Understanding Phuket’s ‘haze season’

Frédéric Pierson has been living in Phuket for 13 years, and the haze “phenomenon”, as officials like to call it, has been an annual event, with some years much more noticeable than others.

“It is not a natural phenomenon,” Frédéric says plainly. “It is from human causes.”

The smog is the result of human-caused pollutants, namely heavy burning in the north, along with all the usual air-polluting activities by humans, including vehicle emissions and factory pollution, he says.

The part that is natural, and which is the only part that Phuket officials are admitting, is that wind patterns and a weak northeast monsoon is what has left the haze smothering not only Phuket, but the whole region, for the past week.

“The area affected is larger than the island. It’s all over Southeast Asia, all over Thailand,” Frédéric says.

“The PM 2.5 readings were very high last week in Chiang Mai, Chiang Rai and Bangkok. The northeast monsoon that brings this to Phuket has been weak, while the weather has been very warm,” he adds.

“So the accumulation of the burn particles and smog cannot evacuate, and that is why we have had this heavy smog over Phuket. Last week there was no wind and all the [wind] patterns stayed the same, causing the pollution to stay in the same place,” Frédéric explains.

Frederick pointed to a report published by the Environmental Research Institute at Chulalongkorn University that he says is well documented and also explains very well how the “phenomenon” of warm weather and weak prevailing winds exacerbates the problem of air pollution to the extent that people see today.

The report, called “Stay Safe In the PM 2.5”, explains, “PM 2.5 level increase usually occurs during transition between winter to summer season. Approaching the end of winter, high pressure areas or a cold air mass spreads from China to Thailand, resulting in strong monsoons covering the Northeast part of Thailand.

“At this time, the upper part of Thailand will experience lower temperatures, ranging from cool to cold, and potentially very cold in some areas. However, this may not occur if high pressure covering the area becomes less, which in effect will reduce the northeast monsoon season to a calm wind.

“Temperature inversions in the lower parts of the atmosphere result in floating dust and distribution at a low level with poor air circulation and ventilation contributing to the accumulation of dust, smog and smoke in the atmosphere,” the report explains.

While that may explain why the PM 2.5 pollution is in higher concentrations during this time of year, the fact remains that the AQI (air quality index) for Phuket during the peak period over the past week has been four times the recommended maximum set by the World Health Organisation (WHO), Frédéric notes.

“In Europe, several days of PM 2.5 readings of 25-30 would automatically trigger health warnings. But not here… I am concerned when I cannot see the hills in Phuket Town from Saphan Hin, where I go for a run, and I can feel the rasp in my breath,” he adds.

The fact remains that it is pollution that is being trapped over Phuket by the wind, and there is very little people in Phuket can do about it as it is generated more than 1,000km from here.

“They know the problem. We all know what the causes of pollution are,” Frédéric says.

“The government  is not tackling the real issue. There are no real measures to reduce PM 2.5 and PM 10 particle pollution. They know what they need to do, but they are not doing it,” he concludes.