The volcanic sulfur dioxide (SO2) emitted from Taal’s main crater on Sunday, Aug. 7, has exceeded 17,000 tons—the highest SO2 emission since the volcano’s alert status was lowered to Level 1 on July 11, said the Philippine Institute of Volcanology and Seismology (Phivolcs).

In its 11:30 p.m. advisory, Phivolcs said Taal Volcano had emitted 17,141 tons of SO2 on Sunday morning.

It pointed out that the average SO2 flux since July 15 was at 6,041 tons per day—higher than the average of 1,289 tons per day between May and mid-July 2022.

“Increased degassing has been visible in the form of upwelling in the main crater lake and voluminous steam-rich plume activity in the past three days,” Phivolcs said.

It warned of airborne volcanic gas that could be drifted to the general east to west of Taal Volcano Island, based on the air parcel trajectory data from the Philippine Atmospheric, Geophysical and Astronomical Services Administration.

In the past 24 hours, Taal Volcano also had three tremor events that lasted nine.

Phivolcs reminded the public that Alert Level 1 prevails over Taal Volcano, which means that it is still in abnormal condition and should not be interpreted to have ceased unrest nor ceased the threat of eruptive activity.

“Should an uptrend or pronounced change in monitored parameters forewarn of renewed unrest, the Alert Level may be raised back to Alert Level 2,” it said.

“Conversely, should there be a return of monitoring parameters to baseline levels after a sufficient observation period, the Alert Level will be further lowered to Alert Level 0,” it pointed out.

Under Alert Level 1, sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within the Taal Volcano Island (TVI).

“Phivolcs strongly recommends that entry into TVI, Taal’s permanent danger zone or PDZ, especially the vicinities of the main crater and the Daang Kastila fissure, must remain strictly prohibited,” it said.