Communities surrounding Taal Volcano in Batangas were warned against high levels of volcanic sulfur dioxide (SO2) which may lead to another eruption of the restive volcano.
In a bulletin issued on Saturday evening, July 3, the Philippine Institute of Volcanology and Seismology (Phivolcs) said Taal Volcano averaged 14,699 tonnes per day of SO2, the highest recorded SO2 in Taal.
The continuous upwelling in the main crater lake also generated steam plumes that rose 2.5 kilometers above the Taal Volcano Island.
"Elevated SO2 emission may be succeeded by eruptive activity at the Main Crater similar to increases in SO2 flux of 14,326 tonnes per day and 13,287 tonnes per day on June 28 and the morning of July 1, 2021, respectively, that preceded the short-lived phreatomagmatic eruption at 3:16 p.m. of July 1," Phivolcs said.
Moreover, Phivolcs said the increased SO2, coupled with the high relative humidity and wind velocity may trigger the formation of volcanic smog or vog over the lakeshore communities of Batangas.
Phivolcs reiterated that the current SO2 parameters indicate ongoing magmatic extrusion at the main crater that may lead to explosions.
Taal Volcano was placed under Alert Level 3 on July 1.
Phivolcs recommended the evacuation of residents in the Taal Volcano Island and high-risk barangays of Bilibinwang and Banyaga in Agoncillo town and Buso-buso, Gulod, and eastern Bugaan in Laurel town due to possible hazards of pyroclastic density currents and volcanic tsunami should stronger eruptions subsequently occur.
All activities on Taal Lake should not also be allowed at this time.
"Communities around the Taal Lake shores are advised to remain vigilant, take precautionary measures against possible airborne ash and vog and calmly prepare for possible evacuation should unrest intensify," Phivolcs said.
"Because of unprecedented high SO2 degassing from Taal main crater, local government units are additionally advised to conduct health checks on communities affected by vog to assess the severity of SO2 impacts on their constituents and to consider temporary evacuation of severely exposed residents to safer areas," it added.