Crowd-sourcing data could help Philippines tackle deadly floods

Crowd-sourced data could help better predict the effects of the tropical storms and typhoons that regularly batter the Philippines and so save lives, disaster risk experts said.

When Super Typhoon Carina (international name Gaemi) hit the country in late July, Mahar Lagmay, head of the Nationwide Operational Assessment of Hazards (NOAH), requested people to submit photos of flooding in their area to contribute to the project's flood hazard models.

He said the reports would help test the accuracy of current models and correlate the amount of rain to the actual level of flooding and so help predict future flood hazards.

The Philippines is hit by around 20 large storms every year and, due to climate change, that is expected to only get worse.

"Typhoons will become more frequent and stronger, bringing in more rains.

When that happens, the floods will become bigger as well and become more frequent," said Lagmay.

Typhoon Gaemi killed 48 people in the Philippines and nearly 100 elsewhere in the region.

When the Taal Volcano, about 70 km (45 miles) south of central Manila, erupted in 2020 killing 39 people, NOAH, the country's primary disaster risk reduction and management program, asked people to report how thick the ash was in their neighborhood.

"A lot of people submitted. And because of those submissions, we were able to recreate the deposit footprint of the ash fall for the eruption," said Lagmay.

NOAH then calculated the volume, height, intensity and discharge rate from the volcano and used the data to predict the effect of future eruptions.

"When you have citizen engagement, it raises their stake at solving the problem.

Because there's ownership. They're part of the solution to the problem," said Lagmay.