Northern Thailand is Choking Toxic Smog
The picturesque beauty of Northern Thailand’s mountainous region, once cherished as a delightful transition from winter to summer, has now faded away. Instead of being celebrated for its charm, this period is now infamous as the smog season, spanning from February to April.
Chiang Mai, the northern capital, has consistently held the undesirable title of the world’s most polluted city in 2023, according to the Air Quality Index (AQI). The impact is evident in the healthcare sector, with thousands suffering from respiratory ailments. In the first quarter of 2023, a single hospital recorded almost 13,000 patients seeking treatment for breathing difficulties, reaching its ‘full ward capacity’ due to respiratory issues caused by air pollution.
The smog in the north has a different source than other areas, such as Bangkok, where the air pollution problem is mainly the result of vehicle exhaust and industrial pollution. The primary sources of air pollution in the region are attributed to open burning practices, which include forest fires and the burning of agricultural residues.
The upper Northern region, which includes Chiang Mai, Chiang Rai, Lamphun, Nan, Phrae, Mae Hong Son, Phayao, and Tak, features a wok-shaped topography encircled by mountains. The challenge of escaping polluted air results in the accumulation of a significant amount of PM2.5. The smog dilemma is more pronounced compared to other areas of the nation.
Meteorological conditions exacerbate the situation. During the months of January to March, low-pressure systems from China disrupt air circulation. Calm winds and high air pressure lead to limited vertical air ventilation.
The escalation of biomass burning practices in neighboring countries like Myanmar and Laos has heightened these adverse effects, prompting comprehensive endeavors to tackle and mitigate them on both local and regional scales.
Open Burning
Agricultural practices involve burning for land preparation during the wet season due to socio-economic constraints like limited capital and labor. Open burning also includes clearing deciduous forest areas with fallen leaves. Forest fires result mainly from human activities, including forest product collection. Slash-and-burn agriculture extends uncontrollably into nearby forests. Other factors include hunting, arson, and negligence.
Geography
With its wok-like topography that creates a basin-like configuration, air pollution tends to get trapped within this geographical setting.
Climate
In January to March, low-pressure systems from China affect air circulation in the region, causing stagnant air and PM2.5 accumulation.
Cross-border Smog
Smog increases from Myanmar and Laos due to expanding border agricultural zones, burning crops like sugar cane and maize. Severe issues occur in border areas like Muang district of Mae Hong Son, Mae Sot District of Tak, and Mae Sai District of Chiang Rai.
PM2.5 Why should we care?
PM2.5, or atmospheric particulate matter with a diameter under 2.5 micrometers, represents particles about 3% of the width of a human hair. These particles are so minuscule that they require an electron microscope for detection.
The Silent Killer
The impact of PM2.5 air pollution on health has become more pronounced. Scientific data reveals that there are 40,000 Thais deaths annually linked to PM2.5 exposure, with a 7-fold increase in lung cancer risk compared to areas with normal air quality.
Daily PM2.5 exposure correlates with more hospitalizations for cardiovascular and respiratory issues, emergency visits, and fatalities. Prolonged exposure is linked to higher heart disease mortality, increased chronic bronchitis, reduced lung function, and lung cancer rates.
Certain groups, such as individuals with heart and respiratory ailments, pregnant women, children, and the elderly, are notably vulnerable to the consequences of particle pollution.
Economy Decline
Economic Plummet
Chiang Mai, being a prominent tourism and transportation hub, attracts millions of international visitors annually. Nevertheless, its tourist numbers decline during the smog season from January to April. The Thai Chamber of Commerce has concurred that the issue of toxic dust in the ten northern provinces incurs a cost of at least 163,313 million baht per year to the Thai economy.
Household Burden
Over the years, individuals in Chiang Mai have shouldered their well-being expenses, purchasing masks and air purifiers, and covering their medical costs. This incurred an additional cost of 3,518 Baht per person per year.