The Philippine Institute of Volcanology and Seismology on Tuesday warned the public that Taal Volcano in Batangas is still at alert level 1, “which means that it is at an abnormal condition.”
While there is no imminent magmatic eruption, the agency strongly advised the public to "refrain from entering the six-kilometer radius permanent danger zone due to the perennial life-threatening dangers of rockfalls, landslides/avalanches at the middle to upper slope, sudden ash puffs, and steam-driven or phreatic eruptions from the summit.”
Active stream or river channels and those identified as perennially lahar-prone areas on all sectors of the volcano should also be avoided, especially during extreme weather conditions when there is heavy and prolonged rainfall, it added.
The government will maintain its close monitoring of the volcano, and any new development will be communicated to all concerned stakeholders, the agency said.
Phivolcs said moderate emission of white steam-laden splumes that rose 250 meters before drifting to the east was observed as faint crater glow from the summit could be observed at night.
Sulfur dioxide (SO2) emission was last measured at an average of 371 tons a day on Feb. 12.
Ground deformation data from continuous GPS monitoring indicated that the edifice is still inflated relative to July 2019, Phivolcs said, despite a period of general deflation since July-August 2020, "and is undergoing short-term inflation since November 2020 except on the southwestern slope."
Deflation of the edifice with short-term inflation of the northwestern slopes since December 2020 has also been recorded by electronic tilt monitoring, it added.
The Batangas provincial government on Tuesday ordered the evacuation of residents on the island where Taal Volcano sits due to its "slightly increased" activity.
The Philippine Coast Guard said it was undertaking preemptive evacuation as a precautionary measure and had evacuated nearly 20 people so far— fewer than the initial number of residents targeted for evacuation.
"As of yesterday, before we had an emergency meeting, there was information that about 200 people [will be evacuated]. However, as we were checking [the island] this morning, it was less. Maybe, some voluntarily evacuated," PCG-Batangas chief Capt. Geronimo Tuvilla told Teleradyo.
The National Disaster Risk Reduction and Management Council said some 63 families or 200 individuals from Sitio Tabla and Sitio San Isidro in Talisay town were subject for the evacuation.
"Most of the residents have houses in the mainland. Others will be brought to the facility of the local government unit," it said in a statement.
Phivolcs advised that entry into the Taal Volcano Island, Taal’s Permanent Danger Zone or PDZ, especially the vicinities of the main crater and the Daang Kastila fissure, must remain strictly prohibited.
The Taal Volcano Network recorded 98 tremor episodes having durations of 5 to 12 minutes in the past 24 hours.
The volcano, which sits on an island surrounded by a lake in Batangas province, had a steam-driven eruption on Jan. 12, 2020, triggering an ash fall that reached parts of Metro Manila and nearby provinces.
The eruption displaced nearly 350,000 people in the provinces of Batangas, Quezon, Laguna and Cavite.
Taal Volcano is among 24 active volcanoes in the Philippines and has recorded 33 eruptions since 1572. Its worst eruption was in 1911 where some 1,335 people were killed, data from Phivolcs showed.