Meteorologists debunk claim historic UAE floods caused by cloud-seeding
Videos and tweets circulating on social media claiming to link the historic rainfall and flooding experienced by the UAE recently to cloud seeding programmes conducted by the country.
On 16 April 2024, the UAE experienced 250 mm of rain, or equivalent to a year’s worth of rainfall in 12 hours, causing severe flooding. Five people were confirmed to have died from the floods. Rainfall surpassed levels since records began in 1949.
Social media users speculated that the country’s cloud seeding programme was to blame. Among the most widely viewed videos on the subject included a 22-second TikTok by user @dannyrayes who claimed that the historic rainfall had submerged the UAE in rainwater, garnering over a million interactions on the platform.
Faqcheck’s review of the circulating content found that the claims regarding cloud seeding in the UAE were false.
What is cloud seeding?
Cloud seeding is the practice of adding small particles into clouds, where their wind, moisture or dust conditions are not enough to cause rain.
This is practised in many countries, including the UAE, to encourage rainfall due to its arid climate. Aircraft and drones are used to fly through clouds, burning salt flares to stick rain droplets together to increase their weight.
The deputy-general of the UAE National Centre of Meteorology, Omar Al Yazeedi, speaking to the Independent explained that prior to the storm event no cloud-seeding operations were conducted.
“The essence of cloud seeding lies in targeting clouds at an earlier stage, prior to precipitation. Engaging in seeding activities during a severe thunderstorm scenario would prove futile”.
Meteorological experts agree with Al Yazeedi.
Commenting on the issue, meteorologist Professor Maarten Ambaum from the University of Reading further rejected the notion that cloud seeding was to blame: “No technology in existence can create or even severely modify this kind of rainfall event."
What caused the storm?
Professor Suzanne Gray, a Professor of Meteorology at the University of Reading attributes the historic rainfall to a mesoscale convective system or MCS. MCSs are large, organised clusters of thunderstorms, covering hundreds of kilometers. MCSs often bring heavy rain, strong winds and lighting.
These storm systems were seen previously in the Middle East back in 2016, with a reported rainfall of 240mm. Professor Gray added that this figure was similar to the rainfall for this event, and commonly occurred in March and April.
These MCSs appeared to have been modelled in advance by models such as the Global Flood Awareness System (GloFAS) run by the European Commission, Professor Gray said.
On 10th April, GloFAS had forecasted areas of the UAE to experience rainfall more than 150mm (blue), and 300mm (red), within a 10 day range.
This was also forecasted in other climate and weather models, according to a tweet by PhD candidate in atmospheric science, Tomer Burg (@burgwx).
Is this storm an effect of climate change?
Dr Matthew Ashfold, atmospheric scientist and Associate Professor at the University of Nottingham Malaysia, in an interview with Faqcheck, detailed that the impact of climate change on MCSs is a current area of study.
“Scientists continue to study whether climate change is altering various MCS properties; one recent review suggested 'heavy rainfall from MCSs is likely to increase' which is broadly consistent with the known ability of a warmer atmosphere to hold more water vapour," Ashfold said.
Echoing the sentiment, Dr Friederike Otto, Senior Lecturer in Climate Science at Grantham Institute of Climate Change and the Environment at Imperial College London, explained that with increasing atmospheric temperatures “rainfall is becoming much heavier” globally, as a warmer atmosphere carries an increased amount of moisture.
“It [increasing temperatures] encourages water that is already in the sky to condense faster and drop water in certain places. So first, you need moisture. Without it, there’d be no clouds.”
Do MCSs occur in Malaysia?
Dr Ashfold said much of the rainfall tropical countries such as Malaysia experience are associated with cloud systems that can be defined as MCS.
“The rainfall rates seen in the recent event in UAE, reported as exceeding 250 mm (or around 10 inches) in 24 hours, do occur in Malaysia.” Ashfold noted.
He pointed out that similar daily rainfall amounts were reported during widespread flooding in December 2021, bringing rainfall equal to the average for a month. “In this case the weather system was defined as a ‘tropical depression’, where a large grouping of clouds also develops specific wind patterns," he added.
Is cloud seeding practised in Malaysia?
“Cloud seeding has been reported as a government response to both drought and haze problems in Malaysia in recent years. The idea would be to promote rainfall from specific clouds to help to alleviate these problems," Dr Ashfold explained, citing recent cloud seeding operations earlier this year in Penang and Sabah, following water supply difficulties due to droughts.
He noted that despite cloud seeding being conducted in many countries including Malaysia, there is limited evidence for its effectiveness and the extent of its impact on rainfall due to difficulties in collecting data.
“Robust scientific experiments are hard because it is not possible to compare the seeded cloud with what would have happened in an alternative reality in which the seeding did not occur,” concluded Ashfold.
