Successful rainmaking operations drastically reduce Bangkok’s pollution levels

Pollution levels across Bangkok and neighbouring areas nosedived yesterday as a result of successful rainmaking operations carried out east of the capital. The operations saw a significant reduction in the concentration of ultra-fine pollutants in the air, bringing it back within the safety threshold.

Supis Pitakham, the director-general of the Department of Rainmaking and Agricultural Aviation, confirmed that the cloud-seeding operations were conducted from Dec 16-18 as a response to the surge in PM2.5 levels observed in the city the previous week.

Supis revealed that two Cessna Caravan aircraft were employed for two triumphant cloud-seeding operations on Saturday. The operations focussed on Ban Bung district in Chon Buri and Khong Khuan district in Chachoengsao, leading to a fall in PM2.5 levels in those areas.

On Sunday, the aircraft conducted two more cloud-seeding operations, this time focussed on Phanom Sarakham in Chachoengsao and Pak Phli district in Nakhon Nayok. The aftermath of the operation was marked by light rain in Ongkharak district in Nakhon Nayok and Nong Sua district in Pathum Thani.

Supis confirmed that the successful rainmaking manoeuvres had a considerable positive impact on the air quality across Bangkok and neighbouring provinces. As of yesterday morning, the PM2.5 levels in the city were reported to be within the safe exposure threshold, reported Bangkok Post.

He also emphasised the necessity of meticulously planned rainmaking operations in and around Bangkok and its neighbouring provinces to ensure success.

Vital factors

The direction of the wind is a vital factor to consider for these operations. If the wind blows from the east, the operation should be executed over Rayong, whereas if it originates from the west, Kanchanaburi should be the target.

Supis also pointed out that to comply with international aviation rules, these rainmaking efforts must be carried out at least 70 nautical miles (roughly 129 kilometres) away from Suvarnabhumi and Don Mueang airports.