Taal Volcano showing signs of pressure build-up, PHIVOLCS urges vigilance

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) on Tuesday urged the public to remain vigilant as signs of volcanic unrest continue at Taal Volcano, which remains under Alert Level 1.

Dr. Teresito Bacolcol, director of PHIVOLCS, confirmed in a Super Radyo dzBB interview that the volcano has been experiencing a continuous volcanic tremor for more than two days since July 6.

"Ang Taal Volcano ay nasa Alert Level 1 pa rin. For the past 24 hours, nakapagtala tayo ng isang volcanic tremor. Itong volcanic tremor na ito, since July 6 pa ito. More than two days nang tuloy-tuloy," he said.

(Taal Volcano remains under Alert Level 1. Over the past 24 hours, we've recorded a volcanic tremor. This has been ongoing since July 6—more than two days now.)

Bacolcol explained that this activity corresponds with a rise in real-time seismic amplitude measurement (RSAM), which was also the subject of a PHIVOLCS advisory earlier this week.

"Nung July 6, nagpalabas tayo ng advisory saying na tumataas ang real-time seismic amplitude measurement (RSAM) ng Taal," he said.

(On July 6, we issued an advisory saying that RSAM readings at Taal have been increasing.)

He added that RSAM reflects the amount of seismic energy being released, and a spike could mean that gas pathways inside the volcano are getting blocked—leading to a potential phreatic or phreatomagmatic eruption.

"Ang RSAM ang sukatan ng seismic energy release... Nangyayari ito kapag nabarahan ang daanan ng gas sa bulkan. Pwede itong magdulot ng biglang phreatic or minor phreatomagmatic eruption," he said.

(RSAM measures seismic energy release... This occurs when gas pathways in the volcano are blocked. It can lead to sudden phreatic or minor phreatomagmatic eruptions.)

While an eruption is not guaranteed, the possibility is increasing.

"Kapag nagkaroon ng pressurization, delikado 'yan... Hindi naman agad-agad sumasabog ang bulkan kapag mataas ang RSAM. Pero signal ito na may pressure build-up. We really have to be vigilant," said Bacolcol.

(When pressure builds up, it's dangerous... A high RSAM doesn't mean an eruption is immediate. But it's a sign that pressure is increasing. We really have to be vigilant.)

Bacolcol recalled the minor eruption on June 16, which spewed 250-meter high ash and affected only the inner volcano island. Whether a similar event could have wider impacts depends on weather conditions, particularly wind strength and plume height.

"Ang minor eruptions na nangyari sa atin last June 16, 250m lamang. So ang abo ay nasa Taal Volcano Island, hindi nga umabot ang abo sa paligid, around the communities. Depending pa rin kasi sa lakas ng hangin at kung gaano kataas ang plume natin," he said.

(The minor eruption on June 16 only reached 250 meters. The ash stayed on Taal Volcano Island and didn’t reach surrounding communities. It depends on wind strength and how high the plume rises.)

Missing sabungeros

When asked about ongoing efforts to locate missing sabungeros allegedly buried in Taal Lake, Bacolcol clarified that permission is not needed to search but entry to the island remains off-limits.

"Hindi naman kasi kailangan na magpaalam sa amin. Ang pinagbabawal naman natin, and again sa recommendation natin, huwag pumunta sa Taal Volcano Island."

(They don’t need to ask our permission. What we prohibit, as per our recommendation, is entering Taal Volcano Island.)

However, he said that activities in the lake surrounding the island remain safe under the current alert level.

"Sa lawa safe naman 'yan kasi Alert Level 1. Again PDC lang ang recommend natin huwag pasukin. Sa lawa walang problema. May mga fishermen nga d'yan at fish pens at may mga mangingisda. Walang problema."

(The lake is safe since we’re at Alert Level 1. We only advise against entering the Permanent Danger Zone. The lake itself is fine—there are even fishermen and fish pens there. No problem.)

Justice Secretary Jesus Crispin Remulla said Monday authorities are looking to start searching Taal Lake this week for the bodies of the missing sabungeros. —AOL, GMA Integrated News