PHIVOLCS raises alert level 4 over Mayon Volcano

This article has been updated to include statements from PHIVOLCS director Renato Solidum and updates on flights to the Bicol region.

Metro Manila (CNN Philippines, January 22) — Authorities on Monday raised the alert level over Mayon to below a notch of the highest warning of a dangerous eruption.

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) declared alert level 4 which warns of an imminent hazardous eruption — possibly within days. Level 5 means a hazardous eruption is taking place.

The National Disaster Risk Reduction and Management Council-Operations Center also raised a red alert status over the restless volcano.

PHIVOLCS reported "increased seismic unrest, lava fountaining, and summit explosions" in the area. The danger zone has been extended to eight kilometers from the previous seven.

PHIVOLCS director Renato Solidum warned of two possible scenarios in a press conference on Monday: continuous lava eruptions, or a more dangerous pyroclastic flow.

A pyroclastic flow is a mix of hot lava blocks, pumice, ash, and volcanic gas that moves at high speed down a volcano, according to the United States Geological Survey.

Solidum said this eruption was a possible "smaller version [of the] 2001 eruption," which had pyroclastic flow.

He also observed the plumes of smoke were mostly white, and could be attributed to water being mixed with the lava.

Solidum recounted that Mayon only had lava explosions in 2006 and 2009. A 2014 eruption also spewed out limited deposits. To date, the largest eruption has been in 1984, with the danger zone stretching to 11 kilometers.

He estimated that a possible pyroclastic flow would reach up to three kilometers in this eruption.

"The public is reminded to observe the danger zone — not to panic, but in essence just be ready. Prepare either gas masks, handkerchiefs or clothes to prevent inhalation of fine ash," said Solidum.

Albay Governor Al Francis Bichara first made the announcement on Facebook, calling the activity an eruption. Photos he posted showed clouds of ash rising from the volcano.

In a phone call with CNN Philippines, Bichara said there was zero visibility in the municipalities of Guinobatan and Camalig, as well as the city of Ligao in Albay.

The governor advised residents to stay at home and be alert.

"Everyone is advised to wear their facemasks and to stay indoors," Bichara added in another social media update.

Bichara also announced on Facebook guidelines on class suspensions for January 23.

He said classes in Legazpi, Daraga, Camalig, Guinobatan, Ligao, Oas, and Polangui were suspended until further notice.

However, class suspensions in the following areas were left up to the discretion of their respective mayors:

Rapu-Rapu

Manito

Jovellar

Pio Duran

Tiwi

Malilipot

Tabaco

Bacacay

Libon

Malinao

Sto. Domingo

"This kind of eruption is not over yet. Just like what we experienced a long time ago, it might extend up to a month," said Bichara. "Maybe tomorrow, there will no eruption, and the following day there will be [one]."

Legazpi airport temporarily closed

Legazpi airport temporarily closed airport operations effective 2:21 p.m. on Monday, Civil Aviation Authority of the Philippines Director General Jim Sydiongco announced.

PHIVOLCS also advised civil aviation authorities to make sure pilots avoid flying close to the summit, as the ash is hazardous to aircraft.

Local airline Cebu Pacific also advised the cancellation of flights bound for Legazpi and Naga City.

The affected travels include Flights DG 6204 (Cebu to Legazpi), DG 6205 (Legazpi to Cebu), 5J 327 (Manila to Legazpi), 5J 328 (Legazpi to Manila), DG 6117 (Manila to Naga), and DG 6118 (Naga to Manila).

Passengers flying to and from the two cities on Tuesday, January 23, are strongly advised to wait for further announcements, Cebu Pacific added.

PHIVOLCS seeks long term solutions

Solidum said that residents should start settling more than six kilometers away from Mayon, so they will not have to evacuate frequently during volcanic activity.

"Ang long term dapat na gagawin sa mga kababayan natin, walang nakatira sa permanent danger zone," he said.

[Translation: The long term solution our countrymen can adapt is, no one lives in the permanent danger zone.]

Activity from the restless volcano drove thousands of residents to evacuate last week. The new development at Mayon comes after Legazpi residents were allowed to return to their homes on Thursday.

Related: Legazpi residents allowed to go home amid Mayon Volcano unrest

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