Phillpines case study

Question 1

assessment of management of hazards in the philliponies

Answer 1

The philippines socio-economic and political standing is a major challenge of hazard management:
Economic poverty of philippines means it often has to rely on international aid for recovery and relief from hazardous events.
Only 0.75% of the Philippines national budget is allocated to disaster prevention and relief.
BUT 5% of budgets are spent on disaster management at a sub-national level.
E.g Southern Leyte landslide relief efforts were underpinned by international aid. E.g $100, 000 of disaster equipment from the USA, 60 man search and rescue team from Malaysia, $1million from China in cash and material.

Philippines faces numerous political challenges; coup attempts, impeachment trials and corruption allegations. Hence this makes decision making relating to and enforcement of sustainable hazard management policy.

The shear number and frequency of natural hazards affecting the philippines:
e.g Bohol earthquake occurred three weeks before typhoon haitian. 10 cyclones a year….

Question 2

Philippine management of hurricanes and eval

Answer 2

Philippine Atmospheric, Geological and Astronomical Services Administration (PAGASA) monitor, forecast and predict atmospheric hazards.
6 hourly tropical cyclone warnings, thunderstorm alerts and storm surge warnings.
High wind and flood maps produced.
PAGASA identified the emergence of the typhoon haiyan days before it made landfall. It predicted its path, rainfall, flooding, landslides and storm surges. The highest alert level was issued for provinces along its path.

eval:
PAGASA did not reduce the impact of Typhoon Haiyan as they failed to convey the severity of the storm.
9 out of 29 respondents (31%) saying that they did not realise that their houses were located in potential storm surge areas, or assumed they were not.

Question 3

Philippine management of volcanoes and eval

Answer 3

Philippine Institute of Volcanology and Seismology (PHIVOLCS) monitors active volcanoes looking for signs of eruption:
Seismic tremors, steaming, ground swells, localised landslides..
It releases alert bulletins to communicate warnings to stakeholders who may be impacted, based on hazard maps produced from historical behaviours of volcanoes.

eval:
Successfully predicted eruption of mount pinatubo after 600 yers of dormancy due to steam explosions => 75,000 evacuated n 30km radius.
Despite forecasting and prediction strategies, they are not always successful at ameliorating the impacts of an event.

Question 4

Philippine management of earthquakes and evaluation

Answer 4

Philippine Institute of Volcanology and Seismology (PHIVOLCS) has 92 seismic stations releasing bulletins immediately after any tremor; shows location, magnitude, expected damage and expected aftershocks.
Maps of susceptibility to landslides and liquefaction.

evaluation:
Despite forecasting and prediction strategies, they are not always successful at ameliorating the impacts of an event.
It is possible to know where seismic activity is likely and study psat recurrence, IT IS IMPOSSIBLE to predict when a large magnitude earthquake will occur.
No prediction of 2013 Bohol Earthquake. Seismologists at PHIVOLCS had not known about the fault line transecting Bohol.

Question 5

Phillipines key facts:

Answer 5

population 103million, HDI = 0.688 ranking 115 out of 188.

20% of citizens live below the poverty line
1/7th of GDP from agriculture.

7000 islands. mean elevation 442m. on average 10 cyclones a year.

Question 6

Bohol Earthquake key facts

Answer 6

October 15th 2013
7.2 magnitude earthquake.
Focus = 12km
Epicentre located on Bohol Island.

Question 7

Bohol earthquake processes

Answer 7

Occurred along the Philippine fault zone, which is a complex system of fault lines that all contribute to the pressure created on each other. The Philippine, Eurasian and Sunda plates all contribute to this pressure.

This earthquake occurred on the East Bohol Fault, due to the build-up of friction and pressure from the plates moving towards each other that eventually released large amounts of energy as the plates slipped.

Question 8

Bohol earthquakes impacts

Answer 8

social:
222 people died, mainly due to falling rubble.

73,000 structures damaged, of which 14,500 destroyed.
32 bridges and 13 road sections were damaged or considered impassable, which prevented aid reaching certain areas.

$2.25billion USD worth of damage in Bohol and Cebu

Question 9

Bohol earthquake management

Answer 9

before:

The North Bohol Fault was not known about until after this event, so prevented extensive preparations.

After:

32 bridges and 13 road sections were damaged or considered impassable, which prevented aid reaching certain areas.

