Cloud Seeding Trials in Delhi

Summary of Cloud Seeding Trial in Delhi

Event Details:

• Date of Experiment: October 28, 2025
• Aircraft Used: Cessna 206H
• Locations Covered: Burari, Mayur Vihar, North Karol Bagh, and other areas within Delhi.

Objective:

• The cloud seeding experiment aims to mitigate air pollution in Delhi, which has seen a recent increase. This is described as the first major attempt to reduce pollution via scientific means in India.

Key Features of Cloud Seeding:

• Definition: Cloud seeding is a weather modification technique involving injecting cloud condensation nuclei (CCN) or ice nuclei into suitable clouds to induce precipitation and increase rainfall.
• Initial Global Use: The technique was first tested in the 1940s.
• Dispersal Method: Flare devices containing seeding materials (salts like silver iodide or sodium chloride) were attached to the aircraft’s wings and dispensed into the clouds. Eight flares, each weighing approximately 2-2.5 kg, were used during the experiment.

Conditions for Cloud Seeding:

• Appropriate cloud types and sufficient humidity (15-20%) are essential for successful cloud seeding. The presence of a western disturbance facilitates cloud formation in Delhi during winter.
• Monitoring tools are employed to assess cloud characteristics and moisture content.

Scientific Basis:

• When raindrops fall through the atmosphere, they attract aerosol particles, effectively washing away pollutants, including PM 2.5 and PM 10. This process is known as coagulation, which reduces airborne contaminants.

Challenges and Considerations:

• Prior attempts at cloud seeding in India have focused predominantly on drought relief with varied success. There are doubts regarding its efficacy in addressing ongoing air pollution, which primarily results from vehicular emissions, industrial activity, and seasonal factors like stubble burning.

Official Comments:

• Officials, including Delhi Environment Minister Manjinder Singh Sirsa, noted the urgency of reducing pollution, indicating that similar cloud seeding trials would be conducted throughout the winter if weather conditions permit.

Context and Implications

• Historical Context: Cloud seeding has seen limited application in India, mainly targeted at addressing droughts rather than air quality.
• Government Initiatives: As air quality continues to be a pressing environmental issue, the trial adds to ongoing discussions about innovative solutions to combat urban pollution.
• Future Prospects: Successful application of cloud seeding could provide temporary relief from pollution, but systemic solutions targeting the underlying causes will be crucial.

This cloud seeding initiative highlights the intersection of technology, environmental policy, and public health, showing potential paths forward in addressing critical urban environmental challenges.