Amid the driest autumn in half a century, Iran has launched large-scale cloud seeding operations in an effort to trigger rainfall and ease the country’s deepening water crisis, according to state-run news agency IRNA.

The National Weather Forecasting Center of Iran’s Meteorological Organization reports that precipitation levels have dropped by 89% compared to the country’s annual average. This dramatic decline makes this autumn the driest season recorded in the past 50 years.

Cloud seeding efforts are already underway near Lake Urmia using specially equipped aircraft. Just two decades ago, Urmia was the largest lake in the Middle East, supporting a booming tourism-driven economy. Today, the lake is rapidly drying up, turning into a salt flat, with once-busy boats rusting on its parched bed.

Cloud seeding operations will soon expand to Iran’s East and West Azerbaijan provinces, which border Lake Urmia and share a frontier with Azerbaijan.

The technique, used in Iran for years, involves dispersing chemical agents into the atmosphere to encourage rainfall. But amid a prolonged drought now entering its fifth consecutive year, the method has become increasingly vital. Reservoirs are rapidly drying up, authorities are enforcing water usage restrictions, and citizens are being urged to conserve every drop.

According to state broadcaster Press TV, the water shortage is now causing concern even in Iran’s largest urban centers, including the capital, Tehran.

Mohammad Mehdi Javadian-Zadeh, head of the National Cloud Seeding Research Center, said the operations will continue until mid-May, using both aircraft and drones if weather conditions allow. He stressed that Iran’s naturally arid climate leaves cloud seeding as one of the few available tools to increase precipitation.

Cloud seeding is a type of weather modification that aims to change the amount or type of precipitation, mitigate hail, or disperse fog. The usual objective is to increase rain or snow, either for its own sake or to prevent precipitation from occurring in days afterward. Cloud seeding is undertaken by dispersing substances into the air that serve as cloud condensation or ice nuclei. Common agents include silver iodide, potassium iodide, and dry ice, with hygroscopic materials like table salt gaining popularity due to their ability to attract moisture. Techniques vary from static seeding, which encourages ice particle formation in supercooled clouds to increase precipitation, to dynamic seeding, designed to enhance convective cloud development through the release of latent heat. Methods of dispersion include aircraft and ground-based generators, with newer approaches involving drones delivering electric charges to stimulate rainfall, or infrared laser pulses aimed at inducing particle formation. Despite decades of research and application, cloud seeding's effectiveness remains a subject of debate among scientists, with studies offering mixed results on its impact on precipitation enhancement.