Officials in the Environment Ministry have approved a project led by scientists at the Indian Institute of Technology (IIT) Kanpur to induce artificial rain via cloud seeding to clear smog in Delhi.
However, the success of the endeavour depends on the presence of a minimum quantity of rain-bearing clouds — so far none in sight — over Delhi.
The project will have an aircraft fly into the clouds and inject silver iodide, which will lead to the formation of ice crystals that will make the clouds denser, cause them to condense into rain and settle atmospheric dust enough to clear the sky.
While cloud seeding is not new to India — Karnataka, Andhra Pradesh and Maharashtra have experimented with it in limited trials through the decades to address droughts — this is the first time it will be tried during the winters, when there are barely enough monsoon clouds on the horizon.
“If there are enough clouds, we will surely go ahead with this,” Ministry of Environment, Forests and Climate Change Secretary C.K. Mishra told The Hindu on the sidelines of a conference.
Researchers at IIT-Kanpur will use an aircraft of the National Remote Sensing Agency, an ISRO-affiliated body for the exercise. The Indian Meteorological Department (IMD) will provide forecasts on the likelihood of conducive clouds.
“There is a western disturbance forming in Jammu & Kashmir…. that will not be enough as we need clouds in the plains. Such seeding is routine in Russia and other cold countries, when they need to disperse fog at airports…In this case, we need to create clouds. It is a completely different challenge,” said IMD Director-General K.J. Ramesh.
The Indian Institute of Tropical Meteorology (IITM) and the IMD have since the past four years been conducting experiments with cloud seeding in Maharashtra during monsoon to examine if it actually works and, if it does, to evolve guidelines on how these ought to be conducted.
“In four years, we have had 30 successful instances of seeding,” Mr. Ramesh said, adding that other than providing forecasts, the the IMD is not involved in the IIT-Kanpur initiative.
However, another meteorologist in the government expressed reservations.
“You could do cloud seeding to clear out skies over an area of a football field but I doubt you can pull it off in a region the size of Delhi-NCR,” the meteorologist said.
Delhi’s Air Quality Index on Tuesday was in the ‘very poor’ category. A forecast by the IIT-M said while winds are expected to pick up on Wednesday, it will not translate into substantial improvement in air quality.