IIT Kanpur tests artificial rain: What it is and now it works

New Delhi: The Indian Institute of Technology Kanpur (IIT-K) has been working on creating artificial rain through cloud seeding for over five years. The concept involves using chemicals to increase the chances of rainfall to help clear pollutants and dust from the air. Here’s all you need to know about this technology.

What is cloud seeding
Cloud seeding, also known as artificial rain, is a weather modification technique to induce rains in water-starved areas. It is also used to disperse fog banks near some airports.

How does cloud seeding work
Scientists use aircraft to inject silver iodide, potassium iodide, dry ice (solid carbon dioxide), liquid propane or salts into clouds to mimic ice nuclei.

Clouds often lack naturally occurring ice nuclei. So, injecting them with silver iodide particles (which are very similar in structure to ice) and other substances increases the number of nuclei leading to rains.

How does cloud seeding or artificial rain happen
Injection of such particles makes clouds more efficient at generating ice crystals that either fall as snowflakes or melt to produce raindrops, depending on temperatures in and beneath the cloud.

The amount of rain or snow a cloud can produce depends on a balance between the number of ice nuclei inside it and the amount of water available to grow around those nuclei.

Where is cloud seeding tested in India
IIT Kanpur successfully tested the artificial rain technology over a limited area on its campus. It’s also tested by different scientific bodies in water-starved regions of Maharashtra, Karnataka, and Andhra Pradesh.