PHIVOLCS: Mt. Pinatubo now at zero alert level

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) on Thursday downgraded the alert status of Mt. Pinatubo to Alert Level 0.

In its daily bulletin, PHIVOLCS observed a continued decline in earthquake activity and a return to baseline seismic parameters in Pinatubo.

A total of 104 volcanic earthquakes or an average of two to three events per day with magnitudes ranging from 0.3 to 1.3 was recorded from July 1 to August 11.

“This is a significant decrease compared to the period from 28 January to 30 June 2021 when earthquake activity averaged 12-13 events/day and ranged in strength from ML 0.7 to ML3.2,” PHIVOLCS said.

The diffuse carbon dioxide flux from Mt. Pinatubo Crater lake, which is an indication of deep magma degassing, has also declined at 263 tonnes per day in mid-April 2021, it added.

PHIVOLCS said the number is well within the background range of less than 1,000 tonnes per day that were recorded since 2008.

It likewise reported that the ground deformation that was detected for the period of June 2020 to May 2021 is “likely” tectonic, rather than volcanic, in origin.

“In view of the above, PHIVOLCS-DOST is now lowering the alert status of Pinatubo Volcano from Alert Level 1 to Alert Level 0.  This means observational parameters have returned to baseline levels and the volcano has returned to a period of quiescence,” PHIVOLCS said.

However, PHIVOLCS said that the alert status may revert to Alert Level 1 in the event of a renewed increase in any one or combination of their monitoring parameters.

Individuals going to the Pinatubo crater were reminded to enter the vicinity with caution due to the perennial danger of rockfalls, landslides, and expulsions of lethal volcanic carbon dioxide.

“Furthermore, people living in valleys and active river channels are cautioned to remain vigilant against sediment-laden streamflows and lahars in the event of prolonged and heavy rainfall,” PHIVOLCS warned.

PHIVOLCS said today’s bulletin will be the last in the meantime, unless there are new developments in monitoring parameters.

It assured the public that PHIVOLCS will closely monitor the volcano’s condition, adding that new developments will be relayed to concerned agencies. —Hana Bordey/KBK, GMA News