Cloud Seeding Trial in Delhi
On October 28, a Cessna 206H aircraft conducted a cloud seeding trial in Delhi amid rising air pollution. The trial was a part of an initiative to reduce pollution scientifically.
Trial Details
- The aircraft took off from IIT-Kanpur, landed in Meerut, and then flew over Delhi, covering areas such as Burari, Mayur Vihar, and north Karol Bagh.
- Eight flares, each weighing 2 to 2.5 kg, were used to dispense seeding material into clouds with 15-20% humidity.
Cloud Seeding Explained
Cloud seeding is a technique to modify clouds with 'seed' particles to increase rainfall. It was first tested globally in the 1940s.
- Cloud condensation nuclei (CCN) or ice nuclei particles are used as seeds to facilitate cloud droplet formation.
- Salts like silver iodide, potassium iodide, or sodium chloride are commonly used as seeding agents.
- Seeding material is dispersed using aircraft, rockets, drones, or flares.
Requirements and Challenges
- Cloud seeding requires a sufficient number of clouds with adequate depth and droplet content.
- Western disturbances, originating from the Caspian or Mediterranean Sea, bring non-monsoonal rainfall to northwest India but may not always be suitable for seeding.
- Monitoring tools are employed to assess cloud characteristics.
Past Experiments and Results
- Cloud seeding has been attempted in India to address drought conditions with mixed results.
- An IITM study noted a 24% increase in rainfall under certain conditions.
Pollution Reduction
- Rain can help wash away pollutants like PM 2.5 and PM 10 through coagulation.
- Successful trials could temporarily disrupt the flow of pollutants.
Concerns and Criticisms
- Doubts persist about targeting the effects rather than the causes of pollution, such as vehicular emissions, industrial output, and dust.
