Archive · 4 Nov 2025
Delhi's Cloud Seeding Experiment for Air Pollution Fails Due to Low Humidity
Imagine clouds are like sponges filled with water.
Sometimes, even if there are clouds, they don't release rain.
Cloud seeding is like giving these clouds a little extra push to make them rain.
It involves spraying special tiny particles into the clouds that help the water droplets stick together and get bigger, so they fall as rain.
The Delhi government tried this to clean the air after a big festival called Diwali, which makes the air very dirty.
They used chemicals like salt and silver iodide.
However, the experiment didn't work because the clouds didn't have enough water vapor, like trying to squeeze water from a dry sponge.
Cloud seeding only works when there's enough moisture in the clouds.
Experts say this is not a good long-term plan to fix dirty air because it only cleans things up for a short time and doesn't stop the pollution from happening in the first place.
Other countries have tried cloud seeding for rain, and it sometimes works, but it can also cause problems like flooding or less rain elsewhere.
Delhi government, in partnership with IIT-Kanpur, conducted a cloud seeding experiment on October 28 to combat air pollution.
The experiment used chemicals like silver iodide, common salt, and rock salt as artificial condensation nuclei.
Cloud seeding requires clouds with at least 50% humidity, but the targeted clouds in Delhi had only 15-20% humidity, leading to failure.
Experts state that cloud seeding is a temporary fix for air pollution and does not address its root causes.
While cloud seeding has been used successfully in other countries for rain enhancement, its application for pollution control is novel and has shown limitations.
- Who
- Delhi government in collaboration with IIT-Kanpur
- What
- Conducted a cloud seeding experiment to alleviate air pollution
- When
- October 28
- Where
- Delhi
- Why
- To provide relief from severe air pollution following Diwali
Cloud Seeding Supporters
Cloud Seeding Skeptics/Critics
Effectiveness for Air Pollution Control
Cloud Seeding Supporters
Cloud seeding, using substances like silver iodide, can potentially induce rainfall by acting as artificial condensation nuclei, which might offer temporary relief from air pollution.
Cloud Seeding Skeptics/Critics
Cloud seeding is not a permanent solution for air pollution as it does not address the root causes and any air-clearing effects are only temporary, lasting a few hours or days.
Conditions for Success
Cloud Seeding Supporters
When clouds have sufficient humidity (around 50% or more) and moisture, cloud seeding can be successful in inducing rainfall, as demonstrated in some international projects.
Cloud Seeding Skeptics/Critics
Cloud seeding is ineffective under clear skies or when clouds have very low humidity (like the 15-20% observed in Delhi), rendering the process useless without adequate atmospheric conditions.
Impact on Natural Rainfall
Cloud Seeding Supporters
When successful, cloud seeding can increase rainfall in specific areas, as seen in countries like the UAE, helping to combat water scarcity.
Cloud Seeding Skeptics/Critics
Cloud seeding can interfere with naturally occurring rainfall patterns, potentially reducing rainfall in nearby regions and causing adverse effects like sudden heavy rainfall and floods.
- Location
- Delhi, India
- Date of Experiment
- October 28
- Collaborating Institutions
- Delhi Government and IIT-Kanpur
- Chemicals Used
- Common salt, rock salt, and silver iodide
- Humidity Level in Targeted Clouds
- 15-20%
- Primary Goal
- To alleviate air pollution
- Underlying Issue
- Insufficient humidity for effective cloud seeding