Specialized aircraft stood primed on runways in Kanpur and Delhi today to trigger emergency artificial rain, as a choking blanket of toxic smog drove the capital's Air Quality Index to 308.
The city gasped under the 'very poor' category.
Flight crews and atmospheric scientists from IIT Kanpur are awaiting a single operational variable: sufficient moisture over the capital's airspace. One aircraft retrofitted with chemical seeding racks remains parked at IIT Kanpur, capable of reaching Delhi within an hour of clearance. A second aircraft sits on immediate standby inside Delhi. If viable cloud formations gather at target altitudes, pilots will scramble to disperse precipitation-inducing agents across the city's sky.
Without natural showers in sight, authorities view atmospheric intervention as an immediate mechanical flush to pull particulate matter out of the lower atmosphere.
The operation relies on releasing chemical nucleating agents—chiefly silver iodide and dry ice—into pre-existing clouds to force moisture condensation into raindrops. The technique disperses particles via airborne dispensers, ground generators, or rockets to accelerate precipitation in moisture-starved air parcels.
Yet the process demands strict meteorological prerequisites that technology cannot forge on its own.
| Operational Parameter | Trial Specification |
|---|---|
| Current Delhi Air Quality Index (AQI) | 308 ('Very Poor') |
| Primary Flight Staging Base | IIT Kanpur (1-Hour Flight Time) |
| Secondary Aircraft Location | On Standby in Delhi |
| Seeding Compounds | Silver Iodide, Dry Ice |
| Recent Trial Altitude (IGI Airport) | ~30,000 Metres |
| Baseline 2024 Trial Altitude | ~10,000 Metres |
| Operational Trigger | Cloud Height & Ambient Moisture |
The standby posture follows two unsuccessful high-altitude test runs conducted near Indira Gandhi International Airport in late October. Those missions saw aircraft release seeding agents at an altitude of approximately 30,000 metres—three times higher than the 10,000-metre operational ceiling utilized during initial tests last year.
Neither flight produced rain. IIT Kanpur researchers concluded that sub-critical moisture volumes inside the clouds starved the nucleation process, preventing droplet coalescing.
The framework stems from a formal Memorandum of Understanding signed between the Delhi government and IIT Kanpur, drafted to provide rapid aerosol suppression during peak winter smog spikes. Regulatory clearances and unstable weather patterns stalled flights for months before the late-October runs.
Environmental researchers caution that aerosol washouts provide only transient relief rather than structural abatement.
We aren't tackling pollution at the source, so cloud seeding will not help reduce pollution levels in the long run. We can deploy it on days when pollution levels skyrocket, for example, a day after Diwali, but it isn't a solution.
Sunil Dahiya, Founder and Lead Analyst at Envirocatalysts
IIT Kanpur radar teams will track localized moisture bands throughout the afternoon. Flight controllers will authorize takeoff only if overhead moisture hits the precise physical threshold required for condensation.