LIC Case Study: Mt Mayon Volcanic Eruption

Question 1

Location/ Background

Answer 1

• Mt Mayon is a composite cone volcano
• The most active volcano in the Philippines
• Mayon is a result of the subduction of the Philippines Sea Plate beneath the Eurasian plate.
• Although in national park, the city of Legaspi is nearby along with several towns.

Question 2

Risk and vulnerability of the population

Answer 2

• Large ash emissions from Mt Mayon generally settle within a few km of the volcano and affect Legaspi, population of approx 200,000 people + large centre for tourism, education, health services, commerce and transport
• Ash emission settles in gullies, high risk of lahars
• Lava flows destroy local agriculture
• Nuees ardentes concentrated in gullies

Question 3

Activity prior to the eruption

Answer 3

• A brief seismic swarm in August 2016, then stayed quiet until a phreatic explosion on 13th Jan 2018.
• Growth of new lava dome

Question 4

Primary/ secondary hazards

Answer 4

• Heavy rain reported
• Mudslides
• Pyroclastic flows

Question 5

Economic effects

Answer 5

• US $3.4 million worth of damages to agriculture
• Flights in and out of Legaspi cancelled

Question 6

Social effects

Answer 6

• 10,000 people evacuated after 1st warning, then 40,000 people by 19th Jan
• Schools and colleges shut
• Some roads impassable by landslides and ash falls
• Nobody was killed

Question 7

Environmental effects

Answer 7

• Ashfall
• Rice, corn and abaca destroyed
• Ash column 5km high

Question 8

Political effects

Answer 8

Volcanic activity prompted responses from authorities

Question 9

Management:

Answer 9

• Evacuations, safety exclusion zones
• Monitored by Philippine Institute of Volcanology and Seismology
• 15 alerts published by SAFEY
• Filipino government committed US $1 million for a ‘cash for work’ programme as well as providing hygiene packages for 50,000 families for 10 days.
• Food packages to evacuees for 100 days
• Army called in to help
• Philippines Red Cross set up first and stations and welfare desks to provide psychosocial support
• US government committed over $100,000 used to distribute vouchers for families to buy essential items and hygiene kits -> constructed latrines, bathing cubicles and handwashing stations