The Phillippine Institute of Volcanology and Seismology (Phivolcs) observed a phreatic, or steam-driven, eruption at the Taal Volcano’s main crater between 5:11 a.m. and 5:24 a.m. on Friday, April 12.

Based on IP camera images, Phivolcs said the eruption produced a white steam-laden plume, which reached 2,400 meters in height before drifting southwest.

“The phreatic event was likely driven by the continued emission of hot volcanic gases at the Taal Main Crater and could be succeeded by similar phreatic activity,” it warned.

However, it noted that background levels of volcanic earthquake activity and ground deformation detected in Taal suggest that the “unrest is unlikely to progress into a magmatic eruption.”

Alert Level 1 stays

Phivolcs explained that Taal Volcano remains on Alert Level 1, indicating that it is still in an abnormal state and should not be interpreted as having ceased unrest or the threat of eruptive activity.

“Sulfur dioxide (SO2) emission averaged 9,677 tons per day yesterday (April 11), and has been consistently elevated this year, averaging 10,248 tons per day since January 2024,” it said.

Phivolcs added that sudden steam-driven or phreatic explosions, volcanic earthquakes, small amounts of ashfall, and potentially fatal buildups or releases of volcanic gas are all potential threats to Taal Volcano Island (TVI) at Alert Level 1.

It also warned the public that the degassing of high concentrations of volcanic SO2 may pose long-term health risks to communities around Taal Caldera, which are frequently exposed to volcanic gas.

Permanent danger zone

Phivolcs reminded that entering TVI, Taal’s permanent danger zone, particularly near the Main Crater and the Daang Kastila fissure, is strictly prohibited.

“Local governments should continuously monitor and assess their communities’ preparedness, as well as implement appropriate response measures, to mitigate hazards posed by long-term degassing and related phreatic activity,” it said.

“Civil aviation authorities must advise pilots to avoid flying close to the volcano because airborne ash and ballistic fragments from sudden explosions, as well as wind-remobilized ash, can pose a threat to aircraft,” it added.