Hazards - Pinatubo 1991 - Philippines Volcano CS

Question 1

Why do people live there?

Answer 1

• Limited choice -> island made of volcanoes
• Sacred territory ( tribes) - cultural
• No idea of risk
• Lush fertile soil - for farming
• Cheaper housing

Question 2

What type of volcano is it?

Answer 2

Stratovolcano

Question 3

What is the GDP per capita?

Answer 3

$9,750

Question 4

Where are they ranked on the HDI?

Answer 4

107th out of 189

Question 5

What were the features of the eruption?

Answer 5

• Ash cloud 40 km high - 2nd largest eruption
• Pumice ejected
• Avalanche of hot ash
• Gas
• Pyroclastic flows filled valleys with volcanic deposits 200m
• Rain + ash mixed - concrete mud
• Material so big collapsed to form caldera

Question 6

What were the short term impacts on people?

Answer 6

• 850,000 workers lost jobs
• 1.2 million lost homes
• Electricity went off, water contaminated
• Road links destroyed
• 75,000 people had to be evacuated
• Aeta tribe wouldn’t leave

Question 7

What were the long term impacts on people?

Answer 7

• $700 million in damages
• 847 people killed -> 300 collapsing roofs, 100 mud flow +lahars, diseases
• Most of Aeta died from disease

Question 8

What are the environmental impacts on the country?

Answer 8

• Farmland destroyed by falling ash -> unusable -> 1991 crops destroyed
• Global cooling caused by the ash in the atmosphere by 0.5 degrees celcius
• Fast flowing volcanic mudflows caused rivers to clog
• Reforestation activities set back
• 125 million pesos worth of seedlings lost

Question 9

What are the political impacts in the country?

Answer 9

• Return to pre-eruption conditions is impossible -> govt responses must create an attractive climate for new investment -> new livelihood growth away from lahars
• Threshold passed -> slowing development -> continued threat of lahars -> resources diverted to relief recovery and prevention

Question 10

What are the economic impacts?

Answer 10

• Nearly every bridge in Pinatubo destroyed -> several lowland towns were partially buried
• Heavy rainfall from typhoon Yunga -> building collapse
• Crops suffered ( 547 million pesos)
• Fisheries (165 million pesos)
• The USA air base -> washed by lahars

Question 11

What were the mitigation strategies against events?

Answer 11

• Monitoring included sulphur dioxide COSPEC and 7 tilt meter sites

Question 12

What was the mitigation against vulnerability?

Answer 12

• No existing hazard maps -> fasting prep of map showing previous eruption patterns + lahars and ash fall were mapped
• Short + long term aid from Red Cross + US
• Had to show people gruesome pictures

Question 13

What was the mitigation against losses?

Answer 13

• Successful monitoring of volcano by USGS and PHIVOLCS -> saved 500 lives and $ 250 million in property
• Pop of US base + cities = 250,000 -> daily briefings to communicate risks
• Evacuation plans in place -> 40km away from site -> 100% safe chosen