Cloud seeding for artificial rain in Delhi-NCR halted due to low moisture levels

A much-watched attempt to spark rainfall over Delhi-NCR has been paused after meteorologists found the atmosphere too dry for the operation to work. The cloud seeding mission—planned as a short-term tool to knock down hazardous smog—will remain on standby until weather conditions improve.

The effort, prepared by a team from the Indian Institute of Technology (IIT) Kanpur in coordination with local authorities, was slated to proceed once a favorable window opened. Real-time observations on cloud structure and humidity, however, showed inadequate moisture in the target clouds, prompting a postponement. Without sufficient water content and the right thermal and wind profiles, seeding agents cannot reliably trigger rain.

Cloud seeding typically involves dispersing microscopic particles—often silver iodide or common salt—into suitable clouds to enhance droplet or ice crystal formation. The method is inherently conditional: operators look for clouds with enough liquid water or supercooled droplets, adequate updrafts, and wind patterns that keep seeded clouds over the intended area. When those ingredients are missing, the chances of a measurable rainout drop sharply.

Project coordinators indicated they will keep monitoring atmospheric parameters such as moisture levels, cloud depth, and wind direction. If and when those factors align, aircraft-based sorties can be launched on short notice. Based on current assessments, the necessary setup did not materialize during the expected window, and operations were therefore held.

The push for artificial rain is rooted in Delhi’s chronic air quality challenges, particularly during the cool season when temperature inversions trap pollutants near the surface. A well-timed shower can remove a portion of airborne particles—especially coarse and fine particulate matter—through wet deposition, offering temporary relief. Yet, scientists emphasize that rain-induced cleansing is short-lived and cannot substitute for emissions cuts from transport, industry, open burning, and other sources.

Experts also caution that the effectiveness of cloud seeding varies widely. Results depend on the microphysics of each cloud system, the amount and type of seeding material introduced, and the match between seeding strategy and prevailing meteorology. Even under promising conditions, outcomes range from modest increases in precipitation to no detectable change, which is why careful, data-driven go/no-go decisions are crucial.

In the meantime, public health guidance remains unchanged. Residents are advised to reduce exposure during pollution spikes by limiting strenuous outdoor activity, using well-fitted masks when necessary, and improving indoor air filtration where possible. Authorities continue to track air quality indicators and implement near-term measures while longer-term strategies to cut emissions progress in parallel.

For now, the cloud seeding aircraft and crews remain ready. If humidity levels rise and clouds with sufficient water content form over Delhi-NCR, the operation could be restarted quickly. Until then, the plan is on hold, waiting for the atmosphere to cooperate.