The Philippine Institute of Volcanology and Seismology (Phivolcs) on Saturday, Aug. 13 said that Taal Volcano had generated six volcanic tremors and a 3,000-meter tall plume in the past 24 hours.

In its 8 a.m. bulletin, Phivolcs said the volcanic tremors lasted three to seven minutes.

Likewise, a 3,000-meter or 3-kilometer tall “voluminous” plume had emanated from Taal Volcano.

It was expected to drift north, northeast, and southwest of the volcano’s main crater.

Phivolcs said Taal’s sulfur dioxide or SO2 emission averaged 13,572 tons per day when it was last measured on Aug. 11.

The upwelling of hot volcanic fluids also continued, causing volcanic smog or “vog” over the Taal Volcano and neighboring communities.

Phivolcs said Taal Volcano remained under Alert Level 1, which means it was still in an 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.