The University of the Philippines (UP) Nationwide Operational Assessment of Hazards (NOAH) Center is the core component of the University of the Philippines (UP) Resilience Institute (UP RI). It generates a library of geo-hazard maps and aids in strengthening the teaching and research capacities of both public and private institutions. Aside from assisting educational institutions in formulating course offerings and educational materials in Climate Change Adaptation and Mitigation (CCAM) and Disaster Risk Reduction and Management (DRRM), UP NOAH Center conducts different forms of Information, Education, and Communication (IEC) campaigns and mainstreams vulnerability and risk assessment into local plans.
The Flood Modeling Component (FMC) is one of the four (4) components of the UP NOAH Center. It is responsible for creating high-resolution flood hazard maps. FMC uses a grid-based system to create two-dimensional (2-D) models that show overland flow in an area. Flood hazard maps can show different hazard levels categorized as low, medium, and high based on the danger the flooding may cause to people and structures. Each category also represents a specific range of depth and velocity. These maps can be utilized in creating DRRM-CCAM-related action plans, conducting hazard assessments, city and urban planning, and improving early warning systems to name a few.
Currently, FMC participates in research on multi-hazard assessments to gain a better understanding of the compounding effects of multiple hazards. This research is in collaboration with the UP Los Banos (UPLB) – Integrated Natural Resources and Environment Management (INREM) and some assistance from the Hazards Assessment Team (HAT), also one of the components under the UP NOAH center. As part of the continuous efforts of the UP RI – NOAH Center to further their research and development of their existing modeling and other technical processes, researchers are also looking to integrate the new data on the compounding effects of multiple hazards into disaster risk reduction and management and local capacity-building.
According to data obtained from the Emergency Events Database (EM-DAT)* of the Centre for Research on the Epidemiology of Disasters (CRED) and the World Health Organization (WHO), the Philippines had approximately 698 total recorded hazard events from 1900 to 2024 where 512 (73%) had only one hazard present and 186 (27%) occurred with the presence of multiple hazards. Despite the fewer number of documented multiple-hazard events, the cumulative impact on the economic damage of the multi-hazard events (approx. $27 billion USD) still costs more when compared to the value of the damages caused by the recorded individual hazards (approx. $24 billion USD). A similar pattern is observed when you look at the countries in the Southeast Asia (SEA) region, with fewer documented multi-hazard events. As it is, it manifested an even greater difference in the economic damage between documented individual hazards and multiple hazards. From 1900 to 2024, the total economic damage of all recorded hazard events approximately cost $339 billion USD where around $240 billion USD (71%) was due to multiple hazards and only about 98 billion USD (29%) was due to individual hazards.
To conduct the multi-hazard assessment, initial data on hazard validation is gathered through Focus Group Discussions and interviews. The data gathered is ranked and given a level of “importance” based on the frequency, regardless of severity, of a specific hazard in comparison to the presence or occurrence of other hazards. Simulations for different hazards in different scenarios are done to obtain the hazard data. The Flood hazard data comes from the simulations by FMC while HAT provides data on hazards such as Rain-induced Landslide, Debris Flow, and Liquefaction. Pyroclastic Flow data is obtained from the Philippine Institute of Volcanology and Seismology (PHIVOLCS). With the use of ArcMap, a GIS tool, the data range of the hazard levels was normalized by designating specific values that would correspond to Low, Moderate, and High on all four (4) hazards mentioned. The “Union” function will be used to overlay all hazard data and efficiently preserve all necessary attributes of each hazard for each location. Numerical values of 1, 3, and 5 will be used to represent the hazard levels on all Hazard maps consistently.
The ranking results will be used as input values to calculate the multi-hazard score which will be converted to Low, Moderate, and High based on the transformed descriptive hazard categories that would then show the overall magnitude. In short, results are expected to show the specific points where multiple hazards occur. GIS technology helps describe the existence and concurrencies of different hazards as well as their cumulative impact on the exposed area and their assets.
Studies that focus on single-hazard assessments are clearly necessary in the formulation of detailed mitigation measures but it is also important to acknowledge the data on multi-hazard events to create more effective risk reduction management plans. Currently, possible knowledge gaps pertaining to multi-hazard mapping exist because there are no standard methodologies and guidelines yet for creating multi-hazard models. UP RI – NOAH Center aims to spearhead the creation of a framework for multi-hazard mapping as this can be used as baseline information for planners and implementing bodies so that the plans will be more inclusive and even capable of mitigating the compounding impacts of multiple hazards.
REFERENCE:
* Public EM-DAT platform. (n.d.). https://public.emdat.be/data
PHOTOS:
World Bank Group. (2017). Project Highlights: Metro Manila Flood Management. In World Bank.
https://www.worldbank.org/en/country/philippines/brief/project-highlights-metro-manila-flood-management
Published Jun 9, 2016. (n.d.). Photos: Remembering the 1991 Mount Pinatubo eruption. SPOT.PH.
https://www.spot.ph/newsfeatures/the-latest-news-features/66626/mount-pinatubo-eruption-1991-20160609
Share, Twitter, Twitter, & Twitter. (n.d.). Kennon Road indefinitely closed to traffic. Www.pna.gov.ph.
https://www.pna.gov.ph/articles/1077357
Sunnexdesk, & Sunnexdesk. (2019, August 4). Landslide hits Kennon Road. SunStar Publishing Inc.
https://www.sunstar.com.ph/baguio/local-news/landslide-hits-kennon-road
Rodolfo, K. S., Lagmay, A. M. F., Eco, R. C., Herrero, T. M. L., Mendoza, J. E., Minimo, L. G., Santiago, J. T., Alconis-
Ayco, J., Colmenares, E. C., Sabado, J. J., & Serrado, R. W. (2019). Super Typhoon Bopha and the Mayo River Debris-
Flow disaster, Mindanao, Philippines, December 2012. In IntechOpen eBooks. https://doi.org/10.5772/intechopen.81669
Perez, Jeffrey & Amilbahar, Ranier & Baltazar, Hannah & Bon, Dexter & Buhay, Daniel Jose & Dizon, Margarita &
Grutas, Rhommel & Lamela, Ruben & Lamela, Melvin & Lasala, Melchor & Legaspi, Crystel & Llamas, Deo Carlo &
Marfito, Bryan & Mangahas-Flores, Robelyn & Peñarubia, Henremagne & Radam, Angela & Serrano, Andrew & Tañedo,
Cassidy & Tiglao, Robert & Ysulan, Azdine. (2020). Fault Geometry and Geologic Impacts of the 15 December 2019
Magnitude 6.9 Davao del Sur Earthquake. 10.5281/zenodo.10885398.