The afternoon view from Doi Suthep and the world air-quality index at midnight on Tuesday show Chiang Mai's plight, as the 'Rose of the North' hit top of the scale as the worst polluted city in the world.
Forest fires have sent air quality in nine provinces to a level considered harmful to people's health, as cities in the North registered air quality that was among the world's worst.
The air quality index (AQI) in Chiang Mai as of 4am Tuesday stood at 230, compared with 170 in the Bangladesh capital Dhaka and 164 in Kabul, Afghanistan, according to Air Visual, an app that monitors air quality.
At midnight Tuesday, in slightly cooler night-time temperatures, Chiang Mai still was listed as the world's worst, with air quality in the high-danger zone for all residents but below 200 on the AQI scale.
Information from the Pollution Control Department (PCD) confirmed the haze in the North had reached worrying levels.
PM2.5 levels ranged from 70-124 microgrammes per cubic metre (µg/m³), exceeding the safety standard of 50 µg/m³ or lower.
Prime Minister Prayut Chan-o-cha is scheduled to visit Chiang Rai this Saturday, eight days before the national election.
Dr Rangsrit Kanjanavanit, a Chiang Mai resident who serves as a lecturer and cardiologist at the Faculty of Medicine at Chiang Mai University, said the smoggy skies show how the government's campaign to eradicate forest fires and open burning has failed.
Some of the haze has been attributed to neighbouring countries like Laos and Myanmar.
Critics say Thailand should work more with other governments to tackle the widespread practice of open burning.
Haze has been a seasonal problem in the North for over a decade. It usually appears from January to April but peaks in March as the extremely dry conditions increase the magnitude of forest fires.
This is compounded by farmers burning waste to clear land for the next harvest season.
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attribute to : to believe that something is the result of a particular situation, event, or person’s actions - ถือว่าเป็นของ
cardiologist : a doctor who studies the heart and deals with the diseases that affect it - แพทย์ผู้เชี่ยวชาญโรคหัวใจ
compound : to make a problem or difficult situation worse - เพิ่ม
eradicate : to get rid of completely or destroy something bad - กำจัดจนหมดสิ้น
harvest (noun): the activity of collecting a crop - การเก็บเกี่ยวผลผลิต
haze : water, smoke or dust in the air that makes it difficult to see clearly - หมอกควัน
magnitude : size or strength - ขนาดหรือ ความรุนแรง
peak (adj): to reach the highest amount or level, before becoming lower - ขึ้นจนถึงจุดสุดยอด, ช่วงเวลาที่หนาแน่นที่สุด
PM2.5 (n): atmospheric particulate matter (PM) with a diameter of less than 2.5 micrometres, which is about 3% the diameter of a human hair. It can lodge in the lungs and enter blood vessels, leading to respiratory and cardiovascular disease -
scale : a range of levels or numbers used for measuring something - ระบบการวัด
smog (noun): clouds of dirty and smokey air - หมอกควัน, ควัน, ควันพิษ,