Dozens of drones urged farmers to "stop the fire" as air pollution continues to choke northern Thailand.

The flying gadgets spelled out messages such as "Our eyes are irritated" and "Our throats are sore", detailing the impacts of the persistent smog during a drone light show in the Muang district of Chiang Rai province on April 2.

The drones also flashed other messages such as "Save the North" as well as a map pin with the label "Chiang Rai" on it.

The event was organised by the Radio Control Airplane Modeller Sport Association (RCSA), the Ministry of Higher Education, Science, Research, and the Innovation's National Research Council of Thailand.

Chiang Rai is among Thailand's northern provinces suffering the most in recent weeks from air pollution that is caused by farmers' agricultural burning.

Scientists found that smog is at its worst in the country when farmers burn waste crops to cheaply clear their land between late October and April. It has been worsened in recent years by rising demand for food and agro-business lobbyists that can stifle the government's control over farmers.

The seasonal lack of wind and rain, combined with a winter low-pressure system in which cold air is trapped closer to the ground by warm air above – hampers the pollution from being dispersed naturally by the wind.

Thai government officials have been criticised for failing to tackle the country's air pollution crisis, with bizarre measures such as spraying water into the air and giant purifiers having no impact.

Data scientist engineer Worasom Kundhikanjana said: "PM 2.5 pollution has a seasonal trend in Bangkok and the northern provinces, but has only recently received public attention. During this winter haze, the harmful particle pollution level is high throughout the day, including on weekends.
Unfortunately, spraying water into the air does not appear to be effective, since the volume of water is minuscule compared to actual rain".

He added: "With the start of the monsoon season, the weather in Bangkok will get better, and public attention on this issue will likely fade. However, without immediate policy measures, the problem will come back again next winter".

Dozens of drones urged farmers to 'stop fire' as air pollution continues to choke northern Thailand.

The flying gadgets spelled out messages such as 'Our eyes are irritated' and 'Our throats are sore', detailing the impacts of the persistent smog during a drone light show in the Muang district of Chiang Rai province on April 2.

The drones also flashed other messages such as 'Save the North' as well as a map pin with the label 'Chiang Rai' on it.

The event was organised by the Radio Control Airplane Modeller Sport Association (RCSA), the Ministry of Higher Education, Science, Research, and the Innovation's National Research Council of Thailand.

Chiang Rai is among Thailand's northern provinces suffering the most in recent weeks from air pollution that is caused by farmers' agricultural burning.

Scientists found that smog is at its worst in the country when farmers burn waste crops to cheaply clear their land between late October and April. It has been worsened in recent years by rising demand for food and agro-business lobbyists that can stifle the government's control over farmers.

The seasonal lack of wind and rain, combined with a winter low-pressure system in which cold air is trapped closer to the ground by warm air above – hampers the pollution from being dispersed naturally by wind.

Thai government officians have been criticised for failing to tackle the country's air pollution crisis, with bizarre measures such as spraying water into the air and giant purifiers having no impact.

Data scientist engineer Worasom Kundhikanjana said: 'PM 2.5 pollution has a seasonal trend in Bangkok and the northern provinces, but has only recently received public attention. During this winter haze, the harmful particle pollution level is high throughout the day, including on weekends.

'Unfortunately, spraying water into the air does not appear to be effective, since the volume of water is minuscule compared to actual rain.

'With the start of the monsoon season, the weather in Bangkok will get better, and public attention on this issue will likely fade. However, without immediate policy measures, the problem will come back again next winter.'