The Sahara Desert is known as one of the driest places on Earth, receiving only about 3 inches of precipitation each year -- roughly one-tenth of what falls in Chicago.
However, new research from the University of Illinois Chicago (UIC) suggests that this could change dramatically within the next few decades. By the latter half of the 21st century, rising global temperatures may bring much more rain to the region. The study, published in npj Climate and Atmospheric Science, predicts that the Sahara could receive up to 75% more precipitation than its historical average. Similar increases are also projected for parts of southeastern and south-central Africa under extreme climate scenarios.
Rising Rainfall Could Reshape Africa
"Changing rainfall patterns will affect billions of people, both in and outside Africa," explained lead author Thierry Ndetatsin Taguela, a postdoctoral climate researcher in UIC's College of Liberal Arts and Sciences. "We have to start planning to face these changes, from flood management to drought-resistant crops."
Taguela emphasized that understanding how temperature increases influence rainfall is vital for developing adaptation strategies. His research used an ensemble of 40 climate models to simulate African summer rainfall during the latter half of the 21st century (2050-2099) and compared the results with data from the historical period (1965-2014). Two climate scenarios were examined: one assuming moderate greenhouse gas emissions and another assuming very high emissions.
In both scenarios, rainfall across most of Africa was projected to rise by the end of the century, although the changes vary by region. The Sahara Desert showed the largest increase at 75%, while southeastern Africa could see about 25% more rainfall and south-central Africa about 17% more. In contrast, the southwestern part of the continent is expected to become drier, with precipitation decreasing by around 5%.
Surprising Outlook for a Dry Region
"The Sahara is projected to almost double its historical precipitation levels, which is surprising for such a climatologically dry region," said Taguela. "But while most models agree on the overall trend of wetter conditions, there's still considerable uncertainty in how much rainfall they project. Improving these models is critical for building confidence in regional projections."
The increase in precipitation is largely linked to the warming atmosphere. Higher temperatures allow the air to hold more moisture, which contributes to heavier rainfall in some areas. Shifts in atmospheric circulation patterns also affect how and where rain falls, sometimes leading to both wetter and drier regions across the continent.
"Understanding the physical mechanisms driving precipitation is essential for developing adaptation strategies that can withstand both wetter and drier futures," Taguela said.
Taguela conducts his work as part of UIC's Climate Research Lab, led by Akintomide Afolayan Akinsanola. Their team continues to investigate how changing atmospheric conditions could reshape Africa's environment, agriculture, and long-term sustainability.