Global air quality worsened significantly in 2025, with only 14% of cities meeting the World Health Organization’s PM2.5 guideline, as reported by IQAir’s World Air Quality Report. This marked a decline from the previous year when 17% of cities met the standard. Severe weather events like wildfires and dust storms, exacerbated by climate change, were major contributors to the decline.

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The report highlighted Thailand’s position as the 48th most polluted country globally, with an average PM2.5 concentration of 17.8 µg/m³, showing slight improvement from the previous 19.8 µg/m³. Despite this improvement, Thailand remained well above the WHO guideline of 5 µg/m³. Pakistan was identified as the most polluted country, registering the highest PM2.5 levels at 67.3 µg/m³, with Bangladesh and Tajikistan following closely.

South Asia maintained its status as the most polluted region, with New Delhi among the most polluted capitals. Various sources, including transportation, industrial emissions, and construction dust, contributed to these high levels. The report stressed the ongoing issue of transboundary pollution, particularly in East and Southeast Asia, where pollutants often cross borders, complicating efforts to maintain air quality.

Within Thailand, Om Noi Municipality recorded the highest PM2.5 levels at 32.2 µg/m³. The global ramifications of air pollution remain significant, with the WHO estimating that outdoor air pollution contributes to 4.2 million premature deaths annually. Frank Hammes, IQAir’s global chief executive, emphasized the need for ongoing efforts and access to real-time data to protect public health and achieve cleaner air.

The economic impact is profound, with the World Bank estimating annual global damages from air pollution at approximately US$4.5 to US$6.1 trillion. In light of these findings, calls for international action are intensifying, focusing on reducing fossil fuel use and improving air-quality monitoring. Health experts underline the importance of coordinated efforts at all levels as climate change intensifies pollution's frequency and severity, reported The Nation.

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  Adapted by ASEAN Now · The Nation · 25 Mar 2026

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What’s driving this?

The same thing scientists have been warning about for decades: a hotter world means more wildfires, more dust storms, more stagnant air, and more pollution events.

The report itself links worsening air quality to climate‑driven extreme weather.

per report "Wildfires, bolstered by climate change, played a primary role in degrading global air quality in 2025." That may be true in N America (Canada is most polluted in N America.... who'd a thought?) and Australia, but I'd hazard a guess that agricultural burning is major contributor here (Don't think those are "WILD fires"... they are SET fires")

Helps explain why Chiang Mai is 3rd most polluted world city but Bangkok is way down there at #32. Many times air is worse here in Jomtien than it is in Bangkok.

Humans haven't learned the old adage "You don't sh*t where you eat"

This is the second year up here in Northern Thailand where the air quality has been significantly BETTER that years previously. There are now burning laws that are actually being enforced, at least where I live, and the amount of forest burning has dropped by about 90%. Ag burning was never a problem in where we live.

17 hours ago, Jim Waldron said:

a hotter world means more wildfires

A hotter world sends the loonies out to commit arson in order to make a case for the "Global Warming" scam.