Phivolcs: Alert Level 4 remains despite Taal lull

MANILA, Philippines — Despite a lull in the “surface activity” of Taal Volcano, Alert Level 4 will remain as experts from the Philippine Institute of Volcanology and Seismology (Phivolcs) continue to evaluate developments.

“We are now also considering looking at the possibility that the volcano’s activity could have decreased, and if the alert level can indeed be lowered if there is lull for a long period,” said Ma. Antonia Bornas, chief of Phivolcs’ Volcano Monitoring and Eruption Prediction Division, at a press briefing yesterday.

“During a prolonged activity of the volcano –and it happens that there are lull moments – residents who earlier evacuated got restless and started going back to check on their homes. That is why we have this consideration of checking on the possibility if the alert level can be lowered,” she said.

Alert Level 4 remains in place as hazardous explosive eruption remains a possibility within hours or days. “However, to raise the alert level is not appropriate for the current situation,” Bornas said.

“At this stage, we are not discounting the possibility that a hazardous explosion of Taal Volcano could take place, though we are also looking on a possible lull of surface activity of the volcano for a long period,” she added. 

“Activity in the past 24 hours has generally waned to weak emission of steam-laden plumes 700 meters high that dispersed ash to the southwest,” Phivolcs bulletin read.

At the same time, Phivolcs said the amount of sulfur dioxide emitted by Taal Volcano has again increased. From higher-than-average 1,686 tons per day recorded on Jan. 14, sulfur dioxide emission was measured at an average of 4,186 tons per day the following day.

Bornas said the presence of this chemical compound in the atmosphere is an indicator of the magma’s movement.

She said they already had a calculation of the volume of magma inside the volcano before it erupted. But she added there is still a need to determine if there is continuous magmatic intrusion even after eruption.

The Philippine Seismic Network plotted a total of 566 volcanic earthquakes since Jan. 12. Between 5 a.m. Wednesday and 5 a.m. yesterday, 103 volcanic earthquakes were detected, 14 of which registered magnitudes one to four and were felt at Intensities I to III.

“Such intense seismic activity likely signifies continuous magmatic intrusion beneath the Taal edifice, which may lead to further eruptive activity,” Phivolcs said.  

Bornas said earthquakes and emission of sulfur dioxide are signs of ongoing activities underneath the volcano. Meanwhile, the Philippine Coast Guard conducted patrol along Taal’s coastline to assist in evacuation and relief as well as stop residents from fishing in the lake. –  With Janvic Mateo, Robertzon Ramirez

eismic Network plotted a total of 566 volcanic earthquakes since Jan. 12. Between 5 a.m. Wednesday and 5 a.m. yesterday, 103 volcanic earthquakes were detected, 14 of which registered magnitudes one to four and were felt at Intensities I to III.

“Such intense seismic activity likely signifies continuous magmatic intrusion beneath the Taal edifice, which may lead to further eruptive activity,” Phivolcs said.  

Bornas said earthquakes and emission of sulfur dioxide are signs of ongoing activities underneath the volcano. Meanwhile, the Philippine Coast Guard conducted patrol along Taal’s coastline to assist in evacuation and relief as well as stop residents from fishing in the lake. –  With Janvic Mateo, Robertzon Ramirez