I have lived in this country for a long time but have only lived in Chiang Mai for a few months. So far I love the drop in humidity, the decreased temperature, and the wide-array of restaurants, bars, and general activities that living in a city of a million people brings with it. However, I have never lived somewhere that ranked really high on the global pollution index and right now anyway, Chiang Mai is number one on the planet

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While the numbers are not huge, tourism has dropped 15% to the region as it approaches the famous Songkran festival as Chiang Mai is the number one destination in the world for the celebration of this holiday. It has been estimated that 10,000 hotel reservations have been cancelled due to the pollution index. 400 flights have been cancelled to nearby Mae Hong Son because the smog is so bad there that pilots can't see the airport or the runway.
Personally, I am not noticeably affected by the pollution although I am certain that it is having some sort of effect on me. As 25 year on-and-off smoker, perhaps my lungs don't even notice the difference. I knew that this dirty habit would come in handy one day.
Some people are of the impression of "well it can't be that bad..." Well, it can be, and it is.

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These images are completely undoctored, and you do not need to look very hard in order to make your own. We were actually a bit surprised yesterday when although it was for just a little while, we saw a cloud... not a cloud of smog, but an actual cloud. The smog is so think that although it is daytime, you can not see the sun and we haven't noticed the moon in months.
At the moment it appears as though the government is remaining quite silent on this and the other day I was near a national park where there were soldiers that were meant to be busting people for burning of land (the primary source of the smog) but despite the fact that I could literally see smoke rising from the mountains just behind where we were eating, the soldiers just sat there. I suppose I shouldn't be surprised that the government has a tendency to embrace inaction.

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The tourists taking notice of this and changing their plans is unfortunate for the business owners but in a way this is the only way anything is going to be done. The govt officials are very aware of what is causing the problems, but unsurprisingly do nothing about it until it has gotten out of control. I think that the fact that none of us have seen the sky in several months and the fact that many residents actually move away for a few months is a pretty good sign that the problem is already out of control.
I suppose the only silver lining to this situation is the fact that this is a seasonal thing and for the rest of the year Chiang Mai is not like this. I do hope that something can be done in the future because if whatever is causing this is allowed to continue unchecked, it is likely only going to get worse.