Why only in Cebu? Mysterious haze explained

If the mysterious haze over Cebu last week came from Indonesia, why hasn't it been reported anywhere else? A scientist may have the answer.

For most of last week, residents of Cebu reported a strange grayish haze over the city—something of a minor mystery that has left many stumped. However, after running wind patterns through a comprehensive computer simulation, one scientist may finally have an explanation.

While air pollution is common in Cebu City—a bustling metropolis that is home to some four million people—last week's grayish skies were unusual enough to prompt numerous observers to comment on it online.

"We suspect that this haze is from Sumatra. It is unusually thick," noted PAGASA's Romeo Aguirre.

But why has it not been reported anywhere else in the country?

Since Indonesia's forest fires are southwest of the Philippines, it is curious that there were no reports of haze in places that lie in a path between Sumatra and Cebu.

"Nakakapagtaka nga na walang ibang report ng haze sa bandang Palawan o Zamboanga, o kahit man sa Negros o Panay," said GMA resident meteorologist Nathaniel "Mang Tani" Cruz.

However, atmospheric scientist Dr. Gerry Bagtasa may have an answer.

He had initially surmised the haze to be exclusively from local pollution, brought about by several factors including the interference of Tropical Storm Mujigae (then locally codenamed "Kabayan") with the usual movement of the southwest monsoon.

The interaction of all these factors helped create a sort of pocket of air above Cebu where pollution and other particles could accumulate into a visible haze.

But as it turns out, that was just part of the picture.

Bagtasa's careful analysis of satellite images showed that the haze from Indonesia fires did indeed reach the Philippines—across Visayas and Mindanao, in fact—but was too thin to be widely noticeable in most areas except Cebu.

"Due to the location of (Kabayan) and its slow northwest movement, it created a pathway for a couple of days for the haze to reach parts of the Philippines," he said.

"While most parts of the southern Philippines were covered by this relatively thin haze, reduction in visibility was exacerbated by local pollution emissions mainly in Metro Cebu and during a brief period Bacolod," he added.



— With a report from Agence France-Presse, GMA News