LEGAZPI CITY, Philippines – With the onset of the rainy season, volcanologists here have again warned residents around Mt. Mayon to be on constant alert against potential lahar flows during heavy downpour.
Ed Laguerta, resident volcanologist of the Philippine Institute of Volcanology and Seismology (Phivolcs), said that since the volcanic materials on Mayon’s slopes remain unstable, heavy rains could still wash them down anytime and pose danger to communities at the foothills of the volcano.
“Based on our latest mapping, these loose volcanic debris are likely to pass through the same pathways and conduits as they did in the past lahar flows,” Laguerta said.
Phivolcs earlier estimated that at least 30 million to 50 million cubic meters of volcanic materials were ejected and deposited on Mayon’s slopes during the volcano’s month-long eruption episodes in December 2009.
Laguerta even confirmed that Mayon’s crater glow, though still within alert level 1, has turned more intense. Small explosions were also observed in the crater, threatening trekkers near the upper slopes.
Laguerta said they are installing new monitoring gadgets around Mayon, in coordination with the University of Singapore.
He said shelters are being built to house seismograph monitors and tiltmeters, which would detect Mayon’s tremors and ground deformation, respectively.
Meanwhile, Landrico Dalida Jr., Southern Luzon division chief of the Philippine Atmospheric, Geophysical and Astronomical Services Administration, said no inclement weather could be expected in the coming weeks as El Niño still prevails over the country.
In Albay, for example, Dalida said only 50 milliliters and 60 milliliters of rainfall was measured in May and June, respectively, way below the expected rainy month average of 170 milliliters.