The Philippine Institute of Volcanology and Seismology (Phivolcs) observed an upwelling of hot volcanic fluids at the crater lake of Taal Volcano.

In its volcano bulletin issued on Thursday, May 13, Phivolcs said the upwelling monitored at the volcano’s crater lake generated 200-meter tall “weak” plumes that drifted to the southwest.

The agency has also recorded 43 volcanic earthquakes in Taal Volcano in the past 24 hours.

Of the number, 19 were low frequency volcanic earthquakes and 24 volcanic tremor events with durations between two to 12 minutes, as well as low-level background tremor that has persisted since April 8.

Phivolcs also measured a significant sulfur dioxide emission that averaged 5,179 tonnes/day on May 12, comparable to January, 13, 2020 when the volcano was still in eruption.

Ground deformation parameters continue to record a very slow and steady inflation and expansion of the Taal region that began after the January 2020 eruption.

“These parameters indicate persistent magmatic activity at shallow depths beneath the edifice,” the agency said.

Phivolcs said that Alert Level 2 or “Increased Unrest” has been maintained over Taal Volcano, “but elevated unrest has recurred in the past three days and volcano conditions remain unstable.”

It reminded the public that phreatic explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur under such alert level.

The agency has recommended prohibiting the entry into Taal Volcano island, its permanent danger zone, especially the vicinities of the Main Crater and the Daang Kastila fissure, as well as occupancy and boating on Taal Lake.