The Philippine Institute of Volcanology and Seismology (Phivolcs) has observed three short-lived phreatomagmatic bursts at the Taal Volcano's main crater on Monday, Nov. 22.
In an advisory issued on Monday evening, Phivolcs said the phreatomagmatic bursts occurred at 8:11 a.m., 8:17 p.m., and 8:34 p.m., and lasted around one to five minutes, based on the seismic signals.
Phreatomagmatic burst occurs when hot magma comes into contact with groundwater.
"These events produced plumes 200 to 1,500 meters tall based on thermal camera monitoring. There have been six phreatomagmatic bursts since November 15 that are likely driven by fracturing and gas release from resting magma beneath the Taal Volcano Island (TVI)," the agency explained.
Phivolcs reminded the public that Taal Volcano remains under alert level 2, which means that the volcano continues to manifest "increased unrest."
The volcano has been under alert level 2 since July 23, 2021.
"Sudden steam- or gas-driven explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within and around TVI," Phivolcs warned.
It also reiterated that entry into the Taal Volcano Island, which is a permanent danger zone, especially the vicinities of the main crater and the Daang Kastila fissure, and extended stay on Taal Lake must be strictly prohibited.
Phivolcs advised local government officials to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest.