Philippine typhoon intensified at pace beyond predictions

MANILA • The rapid intensification that turned this week's Typhoon Rai into the strongest storm to hit the Philippines this year surpassed all predictions, forecasters said, leaving nearly 400 people dead and almost a million displaced.

While it is unclear exactly how global warming is affecting the intensification of such storms, the United Nations' World Meteorological Organisation (WMO) has found it is "likely that the frequency of rapid intensification events has increased over the past four decades" as temperatures rise.

Before Typhoon Rai underwent a process of rapid intensification, forecasters at first warned of a storm that could bring considerable damage, with winds of up to 165kmh.

"But the situation evolved very fast," said Mr Nikos Penaranda, a forecaster who studies thunderstorms at the Philippines' national weather bureau. "Our models weren't able to predict the way the storm intensified, and it exceeded all our predictions."

In rapid intensification of storms, warm ocean water and differing wind speeds near the eye of the storm act as fuel to whip it up into a more severe event. In the case of Typhoon Rai, the storm turned into a Category 5 super typhoon, with speeds similar to when a passenger airplane starts to lift off the ground.

When it made landfall, winds of up to 210kmh were uprooting coconut trees, ripping down electricity poles, and hurling slabs of corrugated tin and wood through the air.

A lack of real-time data and case studies of similar storms in the region made it difficult for forecasters to predict just how much Typhoon Rai, or Odette as the storm is known locally, would intensify, said Mr Penaranda.

Ms Clare Nullis, a media officer specialising in climate change at the WMO, said: "The challenge in forecasting rapidly intensifying events is just that the speed with which this occurs, often in a matter of hours, leaves less time for disaster risk reduction mobilisation and evacuations."

Hurricane Ida, a Category 4 storm, experienced a similar intensification in the Gulf of Mexico hours before it slammed into the US state of Louisiana in August.

Ocean temperatures near the surface and at depths of up to 200m are rising around three times faster in this region than the global average, according to the WMO, making it fertile ground for more intense, less predictable storms.

In the past three decades, the Philippines has recorded at least 205 tropical cyclones, the highest of any Asian country, according to EM-DAT, a publicly available database on disasters run by the University of Louvain in Belgium.

Nearly every cyclone has taken lives and caused millions of dollars worth of damage. By comparison, China, the second-most affected country, has seen 139, and Bangladesh, also prone to storms, has seen 42.

REUTERS