Phivolcs logs high sulfur dioxide emission at Taal Volcano, public warned against 'vog'

Published August 19, 2021, 5:24 PM

by Jhon Aldrin Casinas

High levels of sulfur dioxide emission was recorded at Taal Volcano in Batangas on Thursday, Aug. 19, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.

The main crater of the Taal Volcano is seen during an aerial survey done by government officials, more than a week after the eruption of Taal Volcano in Batangas. (Mark Balmores / MANILA BULLETIN / FILE PHOTO)

Phivolcs said that the first measurement of volcanic sulfur dioxide or SO2 flux from Taal’s main crater totaled 15,347 tonnes/day on Thursday.

“This marks a rising trend in volcanic SO2 degassing since August 13, with the short-term average from then until present measured at 8,351 tonnes/day,” the agency said in an advisory.

In the same period, tall steam-rich plumes that rose 1,000 to 3,000 meters were also generated by the volcano’s main crater.

“The high SO2 flux, water vapor emitted in plumes, weak air movement and solar radiation will continue to produce volcanic smog or vog over the Taal region,” Phivolcs said.

The agency said it has received reports of adverse effects on some residents of Talisay and Brgy. Barigon, Agoncillo. Hazy conditions were also observed over Taal Lake and its surrounding areas.

State volcanologists explained that vog consists of fine droplets containing volcanic gas such as SO2 which is acidic and can cause irritation of the eyes, throat and respiratory tract in severities depending on the gas concentrations and durations of exposure.

People that are particularly sensitive to such ill effects are those with health conditions such as asthma, lung disease and heart disease, the elderly, pregnant women and children.

As this developed, Phivolcs has urged the public to avoid outdoor activities, stay indoors and shut doors and windows to block out vog.

“Protect yourself. Cover nose, ideally with an N95 face mask. Drink plenty of water to reduce any throat irritation or constriction,” it said.

“If belonging to the particularly sensitive group of people above, watch over yourself and seek help from a doctor or the barangay health unit if needed. If serious effects are experienced, call the doctor or the barangay health unit,” it added.

Amid the rise in SO2 emission, the agency recommended that local officials should conduct health checks on communities affected by vog to assess the severity of SO2 impacts on their constituents and to consider temporary evacuation of severely exposed residents to safer areas.

Local government units were also advised to regularly check the weather and wind forecasts to assess potential exposure of their constituents so long as SO2 emission remains elevated.

It also urged authorities to monitor activities of aquaculture workers to ensure that no one ventures too closely to Taal Volcano Island (TVI) and gets exposed to lethal concentrations of volcanic SO2.

Phivolcs reminded the public that Taal Volcano remains under Alert Level 2 or “Increased Unrest”, which means that the threat of sudden steam- or gas-driven explosions and lethal accumulations or expulsions of volcanic gas can occur.

“Increasing SO2 flux may also forewarn of potential phreatomagmatic activity similar to the 1 July 2021 eruption,” it noted.

“Venturing into TVI must therefore remain strictly prohibited, and LGUs are advised to continually check on the preparedness of their constituent communities,” it added.