Chiang Mai is struggling with severe air pollution as wildfires continue to spread across several districts, with over 150 hotspots detected.
Wildfires continued to burn on Tuesday in mountainous areas in the northern province, with 150 active hotspots across 15 districts. The hardest-hit districts include Hot with 34 hotspots, Chiang Dao with 26 and Phrao with 23.
Thick smoke continued to blanket the city — the world’s third most polluted as of Tuesday morning — causing eye and throat irritation among residents.
IQAir said Chiang Mai had a PM2.5 fine dust concentration of 170 microgrammes per cubic metre (µg/m³), far above the safety threshold at 34.7 μg/m3.
Pollution levels remain dangerously high, prompting local authorities to activate fountains and use water-spraying vehicles along the old city moat to increase humidity and mitigate the haze, particularly in densely populated areas.
Data from the Climate Change Data Center at Chiang Mai University showed alarming PM2.5 levels in several areas on Tuesday morning. In Chiang Dao district, PM2.5 levels reached 240 µg/m³.
In Mae Hong Son, meanwhile, a blaze near Ban Mae Sa Pe Tai, a village in Khun Yuam district, had been brought under control, said Pornthep Charoensuebsakul, director of Protected Areas Regional Office 16.
The success was attributed to close cooperation between the office, the Region 3 Forest Fire Control Centre and the Royal Thai Air Force.
An air force BT-67 aircraft, guided by the forest fire control centre, conducted two flights on Monday, releasing 6,000 litres of water over the burning areas.
Ground support teams coordinated with pilots via radio, ensuring accurate water drops. Due to inaccessible terrain, aerial firefighting remains a crucial strategy in tackling wildfires in Mae Hong Son.
Ekkawit Meepian, the province’s governor, has integrated resources, including helicopters from the Ministry of Natural Resources and Environment and BT-67 aircraft from Phitsanulok, to combat the wildfires until the situation improves.
Despite the latest success, Mr Pornthep stressed the need for long-term cooperation between government agencies, private organisations and the public to prevent forest and agricultural burning and promote sustainable conservation efforts to safeguard northern Thailand from future pollution crises.
