The UAE is moving at the forefront of weather modification science in an attempt to counter its arid climate and water shortage issues
On 9th March 2016, the UAE experienced 287 millimetres of rain across Al Ain and Dubai.
It is said to be the highest recorded rainfall in a single day since the country started recording such data in 1977.
For a desert country with predominantly dry weather, the torrential shower was quite a surprise, especially to those living in the affected areas.
Rumours were rife: What caused the phenomenon? Was it climate change?
According to the National Centre for Meteorology and Seismology (NCMS), it was actually a combination of nature and science, with cloud seeding playing a major role in triggering the record-breaking downpour.
Up in the clouds
Cloud seeding is not a new practice in the UAE. Since the first project in February 1982, which covered a 7,000km stretch of desert, NCMS has been gradually carrying out operations throughout the country since the early 2000s.
“The goal is of course to extract more rain from the clouds, and we’ve continuously conducted many studies to validate the benefits from these operations,” Omar Al Yazeedi, director of research, development and training at NCMS, tells us.
Cloud seeding is a form of weather modification that enhances the amount of precipitation in clouds.
Here in the UAE, Beechcraft C90 King Air planes are deployed to spray the atmosphere with salt crystals mixed with potassium, sodium chloride and magnesium.
These particles then form ice crystals that are too heavy to remain suspended in the air, causing them to fall and melt on the way down to become rain.
For the crew at NCMS, starting the process by monitoring the clouds through satellite and radar images can start as early as 4am.
Upon determining the type of clouds (usually cumulus) with the best rain potential, the team then radio pilots on standby in a base in Al Ain to carry out the actual operation.
A single operation involves around three or four people working on the ground and in the air, and may take between two to three hours to be completed, depending on the number of targeted clouds.
“The window for this operation is very small. The clouds could develop then dissipate in less than an hour so we have minimum seeding time,” explains Omar.
“That’s why we move our hangar to Al Ain so instead of losing the time during the flight, we’re closer there in the mountains where the activity happens.”
He continues, “We are using aircrafts because it gives us more control. In some countries they’re using rockets, but we’re not using that for safety reasons.”
That said, the operation is not limited to Al Ain as the planes go around the country wherever there are suitable clouds detected by the radars.
Cloud seeding has various purposes: Some countries resort to it to suppress hail formation to save potential crops and property from damage, dissipate fog, alter hurricanes and even decrease chances of lightning.
For the UAE, it is a means to boost rain to benefit farmlands, increase water supply and recharge underground water like in wells – all of these help ease the effects of long dry spells that the country naturally experiences.
It is estimated that cloud seeding operations can boost rainfall in the country by anywhere from ten to 35 percent.
“We do monitoring and cloud seeding operations all year round,” says Sufian Farrah, meteorologist and cloud seeding expert at NCMS.
“But the middle of July and September is when we do more operations, about four days a week, because there’s a higher frequency of amenable clouds that are likely to react to these operations during the summer season.”
The agency conducted 242 cloud seeding operations in 2017 alone, an increase from the 177 in 2016.
As to whether the method might carry potential environmental risks and long-term weather disruptions, Sufian says: “To be clear, we’re not creating rain but just enhancing or helping speed up the process for these rain-carrying clouds.”
He also says that the after-rain effects can help cleanse the atmosphere.
For all its hype, cloud seeding is not a perfect science and experts continue to debate on its effectiveness in actually boosting rain output.
Even NCMS admits that it has no way of accurately telling whether a rainfall is directly caused by its cloud seeding operations or just a natural occurrence. What’s more, not all cloud seeding procedures yield the expected rain results, making it a hit or miss operation.
But that’s what motivates the agency to do further studies and research to fully grasp the complex science behind it. Because although cloud seeding has been around since the 1940s, there have only been minor improvements both scientifically and technologically over the years, according to Omar.
“The advancement in this area has not been much. This was the same formula years ago. Nobody enhanced it because it’s a very expensive endeavour,” confides Omar.
“For one, all the experiments have to be done in the air and the clouds, so that alone makes it challenging for researchers.
“You can’t simply simulate theories by computer; you have to be actually up there with aeroplanes, satellites and radars to test and determine results.”
To help advance the science, the government launched the UAE Research Program for Rain Enhancement Science initiative in 2015. The aim is to gather innovative projects from scientists in the field of rain enhancement from all over the world, with the winning ideas obtaining a grant of $5 million (AED 18 million) to further work and improve on the concepts for a period of three years; the next batch of awardees will be announced this month.
By gathering the best minds and ideas, the UAE government and NCMS are hoping to come up with noble techniques and studies to complement the current procedures.
“We’re looking at various elements and we want to have better, reliable materials that can be applied,” says Omar.
“Our objective is to have better knowledge of all the facets: understanding better cloud characteristics, the precipitation process, potential technology and new formulas that we can use during actual operation.
“For example, we’re thinking of the idea on how to make more clouds later on so let’s make the scientists do more research about this to know the probability.”
Early this year, a UAE research team led by Dr Linda Zou, professor at Masdar Institute of Science and Technology, who is also one of the grant winners, applied for a US patent for the team’s cloud-seeding method using nanotechnology properties to increase cloud condensation.
By doing all these, the UAE is not only looking to address its own water sustainability targets but to also take the lead in paving the way for other countries to follow suit to meet their own objectives.
“There are some experiments not just in the UAE and the region but worldwide,” Omar continues. “A lot of countries are doing cloud seeding for precipitation purposes or the other way around.
“I think there are more than 150 related projects done by more than 55 countries in the past. So we’re trying to move the science forward not just in the country but worldwide.”
WORDS Ferdinand Godinez