Taal Volcano in Batangas remains under Alert Level 2 as it sustained its "increased unrest," the Philippine Institute of Volcanology and Seismology (Phivolcs) said on Wednesday, June 16.
The restive volcano had only one volcanic earthquake in the past 24 hours, but a low-level background tremor has persisted since April 8, 2021.
Phivolcs said the activity at Taal's main crater was dominated by the upwelling of hot volcanic fluids in its lake, which generated plumes one-kilometer high.
Sulfur dioxide emission also remains high at 4,821 tonnes per day on average, as recorded on Tuesday, June 15.
"Based on ground deformation parameters from electronic tilt, continuous GPS and InSAR monitoring, Taal Volcano Island has begun deflating in April 2021 while the Taal region continues to undergo very slow extension since 2020," it pointed out.
"These parameters indicate overall that magmatic unrest continues to occur at shallow depths beneath the edifice," it added.
Taal Volcano has been under Alert Level 2 since March 9, 2021.
Phivolcs reiterated that there remains a possibility of sudden steam- or gas-driven explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas that can occur and threaten areas within and around the Taal Volcano Island.
It said that entry into the volcano island, which is a permanent danger zone, especially the vicinities of the main crater and Daang Kastila fissure, should be strictly prohibited.