Cloudseeding explained: The business of rainmaking
Cloud seeding could provide a sustainable solution for water security in the long run
The UAE has experienced a long spell of wintry conditions in the past week, particularly on Sunday, when rain showers persisted throughout the day.
There is reason to believe that these conditions resulted from the country’s cloud seeding programme, which was initiated in the late 1990s and aims to address the pressing challenge of water security.
Dr Ahmed Habeeb, a meteorologist and expert at the National Centre for Meteorology and Seismology, said that 58 cloud seeding operations had been carried out since the start of the year. More than 20 millimetres of rain fell over Al Faqa, on the Abu Dhabi-Dubai border, on Sunday. Dr Habeeb said that “cloud seeding is a way to enhance the amount of precipitation that falls from the clouds and helps generate 10 to 30 per cent more rain.”
But what is cloud seeding? How is it conducted? And does it have its limitations?
Cloud seeding, or weather modification, is the application of scientific technology to enhance a cloud’s ability to produce precipitation.
Its roots can be traced back to the 1940s, when scientists and researchers at General Electric realised that flecks of dry ice converted supercooled water droplets into ice crystals.
Some dispute this narrative of events, however, and champion the efforts of Charles Hatfield some 30 years earlier. He is said to have used a “secret formula” to make it rain on demand in 1915 and end a drought in San Diego.
When supercooled droplets of water – those that are still liquid but are at a temperature below the usual freezing point – form ice crystals, these crystals are too heavy to remain in the air, and so they fall, often melting on their way down to form rain.
Laboratory trials were successful in demonstrating the properties of various compounds in certain conditions and eventually led to cloud seeding trials.
The “seeding” can be done either from the ground or from the air.
In addition to increasing precipitation, cloud seeding can, in some territories, mitigate hail damage and protect crops, homes and other property, reducing the economic cost of disastrous storms. It can also be used to disperse ground-based clouds or fog.
However, despite its apparent success, cloud seeding still has its limitations and can sometimes be ineffective.
Research has shown that certain clouds or stages of cloud development are not susceptible to seeding.
But the UAE is driving research to develop it further.
We have the UAE Rain Enhancement Programme award. And in February, a research team filed a provisional application for a patent after developing a cloud seeding technique involving coating a pure salt crystal with a thin coating of titanium dioxide to enhance the condensation process.
Rain enhancement could provide a way for the future. The next step is to build more reservoirs and dams to capture it.
Updated: March 2, 2017 04:00 AM