In the skies above the United Arab Emirates, pilots fly propeller planes into storm clouds, releasing salt particles in hopes of coaxing rain from the dry desert air. This process, known as cloud seeding, has become a cornerstone of the UAE's efforts to address its deepening water scarcity.

The Gulf state, which receives less than 100mm of annual rainfall and has limited natural groundwater, spends millions each year on cloud seeding missions to boost freshwater supplies.

The effort is part of a broader climate change adaptation strategy, according to Alya al-Mazrouei, director of the UAE Research Program for Rain Enhancement Science (UAEREP), who spoke with the Financial Times on the initiative.

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Flying into clouds: How rain enhancement technology works

According to the report, cloud seeding involves firing potassium chloride or salt particles into convective clouds, which are formed by rising warm air. These particles help the water vapour in the clouds to coalesce into raindrops. When conditions are favourable, rainfall can begin within 15 minutes.

The UAE’s programme currently employs 10 pilots and four Beechcraft King Air C90 aircraft, ready to launch whenever suitable clouds form. “Whenever we have the opportunity… we don’t usually miss any opportunity,” Mazrouei told Financial Times.

Each hour of flight costs around $8,000, and the programme averages 1,100 flight hours annually, amounting to nearly $9 million. Despite the high cost, officials argue that cloud seeding delivers water at a lower cost per cubic metre than desalination, the UAE’s primary water source.

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Desalination vs cloud seeding: Cost and effectiveness

While desalination remains essential for the UAE’s drinking water needs, it is energy-intensive and costly. Cloud seeding offers an alternative source of freshwater with a potentially lower environmental and financial footprint, especially when rainfall can be naturally enhanced.

A 2021 peer-reviewed study linked to the UAE's programme found that rainfall increased by an average of 23% in areas where cloud seeding was conducted. Another study by the National Centre of Meteorology (NCM) in 2023 estimated that cloud seeding could enhance harvestable water volumes by 84 million to 419 million cubic metres annually.

Still, experts caution that measuring precise results is difficult. “It’s not quite a precise return on investment,” Orestes Morfín, a water resources expert with the Climate and Water Initiative in Arizona, told Financial Times.

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Cloud seeding under scrutiny amid climate change and storms

As the UAE ramps up its use of rain enhancement technology, the method faces growing scrutiny. Some critics have raised concerns about the environmental impact of the chemicals used and the unintended consequences of artificially altering weather patterns.

A devastating storm that struck the UAE last year led some to blame cloud seeding for the extreme weather, though the NCM denied conducting any missions at the time. Scientists pointed instead to the combined effects of climate change and urbanisation as the more likely causes of the record rainfall.

“Cloud seeding is seen as an additional potential tool for boosting water supply,” Morfín told the Financial Times, noting that the process is also used in other countries to mitigate hailstorms or snowpack loss.

Despite debate around its accuracy and outcomes, the UAE continues to expand its cloud seeding initiatives. The country has also invested $22.5 million in research grants to improve rain enhancement technology.

Mazrouei emphasised to the Financial Times the UAE’s commitment to the effort. “Although success is not guaranteed,” she said, “the opportunity to improve water availability makes the investment worthwhile.”

While some outcomes remain difficult to quantify, officials and scientists alike view cloud seeding as one piece of the puzzle in addressing water scarcity in the UAE, a country where every drop counts.