♥ Lovely that Han Thomas has allowed us to share his latest observations about Chiang Mai smoke haze ….
The hazy season: that time between roughly Valentine’s and Songkran when particulate matter pollution peaks throughout the Northern region, as well as neighboring countries. There are bad spells and less bad spells during this time, which you can readily see as the air becomes murky and Doi Suthep mountain disappears from view. Also within the course of a day pollution fluctuates, with afternoons often being a bit better than mornings.
This is not new, the pattern has been the same for the past 20+ years and possibly longer; data has been gathered since 1996. There has been a *slight* improvement over the years, but nowhere near enough to make a difference: March remains a very crappy month to be in Northern Thailand, and even dangerous to people with a respiratory condition, children and the elderly. March is a really good time for a beach holiday, or going further afield. When staying put, air filters at home help a lot and some people consider 3M face masks when going outside.
Some FSM’s (Frequently Seen Misconceptions) are below. (I’d say Frequently Asked Questions, but.. you know; Internet.)
1. “Can I just leave town and go to Pai or Chiang Dao or something?” No. It’s not primarily an urban thing. The cause is mainly agricultural burning and forest fires combined with weather patterns. So leaving town does little, and actually the more North you go, the worse it gets most of the time. You CAN of course go South, but then you need to go pretty far; the Andaman coast is good. The Eastern Seaboard (Pattaya, Samet, etc.) is ‘okay’; it also gets some haze now and then.
2. “Is the Thai government trying to to deceive me?” No. Or… at least not intentionally I think. The Pollution Control Department (PCD) is the reason you even have near-real-time air quality data, including PM2.5 data for the smallest particles. This data is used by all air quality monitoring sites and apps, such as aqicn.org. Furthermore there are now two independent monitoring stations run by Prem and CMIS schools, and their data seems to match the government data quite well. However, Thailand’s newer and quite strict PM2.5 standard is not in official use yet by the government, also because they don’t yet have a PM2.5 monitoring capability for the whole country. This results in officials saying that levels are not exceeded, which is true when referring to the old standard. This existing PM10 based standard is often portrayed in news articles as ludicrously irresponsible or intentionally misleading and I don’t think that’s accurate: the USA only moved to implementing the PM2.5 based standards in the mid-2000’s. So you can say that Thailand is a decade or so behind in implementing newer standards that are now common in the Western world. So.. firstly let’s be thankful for them supplying the data, but get your alerts and health advisory elsewhere until Thailand moves to the new PM2.5 based standard. There are indications that action is being taken such as the government sanctioned burning ban (starting 1 March this year), and forest fire fighting efforts.
3. “I’m staying put. How am I affected?” When using the US EPA scale there is a health advisory for every level / color code. Note that not everyone is the same: some people completely don’t notice it even during the worst times, others have symptoms at even moderate levels. There is no right and wrong here, you know best how you feel, and the health impact information is readily available. It would make for friendlier discussions if people without symptoms don’t claim that therefore others are just being whiners, and that more pollution-sensitive people don’t claim the sky is falling when levels go into the red. They always go into the red, for several days or weeks, every year, even relatively good years like 2017.
4. “When does it end?” This depends again on what you consider ending and what level is acceptable to you. But we’re mostly out of it by Songkran, so that’s mid April, see the graph below. Note that this is before it starts raining regularly. Rain does clear up pollution, but it’s not required: a change in weather patterns will also do that. But again, if you want ‘green’ values then that doesn’t happen until June, and please realize that a whole month being green on average is not common at all, even in the rainy season, and for any region in Thailand/Asia including the South. If you want green, go to Canada or Norway.
5. “What can I do when it’s bad?” Follow the US AQI scale health advisory, which typically means to avoid outdoor exercise, and staying indoors is better than outdoors even without air filters. It is worth it to buy the 3M ‘Filtrete’ material (e.g. at Home Pro) to stick to your air conditioners. Put it there after Valentine’s Day, and replace mid March. Or you can buy a dedicated air purifier; it doesn’t matter much which one you get (compared to not having one at all), but do make sure you can easily get replacement filters. Toshiba is good, and replacement filters can be purchased direct from their Bangkok distributor for not too much money.
6. “Causes and solutions?” I’m not going into that, it would turn even longer, plus it becomes more opinion-based. Feel free to do so in the comments, though. Discussion and raising awareness is good. Finally some numbers for the past years: Raw PM2.5 numbers on the left, the same values converted to US EPA numbers & pretty colors on the right. (Note that these are monthly *averages*. An average means that some days are higher, and others are lower. 😉 )