MANILA — The Philippine Institute of Volcanology and Seismology (Phivolcs) has expressed concerns over the escalating seismic activity at Bulusan Volcano in Sorsogon province.

Phivolcs Director Teresito “Toto” Bacolcol stated that if the current trend continues, there is a likelihood of raising the volcano’s alert status to Level 2.

The advisory, issued on Tuesday night, follows a notable increase in seismic activity over the past few days. As of December 29, 2023, the Bulusan Volcano Network (BVN) has recorded a total of 116 volcanic earthquakes.

Among these, 110 were identified as volcano-tectonic (VT) earthquakes linked to rock fracturing beneath the southern flanks, occurring at depths of two to six kilometers. Additionally, six low-frequency volcanic earthquakes (LFVQ) were recorded, associated with the movement of volcanic fluids.

Phivolcs Chief Bacolcol emphasized that ground deformation data points towards inflation or swelling of the southwestern and southeastern slopes. The institute remains vigilant, closely monitoring these parameters to determine whether an elevation to Alert Level 2 is warranted.

(El Amigo/MNM)

STO TOMAS City — A senior official from Phivolcs has advised the public to remain vigilant due to the possibility of volcanic smog, known as vog, making a return at any time.

This is as face-to-face classes at all levels have resumed in this city and surrounding local government units near Taal volcano, as it appears that the vog has subsided.

Nevertheless, Phivolcs Director Teresito Bacolcol emphasized the importance of staying alert for the potential reappearance of vog at Taal Volcano.

Even though the volcano had clear skies without vog since midday on Monday, he stressed the need for continued vigilance because vog could return.

He explained that the clear conditions were due to windy weather, which helped disperse the vog.

However, he cautioned that vog’s reappearance remains uncertain, influenced by factors such as wind speed, sulfur dioxide emissions, rainfall, and temperature.

Bacolcol also mentioned that vog would completely disappear when the surrounding area is free from haze and sulfuric odors.

Vog consists of fine droplets containing volcanic gases, particularly sulfur dioxide, and can linger when atmospheric layers prevent proper dispersion.

Exposure to vog can lead to irritation in the eyes, throat, and respiratory tract, with the severity depending on gas concentrations and the duration of exposure.

Taal Volcano is currently at Alert Level 1, indicating an abnormal condition with ongoing unrest and the potential for eruptive activity.

Access to Taal Volcano Island, especially the Main Crater and Daang Kastila fissures, remains restricted, and boating on Taal Lake is prohibited. (ai/mnm)

TAAL volcano is now clear of the smog caused by its emission of sulfur dioxide, which blanketed surrounding areas, forcing the suspension of work and classes on Friday, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).

“In Taal, it’s clear now unlike the low visibility yesterday. So now, the Taal volcano is visible from Batangas, so basically, there is no vog already,” Phivolcs Director Teresito “Toto” Bacolcol said in an interview with The Manila Times on Saturday.

The Calabarzon Region (Cavite, Laguna, Batangas, Rizal, and Quezon), especially near the Taal Lake area, has been covered by thick vog caused by the continuous emission of sulfur dioxide by Taal since early September.

Phivolcs said it measured a total of 4, 569 tons of volcanic sulfur dioxide per day as of Thursday, September 21 As of 5:30 a.m. on Saturday, however, the agency reported that the gas emission from the volcano decreased to 2, 730 tons per day.

Meanwhile, the same Phivolcs official also declared that the haziness in the air being experienced by Metro Manila residents as that coming from smog and not vog. (Amado Inigo/MNM)

MANILA — The head of the Philippine Institute of Volcanology and Seismology (Phivolcs) addressed concerns on Friday, emphasizing that the volcanic smog, or vog, resulting from gas emissions from Taal Volcano in Batangas since early September, is not a cause for alarm.

Teresito “Toto” Bacolcol, Director of Phivolcs, attributed the vog to “persistent sulfur dioxide (SO2) emissions,” which could be linked to the fact that “the volcano did not release gas when it erupted in 2020.”

Bacolcol stated that residents need not panic, as the volcano’s alert level remains at Level 1. He asserted, “It is not a cause for concern, and there is no indication that we should raise the alert status to Level 2.”

However, Bacolcol conceded that he couldn’t predict when the vog would cease. “As long as the volcano continues to emit gas in this manner, vog can be expected in the area,” he cautioned.

As a precaution, he urged residents to remain vigilant and wear masks when they detect the presence of vog to safeguard their health.

Bacolcol explained, “Continuous upwelling continues at Taal’s main crater lake, producing steam plumes that rise to 2,400 meters before drifting west-northwest.”

Although only five volcanic tremors were recorded in the past 24 hours, Phivolcs reported a total of 4,569 tons per day of SO2 gas emissions.

Vog is composed of fine droplets containing volcanic gases, such as acidic SO2, which can irritate the eyes, throat, and respiratory system. The severity of these effects depends on gas concentrations and duration of exposure.

Phivolcs noted, “People who may be particularly sensitive to vog include those with underlying health conditions such as asthma, lung disease, and heart disease, as well as the elderly, pregnant women, and children.”

Currently, Taal Volcano is under Alert Level 1, signifying an abnormal condition with ongoing unrest and the potential for eruptive activity.

Phivolcs stated, “If there is a significant increase or notable changes in monitored parameters indicating renewed unrest, the alert level may be raised to Alert Level 2.”

At Alert Level 1, there is a possibility of sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall, and the release of lethal volcanic gases, posing a threat to areas within the island. (ai/mnm)

Mayor Volcano (Photo courtesy of SCMP)

MANILA — Mayon Volcano, as reported by the Philippine Institute of Volcanology and Seismology (Phivolcs) on Friday, emitted plumes rising to a height of 2,500 meters from its summit crater.

During the past 24 hours, the volcano also experienced new occurrences of pyroclastic density currents (PDCs), increased instances of rockfall events, and volcanic earthquakes.

Phivolcs stated that Mayon Volcano remains at Alert Level 3, indicating a relatively high state of unrest as magma resides in the crater.

Compared to the previous day’s activity when plumes reached 1,000 meters, the current plumes were significantly higher.

Over the past 24 hours, there were a total of seven dome-collapse PDCs, 284 rockfall events, and two volcanic earthquakes recorded.

According to Phivolcs, there is a very slow release of lava from the summit crater, contributing to the formation of lava flows and the collapse of debris in the Mi-isi and Bonga gullies.

The lava flows in the Mi-isi (south) gully have extended to 2,230 meters, surpassing the 2,100 meters observed on Thursday.

Approximately 3,300 meters of collapsed debris were expelled from the crater. (AI/MTVN)