Artificial Rain by IITK

On June 22, IIT Kanpur successfully conducted an experiment for cloud seeding. The experiment was a success owing to the valuable contribution of numerous people from IIT Kanpur, including Dr. Manindra Agrawal, Dr Mainak Das, Dr Deepu Philip, and their associates spanning multiple departments with diverse backgrounds. With the approval of the Directorate General of Civil Aviation (DGCA), the objective of the test was to successfully test all the equipment required for cloud seeding during an in-flight environment. To better grasp the intricate machinery behind this project, we spoke to Dr Manindra Agrawal in an exclusive interview. 

Vox: What exactly was the project and the intent of this experiment?

Dr. Manindra Agrawal: The project is on the concept of artificial rain by a method called cloud seeding. This experiment was conducted to check if the systems required for cloud seeding operate well and collect the relevant data. An important clarification I would like to provide is that ‘Cloud seeding was successfully achieved’ is incorrect. The reason is that the intent was to check the systems and collect data, not to seed the cloud and make it rain. In any case, that day from the night, it was already raining, so there was no way even to find out if we had succeeded, even if we had tried. Some media reports are saying otherwise, but that’s not correct. 

Vox: How did this project start?

Dr. Manindra Agrawal: The concept of cloud seeding was taken up five years ago and has been wholly led and funded by the institute. The Uttar Pradesh government had shown interest earlier, but things slowed down due to covid. It was decided to use IITK’s own Cessna aircraft for this purpose, for which collaboration with the US-based company ‘Cessna’ was sought to facilitate instrumentation and equipment fitting on the plane. However, the progress was halted for over two and a half years due to the outbreak of the Covid-19 pandemic. 

During this time, efforts were focused on obtaining validation from the Directorate General of Civil Aviation (DGCA), which recently took place in the last six months. This project is estimated to cost about one crore, which the institute has entirely borne up to this point. The recent flight marked a significant milestone as it was the first time flares were attached and fired to collect data on flight behavior. DGCA members were present to observe and gather relevant information. The data will now undergo analysis, and once the DGCA confirms its accuracy and safety, the aircraft will be flown according to the project’s requirements. The primary objective of the flight was to assess firing and aircraft dynamics, with a particular emphasis on stability.

Vox: How is cloud seeding done?

Dr. Manindra Agrawal: This technology involves salt (typically AgI). Particles of diameter 1-10 microns are sprayed onto the existing clouds. With the introduction of these microparticles, condensation starts, resulting in the increased weight of these particles and subsequent precipitation. The mixture is released into the clouds with the help of flare attachments. These flares contain a salt mixture and gunpowder. They expand and spray the mixture into the air when fused. An additional advantage of flares is that the airplane can fly below the clouds, whereas the hot air surrounding the particles can rise up to the clouds, resulting in a safer flight. Cloud seeding is a well-established technology in the Middle East.

Vox: How does this project contribute to cloud seeding technology?

Dr. Manindra Agrawal: While cloud seeding is an established technique, IIT Kanpur furthered the research with its unique approach. The institute experimented with various salts, yielding promising results. Considering the potential harm associated with large quantities of silver iodide, the institute explored alternatives in common salt of different granularities. As a result, a mixture with a reduced amount of AgI was successfully produced. Dr Mainak Das and his lab played a pivotal role in achieving these breakthroughs.

Vox: What is the Environmental Impact of this project?

Dr. Manindra Agrawal: Cloud seeding allows for the redistribution of rainfall in a region while the total amount of rain remains relatively constant. However, careful consideration must be given to avoid concentrating all the rainfall in one area at the expense of the others. While the potentially harmful effects of the composition mixture require thorough testing, the high dilution of the salt mixture suggests negligible hazardous impact.

The project is designed to serve two purposes. 

• First, it can be beneficial in regions experiencing little or no rainfall despite the presence of clouds. 

• Second, in large cities with high pollution levels during winter, cloud seeding can temporarily alleviate pollution through rainfall.

Vox: What lies ahead for cloud seeding?     

Dr. Manindra Agrawal: Obtaining full approval from the Directorate General of Civil Aviation (DGCA) is considered the first crucial step in the project to ensure a perfect setup. Our team is diligently gathering and providing all the necessary data to satisfy the requirements of the DGCA, aiming to secure their final approval. Meanwhile, we’ll initiate discussions with some government entities. We are not interested in doing this on a commercial basis. Notably, there is already growing interest from various state governments regarding the project. The team anticipates that this approval could be granted within the next month or two if everything progresses as planned. Fortunately, this timeframe aligns well with the upcoming rainy season, making it less critical to perform cloud seeding immediately. Once the approval is obtained, the team intends to conduct further trials to assess the outcomes. The team is optimistic and eager to see the results of these trials.

So, is climate control within our grasp? Certainly not; we are still far from causing artificial rain, as mentioned by Dr Manindra Agrawal, but to recapitulate the essence of this project, we are definitely looking forward to a bright future ahead of us. This success is yet another example where IIT Kanpur has taken a significant step towards achieving solutions to real-life problems faced by the Indian Subcontinent through dedicated effort and cutting-edge research on a collaborative front. Despite facing many obstacles in the path of this project, IITK has achieved a remarkable feat by managing a project of this magnitude solely on its own. We will eagerly look forward to the successful large-scale deployment of this project soon. Congratulations, and good luck to the team!