The science behind the lightning coming from Taal’s column of ash

Lightning flashes from the ash plume spewed by Taal Volcano on Sunday, January 12, 2020. Photo courtesy of Domcar Calinawan Lagto

On Sunday, streaks of lightning flashed from the column of ash that spewed from Taal Volcano's phreatic eruption.

Domcar Calinawan Lagto, who photographed the phenomenon, observed that the thick ash cloud appeared to be "on fire."

The terrifying but magnificent sight was caused by electrically charged particles inside the ash column, according to UP Nationwide Operational Assessment of Hazards (NOAH) Executive Director Dr. Mahar Lagmay.

"When the particles get ejected [into the air], they rub against each other, causing friction so they get electrically charged. When the bonding between the negatively charged particles gets separated, there's lightning," he told GMA News Online in a phone interview.

He explained that the current produced when the charged particles separate caused bolts of lightning to emanate from the ash plume.

The concept is similar to how lightning is formed in regular clouds, which are made from water vapor, according to University of the Philippines (UP) environmental meteorologist Gerry Bagtasa.

"In clouds, ice particles hit one another and create the charge. That’s the similarity between the [two]," Bagtasa said in a text message to GMA News Online.

Taal Volcano's phreatic eruption on Sunday caused the evacuation of thousands of residents from nearby areas and the cancellation of flights to and from Metro Manila. Alert Level 4 has been issued over the volcano, meaning that a hazardous eruption is "imminent," or likely to happen in hours or days. — BM, GMA News