Delhi is set to conduct its first cloud seeding flights between 30 August and 10 September 2025. This initiative aims to reduce the city’s persistent air pollution by triggering artificial rainfall. The project was delayed from its initial July schedule following expert advice from the India Meteorological Department (IMD) and the Indian Institute of Tropical Meteorology (IITM), Pune.
Cloud Seeding Explained
Cloud seeding involves dispersing substances such as silver iodide into clouds to induce rainfall or snowfall. It is used to alleviate water scarcity, reduce hail, or clear fog. Delivery methods include aircraft, rockets, or ground-based machines. The formulation used in Delhi’s project, developed by IIT Kanpur, contains silver iodide nanoparticles mixed with iodised and rock salt. This method can increase rainfall by 5 to 15 per cent when suitable cloud conditions exist.
Delhi’s Air Pollution Challenge
Delhi experiences severe air pollution almost year-round. The city recorded an average PM2.5 level of 175 micrograms per cubic metre during the 2024-25 winter, far exceeding safe limits. This pollution shortens residents’ life expectancy by nearly 12 years compared to World Health Organisation guidelines. The Delhi government views cloud seeding as a potential tool to improve air quality by washing away pollutants through induced rain.
Project Details and Execution
The Rs 3.21 crore cloud seeding project will use five modified Cessna aircraft. Each flight will cover about 100 square kilometres over low-security zones in northwest and outer Delhi. Flight duration is approximately 90 minutes per sortie. The project is titled “Technology Demonstration and Evaluation of Cloud Seeding as an Alternative for Delhi NCR Pollution Mitigation.”
Reason for Date Revision
The initial plan to conduct cloud seeding in early July faced criticism for coinciding with the monsoon season when pollution is lower. Experts clarified that cloud seeding requires existing clouds to be effective. IMD and IITM advised postponing the flights to late August and early September when cloud patterns are more favourable. This timing aims to optimise the chances of successful rainfall induction.
Effectiveness and Limitations
Experts caution that cloud seeding is a temporary measure rather than a long-term solution. It does not address pollution sources such as vehicles or industrial emissions. The technique may be useful during acute pollution spikes but cannot replace sustained pollution control efforts. Conducting trials during the monsoon may not fully represent winter conditions when pollution peaks, limiting the pilot’s predictive value.
Future Implications
If successful, cloud seeding could become part of Delhi’s pollution management toolkit. However, it must be combined with stricter emission controls and sustainable urban planning. The project also marks the growing use of weather modification technologies in urban environmental management.
Questions for UPSC:
- Discuss the effectiveness of cloud seeding as a tool for air pollution control in urban areas with examples from global practices.
- Critically examine the role of meteorological interventions in disaster management and environmental sustainability.
- Explain the causes and consequences of air pollution in Indian megacities. How can policy measures balance economic growth and environmental health?
- With suitable examples, discuss the challenges and opportunities of implementing technology-driven solutions for environmental problems in India.
