Impact Trek 2019: Destination Philippines

Many of us in the catastrophe risk management industry actively help communities in need after natural disasters – through donations, working with organizations to promote resilience, or through on-the-ground assistance. Our intimate understanding of the power of these catastrophes makes us acutely aware of the need to act.

RMS and Build Change

Every year, a team of RMS employees and clients work together to help support our longstanding partner, Build Change, on how to ensure vulnerable communities benefit from safer housing, retrofitting and sound construction methods. The skills that both our employees and clients bring are very complementary to these tasks, and knowledge of risk modeling and analytics, and how to use this knowledge to develop resilience is highly valued.

Following successful visits to Haiti and Nepal in recent years, this year’s RMS Impact Trek visits the Philippines for the first time, with the team (including myself) on the ground in the country from March 17–25.

Build Change have been active in the Philippines since 2013. They have worked on a range of long-term projects from helping to rebuild schools, pre-disaster retrofitting of homes in poorer areas of Manila, through to training technicians in disaster-resistant construction skills in Guiuan in southeast Samar.

Choosing the Philippines

Impact of Typhoon Haiyan (Yolanda) in Tacloban, Philippines, taken on November 21, 2013. Image credit: DFID

According to the World Risk Index, the Philippines ranks as the third most disaster-prone country in the world. The southeast Asian country is deemed to have a “very high chance of natural disasters”, owing to its location within an area of high seismic activity, meaning future major earthquakes are likely, and the year-round threat of landfalling tropical cyclones.

RMS has two catastrophe models relevant to the country – the Philippines Typhoon and Inland Flood Model and Southeast Asia Earthquake Model, and it will be the first time that Impact Trek has visited a country with RMS cat risk model coverage.

Nationwide Earthquake Risk

With the Philippines located along the “Ring of Fire”, it is one of few countries in the world that has a high nationwide earthquake risk. Subduction zones and extensive crustal fault systems expose the country to a high risk of ground shaking, liquefaction, and landslide. And not only does the Philippines face significant earthquake risk, the building stock in the country is also particularly vulnerable to earthquakes.

The RMS Philippines Earthquake Model captures the complex interactions of multiple fault systems and sources of earthquake hazard in the Philippines and combines it with an understanding of the vulnerability of the building stock to capture the overall risk, and potential impacts of this tail-risk peril.

The most recent significant event was the 2013 Mw7.1 Bohol earthquake, the ground-shaking from which damaged thousands of homes, caused extensive landsliding and killed hundreds of people.

A scenario for a Mw7.2 earthquake on the West Valley Fault that is in close proximity to Manila would have devastating effects on the city and surrounding areas. This risk is compounded by the capital city Manila (Metro Manila pop. ~13 million), which is one of the most populous megacities in the world and has one of the fastest growing economies.

Frequent Typhoons

Approximately 20 tropical cyclones enter the Philippines Area of Responsibility (as defined by the Philippines Atmospheric, Geophysical and Astronomical Services Administration) each year, of which around eight go on to make landfall in the Philippines. Tropical cyclones can impact the Philippines at any time of year, but the most active time for tropical cyclone activity in the archipelago is between the months of July to September. Tropical cyclones generally approach the Philippines from the east, having tracked across the Philippine Sea, and cross the country in a westerly or north-westerly direction.

The highest risk regions include the Eastern Visayas, Bicol, and northern Luzon, with the more southerly and westerly islands experiencing less frequent and generally lower intensity storms. Due to its position within the western north Pacific basin, the Philippines is often the first significant landmass struck along a tropical cyclone’s track, and is frequently impacted by typhoons at their peak strength. Tropical cyclones bring a number of perils to the Philippines, including strong winds, heavy rainfall that can lead to flooding, and storm surge. The RMS Philippines Typhoon and Inland Flood Model captures the risk from these three perils, in addition to flooding from seasonal monsoon rains.

In 2018, the Philippines was impacted by two landfalling typhoons and three tropical storms. The most impactful of these events was Mangkhut (also known in the Philippines as Ompong). It was the strongest tropical cyclone to impact the country since Haiyan (Yolanda) in 2013 and the strongest to impact Luzon since Megi (2010).

The remote northeast of Luzon saw the most extensive devastation. According to Philippines’ National Disaster Risk Reduction and Management Council (NDRRMC), a total of 210,000 homes were damaged or destroyed. It is estimated that approximately 48,000 unreinforced or poorly constructed buildings were flattened, displacing more than 105,000 people.

Heavy rainfall from the typhoon, combined with the seasonal monsoon rains, led to localized flash and river flooding that triggered dozens of landslides. At least 127 people are known to have been killed with another 111 people unaccounted for several months after the event.

Follow the Trekkers

Myself and my fellow Impact Trek companions are really looking forward to gaining an understanding into the work that Build Change is doing in the Philippines, as it attempts to address this high-level of frequent nat cat threat together with buildings that are just not designed or built to cope. Follow us on our Trek with frequent updates on Twitter at Impact Trek and find out more about Build Change and their work in the Philippines.

James Cosgrove

Based in London, James works within Model Development as a member of the RMS Event Response team, supporting real-time Event Response operations and assisting on various Event Response projects. James holds a bachelor’s degree in Physical Geography and Geology from the University of Southampton and a master’s degree in Applied Meteorology from the University of Reading.

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