Question 10

Mount Pinatubo key facts

Answer 10

1991
Located in Central Luzon
A magnitude 7.8 earthquake on July 16th 1990, about 100 km northeast of Mount Pinatubo, seems to have triggered the volcano to wake from its dormancy: magma began to rise to the surface in March 1991.
The eruption was classified as size VEI 6.
5 cubic kilometres of material erupted on June 15th

Question 11

Mount pinatubo processes

Answer 11

Convergent plate boundary: subduction of the oceanic Philippine plate under the continental Eurasian plate. The oceanic plate was melted due to the subduction in the Benioff Zone, so was able to rise through the cracks and erupt as a volcano.
The earthquakes leading up to the eruption were caused by a build-up of friction and pressure, followed by a catastrophic slip that released large amounts of energy

Question 12

Mount pinatubo impacts

Answer 12

42,00 homes destroyed by ash and pumice
847 people died
300 people killed by collapsing roofs, due to ash and lahars

Estimated $450 million USD worth of damage

Question 13

Mount pinatubo management

Answer 13

Before:
Steam explosions and the smell of Sulphur made scientists monitor seismic activity, despite the volcano being dormant for 600 years.
75,000 people were evacuated in a 30km radius due to the predictions of eruption after seismometers were installed on April 3rd 1991

During:
A hazard map of predicted post-eruption lahars was drawn up, which allowed 200,000 people to be evacuated and saved an estimated 5000 lives

After:

The FEMA Recovery Continuum => eg civil engineers tried to isolate lahar sediment deposits that threatened to bury agricultural fields.
5 billion pesos spent to build dykes for lahars, although the channels became filled and were later destroyed by the lahars.

Question 14

Souther leyte mudslide key facts

Answer 14

A rockslide made of debris slid onto the village of guinsaugon
February 17th 2006

Question 15

southern leyte processes

Answer 15

Triggered by 684 mm of rain falling from 8th -19th February. This is 235% of the mean monthly rainfall. Destabilised the slope, by lubricating the slip plane and increasing weight of slope.
Triggered by earthquakes in Southern Leyte:
Philippine Institute of Volcanology and Seismology (PHILVOCS) recorded a 2.6 magnitude earthquake 21km west of Guinsaugon on Feb 17th

Question 16

Southern leyte impacts

Answer 16

Guinsaugon’s entire population (1,857 people) that were present at the time considered to have been buried except for 20 survivors found at the front edge of the debris field

15-20million m3 of material deposited
Approximately 45 hectares were covered in 25-40m of mud and rocks

Question 17

Southern Leyte management

Answer 17

before:
Limited management: there was no organised disaster risk reduction and management office in the municipality of Saint Bernard

During:
Relief teams including military personnel were sent into the area, but access was highly restricted due to the deep mud, boulders blocking railroads, washed out bridges and lack of heavy equipment

After:
Slow response to rehabilitation, with survivors remaining in evacuation centres for up to 6 months

Question 18

Typhoon haiyan key facts

Answer 18

Philippines has around 10 typhoons per year
A category 5 super typhoon
Wind speed of 230km/hr

Question 19

Typhoon haiyan processes

Answer 19

The Philippines is surrounded by seasonally warm ocean water of 27°c,
The Typhoons develop over the Pacific ocean and move westwards over the Philippines.

Over abstraction of water from the groundwater supplies in the Philippines has caused parts of the country to sink → thus creating a larger storm surge which caused more destruction than the strong winds alone.

Question 20

Typhoon haiyan impacts

Answer 20

7500 people were killed

5 to 6 meter storm surge

Question 21

Typhoon haiyan management

Answer 21

before:
There was limited knowledge about the potential risks amongst homeowners, with 9 out of 29 respondents (31%) saying that they did not realise that their houses were located in potential storm surge areas, or assumed they were not.
PAGASA identified the emergence of the typhoon haiyan days before it made landfall. It predicted its path, rainfall, flooding, landslides and storm surges. The highest alert level was issued for provinces along its path.

80,000 to evacuation centres such as schools and churches. But many brick and mortar structures were not strong enough to withstand the force of violent waves from the typhoon’s storm surge

The Bohol Earthquake only 3 weeks before meant that resources were already stretched thin, as the country was not set up to respond to multiple disasters despite its disaster-prone location