Modification of clouds was first discovered in 1946 by American chemist Vincent J. Schaefer, which is now termed cloud seeding.
In recent years, cloud seeding has exploded in popularity across the Middle East to secure water resources. While the effectiveness and complications of cloud seeding are debatable, UAE and Saudi Arabia have large-scale cloud seeding research programs and have invested millions in cloud seeding efforts.
“Cloud seeding is all about using a suitable aerosol material like common salt or silver iodide and injecting them at the base of clouds so that more and possibly larger cloud droplets can form. When there are enough droplets, they can combine to form bigger droplets that can eventually fall as rain,” says Dr Sagar Parajuli, a research scientist at King Abdullah University of Science & Technology in Saudi Arabia.
Since its discovery and continual trials, cloud seeding has been used globally to combat water insecurity, including in China, and the US.
According to the National Centre of Meteorology (NCM), UAE is one of the first Arabian Gulf countries to use cloud seeding. It was first initiated in the 90s and has now been established as UAE Rain Enhancement Program (UAEREP).
“Cloud seeding operations aim to increase the amount of rainfall and its duration. The rainfall derived from rain enhancement is used in restoring or recharging the aquifers and groundwater storage,” says Dr Youssef Wehbe, Project Manager at NCM.
Although UAE uses desalination to deal with water insecurity, cloud seeding has proven to be more cost-effective.
Explaining the methods used in the region, Wehbe describes cloud seeding as “a technique of weather modification that takes place at the base of the cloud using hygroscopic materials.”
Recently, many renowned local and international scientists and researchers presented their investigations on cloud seeding in a webinar series, Rain Enhancement Hub, launched by NCM and organized by UAEREP.
In the webinar, Noor Al Shamsi, weather forecaster at NCM, highlighted the methods used by the NCM and presented the progress report of cloud seeding in UAE. She explained the two types of seeding methods: dynamic seeding method (burn flares at the updraft of the cloud) and static seeding method (flares deposited at the top of the cloud).
According to Al Shamsi, the dynamic seeding method is used in the UAE because it’s most suitable for the region. Furthermore, factors such as correct timing (as soon as the cloud appears), correct location (updraft location), and the number of burnt flares (more is better) are all vital in ensuring the success of the seeding operations.
A PREMATURE TECHNOLOGY
However, as cloud seeding yields artificial rain, the risks should also be considered. Parajuli recently presented his research, Direct and Indirect Effect of Dust on Rainfall, highlighting the possible side-effects that cloud seeding may have.
“[Cloud seeding] is a premature technology. There are several risk factors associated with it,” he says. For example, we might seed clouds in a certain location, and it may rain in another area. Or it may trigger incessant rain that could cause flooding. “The main concern of cloud seeding is that we might be unable to control what happens in the atmosphere with our intervention. A small trigger can cause big effects because several variables interact in the atmosphere.”
For example, aerosols also reflect sunlight and absorb heat; of course, the seeded clouds further affect radiation balance. “These changes can disturb regional wind and weather patterns, leading to unintended consequences. Rainfall is indeed a complex process — we still do not fully understand what particular factors trigger rainfall,” he adds.
Emphasizing that cloud seeding in UAE is safe, Wehbe says the aerosols used are “environment-friendly salts.”
According to Dr Mohammad Mahmoud, Director of the Climate and Water Program at the Middle East Institute, the cloud seeding program in UAE, and other GCC countries, is at a “budding” stage. Any cloud seeding program’s “feasibility and viability” must be jointly funded and worked in partnership with other countries.
Since the Arabian Peninsula is drought-prone, he says the technologies used for cloud seeding are different from those used for years in the US.
Meanwhile, Dr Edward Graham, a meteorologist at the University of Highlands and Islands, UK, says, “cloud seeding cannot saturate the air nor generate clouds, nor disperse them/evaporate them. It is only about making clouds more ‘efficient’ at rainfall. So the weather pattern has to be one where it is likely to rain already, which is rare enough in the UAE”.
Although UAE’s cloud seeding program is at an early phase, according to experts, the continual research and progress in its programs and collaboration with countries such as Saudi Arabia can ensure a positive future in terms of increasing water security in the region.
One such advancement in the cloud seeding study is the introduction of artificial intelligence (AI) research and geospatial mapping of the weather.
Deploying AI, NCM plans to achieve enhanced precipitation forecasts to get better results from such initiatives. The algorithms measure precipitation in the environment to tell if there’s enough humidity for cloud seeding operations to be successful.
AI processes satellite observations, ground-based weather information, rain gauges, and numerical predictions to determine the best time and place for cloud seeding.
Earlier, traditional satellites were used that lacked the required resolution to monitor rainfall events. Bayanat, an AI-powered geospatial intelligence company, has provided SAR (Synthetic Aperture Radar), an accurate cloud mapping technology, to better predict the ideal factors for seeding the clouds.
Highlighting the importance of AI in cloud seeding, Dr Markus Mueller, Engineer and AI manager at Bayanat, says, “AI can play a role. The relationships between all these climatic variables are extremely complex, and the physics is [also] complicated. Quite often, we don’t understand how they relate to each other, so machine learning can play a role in figuring out how and what kind of relationship exists, leading to a better physical understanding at the end of the processes.”
Wehbe is optimistic about the rain enhancement methods used in the region. “NCM has laid a solid foundation for future research in rain enhancement science. It will ensure the continuity of rain enhancement science while employing the latest technologies such as AI and machine learning to break new ground in cloud seeding to enhance the water supplies.”
“More specifically, further projects are underway to deal with the creation of artificial updrafts to induce rain; targeted observation and seeding through unmanned aerial vehicles; and advanced experimental-numerical approaches to rain enhancement,” he adds.
There has been much research done around the world on cloud seeding for over 70 years. “The results show that cloud seeding probably, albeit marginally, creates greater precipitation on order of a few percentage points, but each case is unique and cannot guarantee positive results on any single occasion,” says Graham.
Discovery and usage of any new technology is a gamble, as it brings various risks and benefits.
Given the region’s water scarcity and an evidential increase in the overall rainfall with the help of cloud seeding, one can’t ignore the significance of cloud seeding operations.