This document summarizes a 30-year qualitative multi-hazard assessment conducted to determine coastal areas in the Philippines that are at high risk. The assessment characterized hazards based on historical data and estimated probability and impact to calculate risk potential at the provincial level. The study found that Aurora province has the highest overall risk potential among coastal provinces. It also identified several implications of the risks identified, including higher per capita costs in densely populated areas and risks for provinces with mismanaged forests or watersheds. Next steps suggested validating the results with a case study and using the risk information to devise concrete risk mitigation and communication strategies.

1. A 30-year Qualitative Multi-hazard Assessment
to Determine at-Risk Coastal Areas in the
Philippines
Pedcris M. Orencio1 and Masahiko Fujii2
1Graduate
2Faculty
School of Environmental Science, Hokkaido University, Japan, p.orencio@frontier.hokudai.ac.jp
of Environmental Earth Science, Hokkaido University, Japan

2. Natural Hazards
Natural events from physical or environmental processes
a. Plate movements
b. Sea surface temperature
Source: IRIS
Source: Sompotan 2007

3. Natural Disasters
2011 Worldwide Catastrophes
Source: Munich Reinsurance Co. 2011

4. Hazards and Disasters in the Philippines
Ranked as No.1 disaster-stricken country
in the world in 2009 by the Center for
Research and Epidemiology of Disasters
(CRED)
A total of 191 disasters, killed 903
persons, and affected more than 2.8M
families (Citizen’s Disaster and Response
Center)
Source: CDRC
Source: CDRC

5. In the Philippines, >80% are coastal provinces that
benefit from coastal resources
 60% of 87M population is in the
coastal areas (in 2005)
 Provides 43% of per capita protein
needs
 Employs 1M people in the coastal
rural areas
Very High
High
Moderate
Low
Very Low

6. Determining Disaster Risks
International Strategy for
Disaster Risk (ISDR)
Risk = Hazard x Vulnerability
International Union of
Geological Science (IUGS)
Risk = Probability x Impact

7. Use of EMDAT (1982-2011) in Risk Assessment
Source: EMDAT: OFDA/CRED- UCL

8. Hazard Characterization
A process that can be stand alone or part of a risk assessment
*
*Except for biological disaster events

9. Hazard Events at Provincial Scale
Provincial Hazard Event Score
(H) :
• Meteorological hazards affects most
• Climatological are prominent in the north
while, Hydrological are most common in
the south
• Geophysical and Biological are sparsely
distributed across the country

10. Probability Estimation
Probability (P) is the likelihood of
events occurring within a given
period of time
• Meteorological in most probable hazard in north
• Climatological in north and south
while, Hydrological only in the south
• Biological occur in contiguous urbanized areas
(i.e. GMA)
• Geophysical is the least probable among
hazards

11. Impact Estimation
Impact is consequence of the
events in the context of affected
human population
• Areas in the north have high cost
from Meteorological,
Climatological and Hydrological
hazards
• Areas that are impacted by
Geophysical are generally high
Reason?
Source: Yumul et al. 2011

12. Disaster Risk Potential at Provincial Scale
Provincial Risk Potential Score (RP)
:
Unit of Risk = per Capita Cost of Hazard
event for 30 year period
• Areas in the north are at high risk from Meteorological and
Climatological (though some areas in south are also at-risk from this
hazard)
• Areas in the south are at high risk from Hydrological
• There is less risk from Geophysical because of low probability of
occurrence

13. Provinces with Most Hazard Occurrences
Provinces
M
C
G
B
Metropolitan
Manila
Pangasinan
Ilocos Sur
Catanduanes
Davao del Norte
Davao Oriental
Albay
Sorsogon
Pampanga
South Cotabato
Combined (PH) :
M- Meteorological
C- Climatological
G- Geophysical
B- Biological
H- Hydrological
H
All

14. Provinces with Highest Hazard Risk Potential
Provinces
M
C
G
B
H
All
**Batanes
Aurora
**Catanduanes
**Camiguin
*Quirino
*Kalinga
Surigao del Sur
Compostela Valley
**Dinagat Islands
Zambales
Overall RP (ORP):
*Land-lock provinces **Coastal islands
M- Meteorological
C- Climatological
G- Geophysical
B- Biological
H- Hydrological

15. Risk Quadrant
High
Metro Manila
Pampanga
Albay
Leyte
Sorsogon
Cagayan
Tarlac
Isabela
Zambales
Quezon
Aurora
High
Low
Probability
Catanduanes
Compostela Valley
Low
Risk
Low
Kalinga
Quirino
Abra
Dinagat Islands
Impact
Mt. Province
Camiguin
Batanes
Biliran
High
Agusan del Norte
Agusan del Sur
Aklan
Antique
Eastern Samar
Lanao del Norte
Maguindanao
Marinduque
Misamis Occidental
Northern Samar
Romblon
Samar
Surigao del Norte
Surigao del Sur
Guimaras
Siquijor
Sulu

16. Implications of Risks
Per capita cost is higher in densely-populated areas

17. Implications of Risks
>80% of provinces at-risk have agricultural-based economy

18. Implications of Risks
Provinces with (mismanaged?) forest, forest reserves or watershed areas are more prone
to disasters

19. Summary and Next Steps
 Cost per capita could serve as indicator for individual response burden for
lack of government resources for disasters
 Aurora is the most at-risk coastal province in the Philippines based on a
multi-hazard risk assessment based on probability and impact of natural
hazard events
 Hazards are characterized based on individual scores of five key hazard
components taken from a 30-year information from International Disaster
Database (EMDAT of the CRED/OFDA/ UCL)
 Validation of results through a case study
• Amplification of risks from multiple hazards (e.g. disaster chains;
STORMS- LANDSLIDE- FLOODING - EPIDEMICS)
• Measure impacts in terms of implications on cost (i.e. recovery, loss
capital and economy)
 Devise risk communication strategies to achieve concrete risk mitigation
plans
• Importance of integration of risk in local planning cycle

20. “The view that disasters are temporary disruptions to be managed
only by humanitarian response, or that their impacts will be reduced by
technical interventions has been replaced by the recognition that they
are intimately linked with sustainable development activities in the social,
economic and environmental fields. So-called “natural disasters” are
increasingly regarded as one of the many risks that people face.”
UNISDR 2004
Thank you very much!
This presentation is supported by the Global COE Program, “Establishment of Center for Integrated Field
Environmental Science,” Ministry of Education, Culture, Science, Sports and Technology (MEXT), Japan.