Bangkok: The Royal Rainmaking Department is ramping up its operations to address the rising PM 2.5 dust levels, with plans to increase the number of flights aimed at combating the pollution. The Director-General of the Royal Rainmaking Department has disclosed that measures are being fast-tracked to establish multi-layered barriers to intercept transboundary dust, with units in Hua Hin, Rayong, and Khon Kaen functioning at full capacity. Preparations for night flights are underway should dust levels reach critical thresholds. The "penetrating the atmosphere" technique, which has been employed, effectively reduced dust levels by nearly half yesterday.
According to Thai News Agency, Mr. Rachen Silapraya, Director-General of the Department of Royal Rainmaking and Agricultural Aviation, reported that PM2.5 levels in Bangkok and surrounding areas continue to surpass the standard levels in the morning, exceeding 37.5 micrograms per cubic meter in numerous locations. Meteorological evaluations reveal weak ventilation and stagnant air near the surface, coupled with increased hotspots from both domestic sources and neighboring countries like Cambodia and Laos, resulting in persistent dust accumulation. Domestically, this is mainly due to sugarcane burning in the Northeast and rice field burning around Bangkok.
The Director-General stated that he has ordered an increase in both aircraft numbers and flights for rainmaking operations, utilizing the "atmospheric penetration" technique and dry ice dispersal. This approach has significantly reduced air pollution levels, with certain areas experiencing a reduction from 80 to approximately 40 micrograms per cubic meter, changing the pollution level from orange to yellow in the evenings. Currently, three main operational units are active: the Hua Hin unit in Prachuap Khiri Khan province, with four aircraft (one Super King Air and three CARAVAN aircraft) and a weather monitoring aircraft; the Rayong unit, with three aircraft (one CN and two CASA aircraft) operating in areas including Prachinburi, Nakhon Ratchasima, Chonburi, and Khao Yai to prevent dust from entering Bangkok; and the Khon Kaen unit, which began operations on January 15th, using three CASA aircraft to focus on reducing dust from sugarcane burning in the Northeast.
Preparations are also underway to establish operational units in the northern region, specifically in Tak and Phitsanulok provinces, starting February 1, 2026, to combat potentially severe dust pollution towards the end of the winter season. Additionally, the Rayong unit is planning "night flights" to suppress dust levels that tend to increase in the evening if they do not decrease.
Planning is currently focused on using air pollution levels from different periods of the previous year to determine action plans. With Bangkok recording its highest PM2.5 levels on February 24th in 2025, air pollution levels have been monitored since the start of this year for comparison. The Royal Rainmaking Department's atmospheric drilling operations are serving as a supporting measure, alongside controlling pollution sources in areas overseen by each agency.
However, the number of hotspots remains a concern, as neighboring countries have reported numerous hotspots. Furthermore, illegal burning in agricultural areas surrounding Bangkok, particularly at night, results in persistently high levels of particulate matter in the mornings. However, yesterday's atmospheric drilling operation showed a significant reduction in particulate matter levels, dropping from orange to yellow. Mr. Rachen urges the public, especially those in agricultural areas around Bangkok, to refrain from burning during this month to significantly reduce particulate matter in the capital city.
The Royal Rainmaking Department affirms its readiness with aircraft, rainmaking chemicals, personnel, and air quality monitoring systems. They will monitor meteorological conditions throughout the day and adjust flight plans as needed. The public, especially vulnerable groups, are advised to avoid outdoor activities and wear face masks to protect against dust if necessary.