The Guardian today reports on how bad pollution in Thailand gets. The worst periods are during the cool season, which, of course, is when I prefer to visit!

https://www.theguardian.com/world/2023/mar/27/air-pollution-chokes-thailand-as-campaigners-call-for-stricter-laws-chiang-mai

From the Nation

Greenpeace urges Thai government to declare emergency over toxic air

The government should declare air pollution an emergency so that its agencies can collaborate effectively to deal with the PM2.5 crisis, Greenpeace Thailand's air-pollution campaigner Alliya Moun-ob said on Thursday.

Alliya also warned that the fire that has engulfed Khao Laem forested mountain could spread to nearby communities in Nakhon Nayok province, make people sick, and destroy property.

Firefighters were still battling the blaze in the province in central Thailand on Thursday.

In the North, air-pollution levels were among the worst in the world on Thursday.

Chiang Mai’s air-quality index surged to 237 on Thursday, making its air the most polluted of any city in the world, according to the website IQAir.

Delhi was second, with an index of 194.

Alliya said that what is happening in upper Thailand is not new. It happened five years ago when the El Niño weather phenomenon exasperated the dry season, but there were few machines to detect PM2.5 then so people were not as aware of the crisis as they are now, she explained.

PM2.5 is fine dust less than 2.5 micrometres in diameter. It can be fatal. Long-term exposure damages respiratory systems and blood vessels, Alliya said.