By Dominique Gabriel G. Bañaga

The Philippine Institute of Volcanology and Seismology (Phivolcs) has downgraded the alert status on Mt. Kanlaon from Alert Level 2 to Alert Level 1.

Based on a Phivolcs bulletin yesterday morning, the decision to lower the alert level was based on four parameters.

They pointed out a significant drop in seismic activity, wherein they recorded low to baseline levels of zero to two volcanic quakes per day.

Recent ground deformation data also showed a continued inflation of the volcano’s edifice, which indicates the presence of pressurization under the surface; however, currently it has been moving at a significantly slow rate.

Phivolcs also noted a decline in sulfur dioxide (SO2) emissions.

According to the United States Geological Survey, SO2 emissions indicate magma is near the surface. Monitoring such emissions helps in determining the chances of an eruption. Although, in the case of Mt. Kanlaon, the relatively low levels of sulfur dioxide emission is indicative of a passive degassing from the hydrothermal system rather than stored magma beneath the volcano.

Visual observations by various Phivolcs observatories surrounding the volcano also witnessed weak to moderate steam-dominated degassing since December of 2017, which is consistent with a decline in hydrothermal activity.

Phivolcs said the volcano’s current state means they are not expecting any magmatic eruption, however, they are advising the public to still avoid entering the four-kilometer permanent danger zone.

The agency added, they will immediately inform the public if any new volcanic activity is observed./DGB, WDJ