Could the UAE and rest of Gulf see more rain? New data shows close to 19% rise in rainfall over 20 years

Severe storms that swept through the UAE last year unleashed the heaviest rainfall ever recorded in the UAE. But is the amount of rain increasing in the region year on year?

New data has revealed an 18.8 per cent increase in rainfall across the six member countries of the GCC- Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the UAE - between 2000 and 2022. While experts say tracking rain is fraught with difficulty, they add it is important to "err on the side of caution" and prepare for a future with more extreme weather.

The new statistics, released by the GCC Statistical Centre in the Atlas of GCC Statistics for 2024, did not provide total rainfall figures over the 22-year period for individual countries.

The Atlas, now in its ninth edition, collates key region-wide statistics on employment, population, growth and demographics, as well as environmental changes.

“I don't think we can confidently say it is increasing,” Hylke Beck, assistant professor of earth science and engineering at King Abdullah University of Science and Technology in Saudi Arabia, told The National. He pointed out that measuring rainfall is difficult due to various factors including variability in annual rates to regional differences in the GCC.

“There is huge inter-annual variability and rainfall is influenced by a wide range of factors, such as short-term weather variability, longer-term internal climate variability and human climate change. Additionally, the data are inherently uncertain.”

Difficulty in collecting data on rain

Scientists say climate change made last April's UAE's storm more severe, with increasingly extreme and frequent weather events expected in the future. But how much rain is falling is harder to quantify.

Prof Beck said some models did indicate future increases in rain across the Arabian Peninsula, particularly in the south, because a warmer atmosphere can hold more moisture and generate rain, but that these are “highly uncertain”.

“Different models provide varying projections, and while the average of these models indicates increases, it may not necessarily reflect reality," Prof Beck explained.

He also pointed to a 2020 study that actually found a decrease in rainfall across Saudi Arabia from 1978 to 2019. The report, Prof Beck added, was based on different sources, which highlights another major problem: the difficulty in obtaining reliable data. Rain gauges only cover one spot and models struggle to simulate rain accurately, with satellites incorrectly detecting precipitation.

“A change of 19 per cent is not that surprising, particularly when analysing such a short 20-year period,” said Prof Beck, regarding the new GCC statistics. “It would be expected as part of normal climate variability.”

Wetter days ahead?

More countries across the arid GCC are deploying cloud-seeding planes to boost rainfall and bolster limited groundwater. But tracking how much rain falls from seeding – firing chemicals clouds to coax out more rain – is arguably just as hard to measure.

Jos Lelieveld, director of the Max Planck Institute for Chemistry and professor at the Cyprus Institute, said that because climate is measured as the average weather over 30 years, a 20-year increase of nearly 20 per cent "could be significant", but is "consistent with climate change projections".

Other studies published over the last few years have also pointed to an increase in wetter days. Scientists at the UAE’s National Centre of Meteorology have discovered that annual precipitation is expected to rise by up to 30 per cent over much of the country during this century.

A separate study published in Nature Scientific Reports last year stated that climate change is causing temperatures in the UAE to increase more during the night than during the day. Increased atmospheric moisture levels are partly responsible for the trend, with the study also highlighting more rain in the future.

Diana Francis, an assistant professor at Khalifa University in Abu Dhabi, and one of the scientists behind this study, told The National that the new statistics from the GCC were “in line with our findings of an increase in rainfall over the subtropics” as a result of increased warming at the equator due to global warming.

The subtropics are zones to the north and south of the tropics. “With global warming, subtropics are projected to receive more rain and become like today’s tropic regions,” she said.

Countries should still prepare

The wild and wet weather that hit western Saudi Arabia on Monday also shows just how suddenly people can be affected. Video footage showed rain drenching pilgrims in Makkah, cars navigating waterlogged roads and flight delays reported at King Abdulaziz International Airport in Jeddah.

If tracking the exact amount of rain remains challenging, what is most important is that countries make their region more resilient against extreme weather events such as torrential downpours by building flood channels and detention basins, and by investing in early warning systems. In the aftermath of Dubai’s floods, authorities announced plans for a Dh30bn rainwater drainage network to guard against flooding and avoid the financial losses that can come in their wake.

This is crucial in light of the GCC's rising population. The Atlas of GCC Statistics also showed the population of the six GCC countries reached 57.6 million in 2023, up from 56.6 million in 2022. The population of Dubai, for example, has swelled to an estimated 3.65 million as of the end of 2023.

Prof Lelieveld said preparing for heavy rains depends on local conditions. "Generally, improved forecasting, early warning and improved drainage systems are called for," he said.

Prof Beck said despite the uncertainty in tracking rainfall, preparation was still crucial. “While there is substantial uncertainty in historical and future precipitation trends, I believe we should err on the side of caution,” he said. “And significantly increase investments in climate resilience measures, especially considering the expected population growth which will put more people at risk.”