(File photo)

MANILA – An increase in volcanic sulfur dioxide (S02) emission has been observed again in the Taal Volcano, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported.

In an advisory late Sunday, Phivolcs said 17,147 tonnes of S02 emission was recorded on Aug. 7, higher than the 12,125 tonnes last Aug. 3.

The latest figure is also the highest gas emission since the volcano was placed under Alert Level 1 (low-level unrest) last July 11.

Airborne volcanic gas is forecast to drift east to west of Taal Volcano Island (TVI).

Increased degassing has been visible in the form of upwelling in the Main Crater Lake, and the voluminous steam-rich plume activity in the past six days.

On Monday, Phivolcs said three volcanic tremors that lasted 4 to 12 minutes, and a low-level background tremor, were recorded for the past 24 hours. Three volcanic tremors were also recorded in the previous 24-hour observation period.

These tremors were volcanic earthquakes signifying fluid or gas movement, Phivolcs Director Renato Solidum Jr. said earlier.

Moderate plume emission reaching 1,500 meters high was also observed in the past 24 hours.

Phivolcs reminded the public that Taal Volcano is still under Alert Level 1, which means sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall and expulsions of volcanic gas could threaten areas within TVI or Taal's permanent danger zone.

Local government units are likewise urged to continuously assess previously evacuated barangays around Taal Lake for damage and road accessibilities, and to strengthen preparedness, contingency and communication measures in case of renewed unrest.

Phivolcs added that aviation authorities must advise pilots to avoid flying close to the volcano, as airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircraft. (PNA)