Janice R. Andrews
In a stunning shift, parts of the Sahara Desert, one of the driest regions on Earth, are turning green. This transformation is driven by an influx of heavy rainfall that has triggered the growth of vegetation in typically barren landscapes. Satellite images released by NASA have captured this rare event, showing patches of plant life sprouting across vast stretches of the desert in Morocco, Algeria, Tunisia, and Libya.
This unexpected greening of the Sahara was brought about by an extratropical cyclone that drenched northwestern Africa between September 7 and 8, 2024. The rainfall poured into regions that typically receive only a few inches of rain annually, resulting in the rapid growth of shrubs, grasses, and even trees in riverbeds and low-lying areas. Climate researchers, including Sylwia Trzaska from the Columbia Climate School, confirmed that this kind of plant growth is rare but not entirely unprecedented.
A Desert Reborn: How Rain Transforms the Sahara
The Sahara, often associated with its endless sand dunes and parched landscapes, was once much greener. Historical studies suggest that between 11,000 and 5,000 years ago, the region was covered with lush vegetation, and lakes dotted the land. As Peter de Menocal, president of the Woods Hole Oceanographic Institution, notes, “When you get these exceptional rainfall events, the dunes become incredibly verdant fields where plants thrive for a short period.”
This rapid response of plant life is due to the unique adaptation of the flora in this region. The desert plants have evolved to take advantage of rare rainfalls, growing quickly in a race against time to soak up water before it evaporates. The recent downpour, which brought over half a foot of rain in some areas, allowed for the sudden resurgence of greenery that had been dormant for months, if not years.
Impact of Rain on Desert Lakes and Flooding in Africa
Lakes in the region, typically dry, are also experiencing a remarkable transformation. For example, Sebkha el Melah, a salt flat in central Algeria, filled up after the storm—a phenomenon that has only occurred six times in the past two decades. Satellite analysis confirms that this is one of the most significant rain events to hit the region in years.
While the greening of the Sahara is an exciting development for climate scientists, it comes amid widespread concerns about the devastating impact of extreme weather in other parts of Africa. Over 1,000 people have died from floods in West and Central Africa, including Chad, Nigeria, Mali, and Niger, as torrential rains continue to affect the region. According to the World Food Programme, around 4 million people across 14 countries have been displaced or impacted by the floods.
The Role of Climate Change in This Unusual Rainfall
Experts attribute the unusual rainfall in the Sahara to several factors, including the northward shift of the Intertropical Convergence Zone (ITCZ)—the tropical rain belt that usually hovers around the equator. Typically, the ITCZ does not reach as far north as the Sahara, but record-high sea surface temperatures in the Atlantic Ocean and shifting weather patterns due to climate change have altered the rain belt’s path.
Climate scientist Dan Harnos from NOAA’s Climate Prediction Center explains that the storm track, displaced farther north than usual, pulled moisture from equatorial Africa into the northern Sahara. This shift, combined with the transition from El Niño to La Niña, contributed to the extreme rainfall that has turned parts of the desert green.
A Glimpse into the Past—and the Future?
This event raises fascinating questions about the Sahara’s ancient past and the potential long-term effects of climate change. Between 11,000 and 5,000 years ago, during what scientists call the “Green Sahara” period, this vast desert was home to lakes, rivers, and dense vegetation. Some researchers believe that the current rainfall could offer a brief glimpse into what the Sahara might have looked like thousands of years ago.
However, as Moshe Armon from the Institute of Earth Sciences at the Hebrew University of Jerusalem warns, this greening is likely to be temporary. As soon as the rains stop, the desert will quickly revert to its usual arid state. Still, the changes provide a fascinating example of how resilient desert ecosystems can be in the face of shifting weather patterns.
Could the Sahara Become Green Again?
While some might wonder if the Sahara could permanently transform into a more fertile region, experts believe that this event is a short-lived anomaly. According to a study published in Nature earlier this year, climate change could cause rain belts like the ITCZ to shift even farther north in the future. This could result in more rainfall reaching the Sahara in the coming decades. However, as global temperatures continue to rise, ocean temperatures elsewhere will also shift, causing the rain belt to move southward again, possibly even past the equator.
As Peter de Menocal explains, “Decades from now, we expect the rain belt to go back to its original position, and it could even shift into the other hemisphere.” This suggests that the greening of the Sahara, while striking, is unlikely to become a permanent feature of the desert.
Conclusion: A Rare but Temporary Transformation
For now, the sight of green patches in the Sahara is a rare but visually stunning reminder of the planet’s ever-changing climate. While the greening of the desert will likely fade as quickly as it appeared, this event serves as a powerful example of how even the most extreme environments on Earth are not immune to the effects of climate change.
As scientists continue to monitor the Sahara’s transformation, the ongoing heavy rains across Africa remain a reminder of the broader impacts of climate shifts. From the ancient lakes of the Sahara filling up to the devastating floods affecting millions, the recent rains are shaping the future of Africa in ways both remarkable and tragic.
