Chiang Mai Air Pollution Ranked #6 Worst Globally

Its no secret to those living in Thailand that the air pollution problem in Chiang Mai occurs each & every year around this time. Air Visual) monitors the quality of air around the world - its 'Major Cities Ranking' lists the top 10 most polluted areas. Today, Chiang Mai was ranked #6 worst in the world for air pollution.

Unfortunately many planning a visit to Chiang Mai may have no idea of the level of pollution they will encounter should they visit the region between the months of February to April.

Chiang-Mai-Air Source/Credit:

Pollution of course is nothing new in some Northern areas of Thailand. Each year between the months of February & April, 'slash-and-burn' farming takes place in a number of neighbouring countries surrounding the border. In the past 24 hours readings have fluctuated between 100 (moderate) to 185 (unhealthy). For those suffering from respiratory problems including asthma, the pollution levels may cause issues for sufferers.

Air-Pollution-Ranking-March-2018 Source/Credit: Air Visual's Major Cities Ranking

Pollution kills roughly seven million people worldwide each year with air pollution cited as the cause of one in eight deaths, according World Health Organization. Unfortunately, Asia faces the greatest challenges in the future as this is where the majority of the deaths occur.

An article written in 2014 by Gennie Gebhart (a 2013-2014 Luce Scholar at the Chiang Mai University Library in Chiang Mai, Thailand. She studied natural resource and environmental economics at the University of Washington) provides a detailed explaination around the primary cause of pollution in Chiang Mai. I have reproduced an extract of this excellent article for those seeking to drill down on the causes of air pollution in the region.

Transboundary Pollution in Northern Thailand Causes Dangerous Levels of Smog

Thai media and officials often blame the pollution on swidden (or shifting) agriculture. Swidden farmers typically cultivate plots of land in cycles. A particular plot of land is cultivated for a year, then allowed to lie fallow and recover for multiple years before being used again. In the meantime, farmers shift to a different plot of land. In the long term, swidden farmers rotate among several plots, always moving toward old, previously cultivated land. Most swidden farmers burn plots of land in order to clear and fertilize them before planting. This practice typically falls between February and April, during the worst of the haze, and has sparked intense criticism and controversy.

AQI-Air-VisualAir Quality Index Chiang Mai

Characterizing swidden farmers as the pollution’s primary cause, however, misses the extensive range of burning activities during this season. In addition to swidden farmers clearing fields, a smaller proportion of farmers may burn land in order to clear forests and expand crop fields, to flush out game, or to trigger the growth of specific mushroom varieties. Further, virtually all methods of farming produce organic waste. The faster, cheapest, and least labor-intensive way to dispose of it is burning, which is common.

Bangkok-AQIAir Quality Index Bangkok

Monoculture, the practice of growing a single crop over a wide area, creates especially large amounts of agricultural waste. Thailand’s recent surge in contract farming with agricultural conglomerates like Charoen Pokphand has encouraged intensive monoculture of corn and other cash crops. Ethanol-use policies have added extra incentives with guaranteed high prices for corn. The result has been unprecedented amounts of corncob waste. Chiang Mai Province’s Mae Chaem District alone produces – and burns – over 37,000 tons of corncob waste every year.

Phuket-AQIAir Quality Index Phuket

The pollution’s sources go beyond farming. Accidental forest and grass fires during this hot, dry season are among the primary sources of smoke. Since February 1, Chiang Mai’s Offices for National Resources and Environment have tracked 979 forest fire sites, with damage to an estimated 5,026 rai (1,987 acres) of national park and reserve land.

Perhaps most critically, pollution sources extend beyond Thailand’s borders. GISTDA (Geo-Informatics and Space Technology Development Agency) satellite monitoring shows clusters of burning “hotspots” across peninsular Southeast Asia. Chiang Mai in particular experiences drastic effects because of its location in the Chiang Mai-Lamphun valley, where smoke from neighboring Myanmar and Laos is prone to settle.

Screen-Shot-2018-03-19-at-11.30.56-am-1 Air Visual's Health Implications Chart

With its transboundary sources, Chiang Mai’s haze problem requires international cooperation. ASEAN member countries have made joint efforts in monitoring, preventing, and mitigating transboundary haze since 1997. In addition to a Regional Haze Action Plan, ASEAN member states adopted the ASEAN Agreement on Transboundary Haze Pollution in 2003. More recently, ASEAN has introduced simulation exercises, management strategies, and zero-burning best practices.

Even with this international framework, local efforts in Northern Thailand have proven difficult to coordinate. Attempts to impose 90-day burning bans, or even offers of a 5,000 THB (about $150) reward for information about outdoor burning, have not produced results.

Air-Pollution-Live-Air-Quality-Index-AQI Source/Credit: Air Quality Index: Status Monday March 19, 2018 Air Visual

The Pollution Control Department has urged authorities to quickly address air pollution by controlling burning in open areas. People were asked to not burn their garbage, farm detritus or fallen leaves. “If there is thick smog, avoid going outdoors,” the department advised. “If you really need to go out, wear masks.” The statement added that people who were developing health problems linked to smog should see a doctor, Thailand's The Nation Newspaper reported this week.

Whilst the air pollution index was high during the time I wrote the article, its important to keep the situation in context with not only other areas around the world, but also how long the problem persists. To keep a balanced view of the timeline the pollution in the area exists, check out the Air Pollution Index regularly. Here's the link.

Air Pollution Quality Index

Sandra Hawkins

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