My fellow human beings don’t seem to have enough common sense to refrain from setting alight thousands of fires in the forests and fields of Northern Thailand each dry season. Every year, around March, the skies over Chiang Mai turn into a thick, choking smog—leaving the citizens with burning eyes, sore throats, chest pain, and asthma. The toxic particles in the air become too much for some of the elderly and newborn babies, and undoubtedly a number of premature deaths occur each year.
The people are unable to act in their own best interests, but fortunately there are wise, air-born beings who look down with benevolence—compassionate guardians of the world who decided this year to take pity on the foolish humans.
Now, you may not believe in devas or nagas, living in the clouds, controlling the atmosphere. But in any case, the weather took a remarkable and unseasonable change over the weekend that made this great Northern Thai city go from nearly unbearable to extremely pleasant in just a few short hours.
Look at the chart below, which shows the readings of air-born particles smaller than 10 microns (PM10) recorded at Yupparaj Wittayalai School in the center of Chiang Mai (data from aqmthai.com). A reading above 120 micrograms per cubic meter is considered potentially hazardous to health, and when it gets above 200 people are advised to avoid outdoor physical activity. From a practical point of view, when the PM10 count rises above 200, the majestic mountain right on the edge of town will completely disappear from view behind a thick wall of gray-brown haze.
The smog had been getting progressively worse for several days, and by March 20 it spiked to a reading of over 250 at around 9 am. The next day was even worse—by far one of the worst days I’ve ever seen. The particle concentration increased steadily throughout the morning until it peaked at over 350 micrograms per cubic meter. The smoke covering the city was so thick that four airplanes flying from Bangkok had to turn around when they were unable to locate the runway.
Later that evening, inside my apartment—with all the doors and windows shut—my nose was still filled with the smell of burning trees. If you’ve never experienced choking levels of air pollution before, it might be hard to understand how utterly trapped it can make you feel. I made a promise to myself that this would be the absolute last time I stayed in Chiang Mai during the burning season, and resigned to enduring a few weeks of torture.
Then something amazing happened.
In the late afternoon on the 22nd, the wind began to pick up. It carried with it the distinct smell of summer rain. Within hours the smoke was whipped out of the valley, and the level of suspended particles dropped down to around 30 microns. All day Sunday, the air remained clear. And this afternoon there was a rain shower, with hail also reported in many places near Chiang Mai.
We humans have not done much to show that we can take care of the environment on our own. Had the weather not suddenly changed, I’m quite sure the air quality would have remained beyond hazardous. So whatever force brought the wind and rain out of season to Northern Thailand, I’m extremely grateful for it making the air in the burning season breathable, at least for a short while.