Cloud Seeding Cannot Alleviate Air Pollution

Cloud seeding projects are primarily aimed at increasing rainfall in Iran and cannot directly help alleviate air pollution, said an official at the National Cloud Seeding Research Center. 

However, the method had been lately proposed to help improve Tehran's air quality. 

Farid Golkar, the head of NCSRC, asserted that the technique can amplify the positive effects of rainfall in improving air quality but maintained that the idea is not practical, as the capital is not currently experiencing precipitation, ANA reported. 

"Besides, it is not easy to obtain flight permits in Tehran due to its busy air traffic and high peaks, as well as a multitude of no-fly zones," he said. 

Golkar added that Tehran's climatic conditions are unique and directly affected by pollutants that can even change the natural process of rainfall. 

"This makes the implementation of cloud seeding difficult in the metropolis," he said.

The project was implemented in Tehran two years ago, but never again. 

Based on calculations in that year, a single sortie, including aircraft's rent and fuel, insurance and seeding material, cost 1.2 billion rials ($31,400).

"It's probably more expensive now," he added.

-- Funding Challenges

The center currently has rented two aircrafts for the purpose, all the costs of which have so far been paid by the airline company, which he did not name. 

"We're not sure how long we can keep trying if we don't receive a budget," he said.  

Morteza Eftekhari, the head of Iran's Water Research Institute, had earlier complained about the lack of funds and said out of the 100 billion rials ($2.5 million) earmarked in the budget, only 12 billion rials ($308,000) were allocated to the project last year.

Cloud seeding, a form of weather modification, is a way of attempting to change the amount or type of precipitation by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the cloud's microphysical processes. 

Like other forms of weather modification, cloud seeding has drawn its fair share of criticisms. The practice has been controversial since it was invented in 1946 by American chemist Vincent Schaefer. 

“There’s little dispute that if you can actually get the seeding material inside the clouds, it will enhance precipitation,” Dan Breed, a scientist with the US National Center for Atmospheric Research, was quoted as saying by Bloomberg in an article published in 2015. 

“The question is, by how much? Just as it’s hard to predict the weather, it’s hard to really know if you’ve made it rain or not."