Chiang Mai smokey season: how bad is it?
When you hear about Chiang Mai there is a good chance that if you are speaking to anyone with any level of experience they will bring up the "smokey season" which is where the AQI (air quality index) in Chiang Mai at times becomes the worst pollution levels anywhere on earth. or so they say.
But I'm here as a near 7 year resident to inform you that a lot of this is blown up by people on the internet that are looking for internet points as they select the worst data points at a certain part of town during a specific time of day instead of looking at the entire picture.
The doom and gloom doesn't help anyone and I will admit that there definitely is a problem here with the crop burning that goes on every year but I also realize that there really isn't anything they can do about it.

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Those of us from the west need to take a step down from our collective soapboxes every now and then and realize that the farming standards that exist in the west are financially impossible over here in Thailand. If they want to remain competitive on the global scale as far as their cash crops are concerned, they need to be able to produce them for a lower price than other nations are paying for them. They are able to accomplish this by doing some corner-cutting I guess. At the end of the day these farmers are not billionaires that just don't GAF, they normally are people that are desperately poor.
I'll get into that at another time but for now I want to explain that Chiang Mai smokey season is in fact, quite bad; but on the flip side it is never as bad as the various websites and media outlets make it out to be. As seems to be par for the course, they cheery-pick their photos to make it look as bad as possible and probably alter the images as well to make it look hellish.
We do have some days where the smoke is just nuts and you cant see the sun because of it, but that is not the norm at all.

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There's plenty to be suspicious about in this picture that is meant to be the real-time AQI in Chiang Mai especially that purple bit that says 223 just a few km (or perhaps less than that ) away from an area where the AQI is 15. how is that possible?
Most days when I walk outside this time of year I will notice a bit of haze. That is normal for this time of year, but if you were to believe the news stories that the government doesn't intercept and shut down, you would probably think that the entire city looks like Silent Hill all day every day. It simply isn't like that. There does seem to be some days that are worse than others and perhaps this is because the government has coordinated the burns so that everyone does it around the same time and just goes ahead and gets it over with.

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this photos is staged, altered, or probably both
Could they prevent the burns? yeah, of course they could, but then the farmers would have no other choice, would probably riot and take over the local police station and the rice markets would collapse in Thailand.
If you have an pre-existing respiratory issue this is not the place for you. If you are super concerned about the potential long-term effects of this, and you probably should be, then you get yourself an air purifyer and when you do have to go outside during these couple of months you wear a real mask, not the face-diapers that do nothing that they handed out for free during Covid.
It's really not anywhere near as big of a deal as the doomsday preachers online make it out to be.
I have a friend who leaves the city for 2 months every year because he has some sort of pulmonary something or other and the particulates seriously annoy him. For most of the rest of us we are likely able to detox our lungs for the rest of the year where the AQI is so good that it is never even discussed. Funny how none of the sites that love to tell you how awful Chiang Mai is never discuss that, huh?
Chiang Mai is still a wonderful place to live and there is a reason why I have never so much as even contemplated leaving here for another city. It has more than enough good to make up for the bad.
For someone who is just landing it might seem a bit ominous but I'm here as a resident to tell you that outside of very rare days you hardly even notice it is happening. Something that really annoys me is when a smoker that I know talks about the the air quality. Shut up dude, you intentionally poison your lungs 20-30 times a day.
So my only suggestion to people would be if you are super-sensitive to this sort of thing than maybe don't plan to come here in March or April because those are the worst months. But if you do come during those times and can deal with the occasional haze, you will get the cheapest prices of the entire year.