Cloud seeding is a weather modification technique used to induce or enhance rainfall by dispersing substances into the air that serve as cloud condensation or ice nuclei. These substances (like silver iodide, sodium chloride, or potassium iodide) encourage water droplets in clouds to cluster together and fall as rain.
How Cloud Seeding Works:
- Aerial Spraying: Aircraft or drones release the seeding agents into suitable clouds.
- Condensation: The agents attract tiny water droplets or ice crystals.
- Rainfall Formation: These droplets merge, grow heavier, and eventually fall as rain.
Impact on Pollution in Delhi:
Delhi faces severe air pollution, especially during winter, due to factors like stubble burning, vehicular emissions, and weather stagnation. Cloud seeding can help temporarily by:
- Washing Out Pollutants: Rainfall helps remove dust, PM2.5, PM10, and smoke particles from the air, significantly improving Air Quality Index (AQI) for a few days.
- Reducing Smog: Rain breaks down smog layers, improving visibility and reducing respiratory distress.
- Short-Term Relief: The effect usually lasts a few days to a week—until pollutants accumulate again.
- Boosting Water Resources: In the long term, it can help replenish groundwater levels and support agriculture.
Limitations & Concerns:
- Weather dependency: It only works if suitable clouds already exist.
- Temporary solution: It doesn’t tackle the root causes of pollution (emissions, waste burning, etc.).
- Environmental questions: Use of certain chemicals like silver iodide needs to be regulated to prevent soil and water contamination.
Cloud seeding can provide short-term relief from pollution in Delhi by cleansing the air and improving visibility. However, it should be treated as an emergency or supplementary measure, not a permanent solution. Long-term improvements require tackling emission sources, promoting clean energy, and sustainable urban planning.
