By JEN BAYLON

The Philippine Institute of Volcanology and Seismology (Phivolcs) maintained Kanlaon Volcano’s status at Alert Level 3 (magmatic unrest) following a significant increase in seismic activity and volcanic gas emissions, signaling the possibility of short-lived explosive eruptions.

According to the advisory released at 1:30 p.m. yesterday, a total of 72 volcanic earthquakes were recorded by the Kanlaon Volcano Network between midnight and noon of the same day.

These earthquakes, ranging from magnitude 0.3 to 3.1, originated at shallow depths beneath the northern and northwestern flanks of the volcano.

Since Sunday, May 11, a total of 135 volcanic earthquakes have been detected, including strong volcano-tectonic events, which are typically caused by rock fracturing as magma or gas rises toward the surface.

Phivolcs reported that sulfur dioxide (SO2) gas emissions from the summit crater averaged 554 tons per day.

This is part of a declining trend in SO2 emissions, dropping from 4,144 tons per day in June 2024 to just over 2,100 tons per day as of April.

Experts warn that this decline, coupled with the increased seismicity, suggests a possible blockage of volcanic gas emission, which could lead to pressure build-up and swelling of the volcano — conditions that may precede a moderately explosive eruption.

Phivolcs strongly recommends that communities within a six-kilometer radius of the summit crater remain evacuated due to the risk of pyroclastic density currents, ballistic projectiles, ashfall, rockfall, and other volcanic hazards.

Local government units are urged to prepare for possible further evacuations should the situation escalate.

The advisory also calls for increased vigilance against potential lahar flows and sediment-laden streams, especially during heavy rains, and advises civil aviation authorities to warn pilots against flying near the volcano’s summit due to the risk of sudden explosive eruptions./JB, WDJ