Over the past few days, the air quality in Delhi and its surrounding regions has significantly deteriorated, causing immense problems for residents and enveloping northern parts of India in a toxic haze. As of 5 pm on Wednesday, the air quality index (AQI) in Delhi stood at a ‘very poor’ level of 398. To address this alarming issue, the Indian Institute of Technology (IIT) Kanpur has put forward an innovative solution – the concept of “artificial rain” through cloud seeding. This ambitious project has been in development since 2018, with trials conducted in July of this year after securing the necessary permissions from government authorities, including the Directorate General of Civil Aviation (DGCA).
Manindra Agrawal, a professor in the computer science and engineering department at IIT Kanpur, is the driving force behind this groundbreaking project. He explained that artificial rain could provide temporary relief for up to a week to the residents in the National Capital Region (NCR) who are grappling with poor air quality.
What is Cloud Seeding?
Cloud seeding is an artificial technique employed to enhance rainfall by introducing specific substances into clouds. This method serves various purposes, including mitigating the impact of droughts, preventing forest fires, increasing precipitation, and improving air quality.
During cloud seeding, various chemicals like silver iodide, potassium iodide, and dry ice are released into the sky, typically using airplanes and helicopters. These chemicals attract water vapor, leading to the formation of rain clouds. The process generally takes about half an hour to induce rainfall.
Cloud seeding techniques can be categorized into two main types. Hygroscopic cloud seeding aims to expedite the coalescence of droplets in liquid clouds, leading to the formation of larger droplets that result in precipitation. This method typically involves dispersing salt particles at the cloud’s base. The other technique, glaciogenic cloud seeding, focuses on inducing ice production in supercooled clouds, triggering precipitation. It requires the release of efficient ice nuclei, such as silver iodide particles or dry ice, into the cloud, thereby initiating heterogeneous ice nucleation.
Implementation Challenges
Implementing artificial rain through cloud seeding requires obtaining various approvals, including those from the DGCA, the Ministry of Home Affairs (MHA), and the Special Protection Group, responsible for the Prime Minister’s security, to allow aircraft to fly over the national capital. Additionally, the success of this innovative approach hinges on specific meteorological conditions, including the presence of moisture-laden clouds and suitable wind patterns.
While cloud seeding shows promise as a temporary solution to mitigate air pollution in Delhi, it is vital to continue exploring comprehensive, long-term measures to address the root causes of the issue and ensure sustainable improvements in air quality for the region’s residents.