Cloud-Seeding Trials Across National Capital Region (NCR)

Syllabus: GS3/Science and Technology, Environment

Context

• The Delhi Cabinet approved a Rs 3.21-crore project for conducting five cloud-seeding trials across the National Capital Region (NCR) amid the fight against pollution.

What is Cloud Seeding?

• Cloud seeding is a weather modification technique aimed at enhancing precipitation from clouds by introducing substances that act as cloud condensation or ice nuclei.
• Method: Aircraft or rockets disperse seeding agents like silver iodide, potassium iodide, or dry ice (solid carbon dioxide), or liquid propane into the atmosphere.
• Purpose: Stimulate rainfall, reduce dust, suppress hailstorms, and improve air quality by settling particulates.

Suitable Conditions for Cloud Seeding

• Cloud seeding requires existing clouds; it will not produce rain out of thin air.
• Not all types of clouds are suitable for seeding. Clouds must be deep enough and of a suitable temperature (between -10 and -12 degrees Celsius) to be seeded effectively.
• The wind must be below a certain speed. These conditions are most common in mountainous areas.

Concerns with Cloud Seeding

• Use of Chemicals: Some chemicals are potentially harmful to the natural environment. There is concern about soil and water contamination, especially affecting plants and crops that rely on rainwater for nourishment.
• Redistribution of Rainfall: Artificially inducing rainfall in one area may deprive adjacent areas of their natural precipitation, potentially triggering drought-like conditions elsewhere.
• High Cost: Cloud seeding requires specialized aircraft, meteorological expertise, and precision timing, making it a cost-intensive initiative.

Concluding remarks

• Cloud seeding offers a technological solution to mitigate the immediate impact of air pollution in NCR, especially during critical months. 
• However, it should be part of a multi-pronged approach involving emissions control, green infrastructure, and public health measures.

Source: TH