Zawya speaks to the three scientists whose ideas have received $5 mln via this year’s Rain Enhancement Programme.
By Nada Al Rifai, ZAWYA
As the United Arab Emirates navigates the path to raise its water security levels, the arid Gulf country is funding a number of new research ideas aimed at boosting rainfall.
The UAE’s Rain Enhancement Programme this year awarded a $5 million grant to scientists from the United States, China and Russia to fund research aimed at enhancing rainfall. The grants were awarded under the third cycle of the programme, which, since its foundation in 2015, has received proposals from more than 1,220 researchers in 68 countries.
The UAE’s efforts to enhance rainfall, however, dates back to the 1980s. (Read more here).
“In February 1982, the Abu Dhabi Municipality carried out the country’s first cloud seeding attempt, and it is was conducted by an American aircraft using silver iodine at that time,” Sufian Farrah, a cloud seeding specialist at the UAE National Center of Meteorology (NCM), told Zawya at an interview in January during Abu Dhabi Sustainability Week.
Water security is a pressing issue worldwide and the UAE is looking at ways to address shortages. Around 1.6 billion people live in areas with absolute water shortages, according to the World Bank, which estimates that this figure is set to rise to 2.8 billion people by 2025.
NCM’s Farrah states that cloud seeding operations can currently improve rainfall in the UAE by 10 to 15 percent in turbid atmosphere and 30 to 35 percent in a clear one. So the amount of rainfall increased artificially in the UAE is no more than 35 percent of the naturally occurring amount.
The UAE conducted 242 cloud seeding operations last year, with each operation taking about three hours, according to Farrah. He said that 98 of these were even carried out during the hot summer months – from the beginning of June until the end of September.
The UAE owns six aircraft dedicated to cloud seeding operations, with a hangar in Al Ain airport. The most frequent occurrences of clouds suitable for seeding take place in the more mountainous Eastern region.
A greener resource
Rainfall enhancement is considered to be a cleaner method for boosting water security levels in the region than desalination plants, some of which use pollutants, and which increase the water salinity of the seas, according to NMC’s Farrah.
“The cost effect between rainfall enhancement through cloud seeding and expelling out fresh water from desalination is about 1 to 60 ratio, so it is also cheaper,” said Dr Ali Abshaev, one of the three winning scientists to secure a grant via this year’s rain enhancement programme.
Dr Abshaev, an associate professor at the Hail Suppression Research Center in Russia, told Zawya during an interview in January during Abu Dhabi Sustainability Week that “rain enhancement is the only way to have additional water on a wide scale, because with desalination, or other types of technologies, you cannot obtain more water (across) areas (with) several hundred or thousand square kilometres. Yet, it is possible with rain enhancement.”
He continued: “For example, in my place where I come from (in) Russia, the dimension of the clouds is about 30 kilometres in diameter, so the area affected by the rainfall is really huge, especially with clouds moving.”
In the UAE, however, most clouds have a much narrower range, with a radius of 5-8km and a lifetime of around 45 minutes.
Dr Abshaev, who is also head of the Weather Modification Laboratory at the High Mountain Geophysical Institute, part of the Russian Hydrometeorological Service, is receiving funding from the UAE’s programme for research into stimulating rainfall in the absence of clouds through artificial cloud creation.
Lack of foresight
So why isn’t more invested into cloud seeding if it is a better way to increase water supplies?
The difficulty is that conditions do not occur repeatedly, according to Dr Eric W. Frew, another of the three winning scientists of a UAE research grant. He is an associate professor in the Ann and H.J. Smead Aerospace Engineering Sciences Department from the U.S.
“The problem is that you can’t predict in advance when the conditions will be there, and you can’t rely that the conditions will always be there. There is a natural capacity in the environment, but that is not reliable enough,” Dr. Frew told Zawya during Abu Dhabi Sustainability Week.
“The most challenging aspect of cloud seeding is that you can’t seed any clouds in the atmosphere… only a certain type of clouds that react to the material flared into them,” he added.
Another problem in the UAE is that there is a lot of fluctuation in rainfall levels, according to NMC’s Farrah.
“Last year, it was 107 millimetres, while it was around 97 the year before, around 45 a year earlier, and 136 the year before. So it is difficult to assess by how much we intend to increase the rainfall,” Farrah noted.
Weather trends changing
According to the World Meteorological Organisation, 56 countries worldwide engaged in cloud seeding in 2016. Farrah said that some of these are for rainfall enhancement, but others are working on hail suppression to mitigate the damage caused by large hail stones.
“Operational wise, China is the country that conducts the most weather modification and rain enhancement operations in general,” said Dr. Lulin Xue, chief scientist at Hua Xin Chuang Zhi Science and Technology.
Dr. Xue, another of the scientists to receive grant funding under the Rain Enhancement Programme at Abu Dhabi Sustainability Week, told Zawya during the event that weather modification “is almost a daily operation in the whole country”.
“If the conditions are good on that day, we do it. So it is happening at a massive scale in China in terms of operations,” Dr. Xue said.
In addition to working on cloud seeding projects in Saudi Arabia and the U.S., Dr. Xue is also a member of the Beijing Weather Modification Office advisory panel.
The project for which he has received funding aims to explore the impact of cloud seeding on rainfall in the UAE over a 10-year period through seeding simulations.
In the U.S, Dr. Frew is seeking to develop an unmanned aircraft system with sensors to target clouds that are suitable for seeding. His project also aims to explore effective delivery of seeding material into clouds. He said that the lifetime of clouds in the UAE is currently just 45 minutes during summer.
“The drones are intended to make the lifetime of the clouds longer, to be more responsive to the clouds forming, and to better understand about these clouds,” Dr Frew told Zawya.
“It cuts down on the time wasted and allows quicker decisions within a limited timeframe,” he said.
If a normal aircraft is used to seed clouds there are limitations around manoeuvrability and the amount of time spent in the air when compared to a drone.
“With the drones’ technology, we are hoping we can reach the targeted area quicker, and stay there longer,” said Dr Frew, who is also director of the Autonomous Systems Interdisciplinary Research Theme at the College of Engineering and Applied Sciences at the University of Colorado.
“For our project, we are taking advantage of some of the breakthroughs in autonomous technology for drones and umanned aircrafts, and looking to bring those into the area of rain enhancement,” he said.
“We are making smaller sensors that can go on the aircraft, and then we will use those, combined with artificial intelligence, to be able to make faster and better decisions,” he said.
Although there are restrictions regarding the use of drones in the UAE, Dr Frew said that he appreciated safety aspects needed to be considered, “but we know how to do it”.
“There are a lot of positive applications of drones like rain enhancement, where I do think that a flexible regulatory framework would be helpful,” he said.
Although it may take years for research programmes to deliver results in terms of increased rainfall, by funding such ideas the Rain Enhancement Programme is attempting to provide a fertile ground for scientists working in this field, in the hope that some of the ideas help them to yield more from the country’s own soil.