The Philippine Institute of Volcanology and Seismology (Phivolcs) clarified on Sunday, Aug. 15, that the poor visibility observed in some areas in northern and central Luzon was not caused by volcanic smog or "vog."
Science and Technology Undersecretary and Phivolcs OIC Dr. Renato Solidum Jr. said it is unlikely that this was caused by the eruption of the Fukutoku Okanoba submarine volcano in Japan.
"Dapat kung talagang sulfur dioxide ‘yan maaamoy nila ‘yung asupre (If it was really sulfur dioxide, it should smell of sulfur)," he said in a GMA interview.
"'Yung sa Japan hindi dapat sabihin na humahalo at nagkakaroon ng fog dahil sa volcanic eruption...plume na nasa mataas na kilometrahe ang lipad niyan mula sa ibaba (It cannot be said that there was fog because of the volcanic eruption in Japan. The plume stretching for several kilometers is from the ground up)," Solidum explained.
He said there are several factors that may have caused the fog.
"Dahil meteorologic dahil sa dagat sila magfa-fog. Pero kung volcanic smog ‘yan, ang kasalukuyan at kahapon na direksiyon ng sulfur dioxide ay papuntang western. Hindi tayo sigurado kung umabot diyan sa Zambales. Pero kung mababa lang talaga ‘yan ay dapat nalanghap nila ‘yan (It could be meteorologic. Because they are close to the sea, they could experience fog. But if that is volcanic smog, the current and previous direction of the sulfur dioxide was towards the west. We are not sure if it reached Zambales. But if the sulfur dioxide is present then they should have smelled and inhaled it," he added.
Vog is a type of air pollution caused by volcanoes.
Phivolcs said vog contains fine droplets of volcanic gas, such as sulfur dioxide, which is acidic and can cause eye, throat, and respiratory tract irritation in severities depending on the gas concentrations and durations of exposure.