volcano on board a Philippine Air Force’s (PAF) UH-1 Huey helicopter on Tuesday (Jan. 21, 2020) during the PAF and Joint Task Force-Taal aerial reconnaissance at Taal Volcano. (PNA photo by Joey O. Razon)

MANILA — For the third time this week, sulfur dioxide (SO2) emission from the Taal Volcano was “below instrumental detection”, but the volcano remains under Alert Level 3.

The probability of sudden steam-driven and weak phreatomagmatic explosions, volcanic earthquakes, ashfall, and lethal volcanic gas expulsions in areas within Taal Volcano Island and nearby lake shores remains, according to the Philippine Institute of Volcanology and Seismology (Phivolcs) on Friday.

Phivolcs Monitoring and Eruption Prediction Division chief Mariton Bornas earlier explained that the drop in the SO2 emission could not be the only basis for authorities to lower Taal Volcano’s alert level status.

Bornas said before Phivolcs was able to record a low SO2 emission, there was a fluctuation in this factor, even reaching more than 5,000 average tons per day.

Taal Volcano has been under Alert Level 3 since January 26.

Meanwhile, for the past 24 hours, Phivolcs also observed moderate emission of white to dirty white plumes 500 meters to 700 meters tall.

Seven volcanic earthquakes with magnitudes 1.7 to 2.5 and with no felt intensities were also recorded.

The Taal Volcano Network, which can record small earthquakes, recorded two low-frequency events.

“These earthquakes signify magmatic activity beneath the Taal edifice that could lead to eruptive activity at the main crater,” Phivolcs said.

Phivolcs reiterated that entry to Taal Volcano Island, as well as areas over Taal Lake and communities west of the island within a 7-km. radius from the main crater must be strictly prohibited.

It added that aviation authorities must advise pilots to avoid flying close to the volcano, as airborne ash and ballistic fragments from explosions and wind-remobilized ash may pose hazards to aircraft.