Karnataka Government Faces Questions Over Timing and Viability of New Cloud-Seeding Programme

The Karnataka government launched a cloud-seeding programme worth around 28 crore rupees in September to address rainfall deficits in drought-affected parts of the state, drawing questions about its viability late in the monsoon. Cloud seeding is a weather modification technique that introduces particles into suitable existing clouds to influence how precipitation forms, though it cannot create new clouds and its effect on rainfall is hard to measure.

Expert Concerns And Context

Weather experts and senior India Meteorological Department officials have cautioned that atmospheric conditions are not favourable for the effort in Karnataka. G.S. Srinivasa Reddy, former director of the Karnataka State Natural Disaster Monitoring Centre, noted that 17 of the 26 years since the turn of the 21st century have been drought years in the state. The year 2026 proved particularly severe as Karnataka recorded a record 35% rainfall deficit, with 551 millimetres of rainfall between June 1 and September 30 across 30 districts and 209 taluks. Reddy added that 2026 is an El Niño year, which historically coincides with nearly 60% of Karnataka's drought years and limits cyclone impacts.

Program Operation And Science

Karnataka previously carried out cloud-seeding operations in 2003, 2017, and 2019. The current initiative, named the Karnataka Emergency Cloud Seeding Programme 2026, is undertaken by the Water Resources Department and supported by a monitoring committee alongside a technical advisory and evaluation committee. Members include officers from the Karnataka State Natural Disaster Monitoring Centre, Karnataka Neeravari Nigam Limited, and the Rural Development and Panchayat Raj Department. S.T. Aruna, chief scientist at the CSIR-National Aerospace Laboratories in Bengaluru, explained that cloud seeding disturbs a water-heavy cloud to produce rainfall, relying on mixed-phase clouds where ice crystals and supercooled water interact through the Wegener-Bergeron-Findeisen process. While methods range from ground generators to artillery shells, the most common approach in India uses a light aircraft like a Cessna fitted with flare racks to release aerosols at cloud bases.

Evaluation And Monitoring Challenges

Calculating cloud-seeding efficiency remains difficult because distinguishing induced rain from natural rainfall is debated. Thara Prabhakaran, a scientist at IITM Pune, noted that evaluation relies on surface rain gauges assuming the water came from seeded clouds. A 2019 IITM study on Karnataka's 2017 Project Varshadhare reported an estimated average rainfall enhancement of 27.9% above natural levels. Another IITM study from the CAIPEEX programme found an 18% average increase over a 100-square-kilometre area in Solapur, Maharashtra. However, Madhavan Nair Rajeevan, a former director of IITM Pune, questioned whether an 18% surplus suffices for severe water stress and stressed that artificial rain cannot be generated without adequate cloud development. Critics also pointed out that unlike past operations using three dedicated Doppler weather radars, the current programme depends solely on pre-existing radars in Goa, Hyderabad, and Chennai.

Context

Cloud seeding is often deployed by governments as an emergency intervention during severe agricultural distress, even though its scientific efficacy under specific late-monsoon conditions remains heavily debated by meteorologists. The technique requires precise atmospheric dynamics, specific cloud phases, and robust real-time radar tracking to target viable cloud formations successfully.