In Algeria’s Sahara Desert, the temporary lake Sebkha el Melah has emerged, providing scientists a rare chance to study historical climate trends in the region.
Created by a cyclone that brought heavy rains to northern Africa in September, this ephemeral lake transformed the dry desert landscape into an unusual aquatic habitat, key for exploring the Sahara’s long-term climatic shifts.
Historical Context and Satellite Observation
NASA’s Landsat 9 satellite, through its Operational Land Imager-2 (OLI-2), has been tracking the lake’s formation, now spanning about 74 square miles (191 square kilometers) with a depth of 7.2 feet (2.2 meters).
The appearance of Sebkha el Melah offers a glimpse of the Sahara’s past landscape, particularly the African Humid Period, which occurred 11,000 to 5,000 years ago when the desert was more fertile due to shifts in Earth’s orbit that increased regional rainfall.
Evidence left by ancient humans, such as rock art with animals and hunting scenes, points to the Sahara’s greener past, though details on rainfall patterns and climate remain under debate.
Research Perspectives on Past Climate
There’s ongoing discussion among researchers about the exact conditions during the African Humid Period. While some geologists argue the climate may not have been consistently wet enough to sustain many lakes, others like Moshe Armon from the Hebrew University of Jerusalem suggest that extreme rainfall events, such as the recent one in the northwestern Sahara, may have been common enough to keep lakes partially filled over time.
The recent persistence of Sebkha el Melah aligns with similar past events, such as in 2008, when water lasted in the lakebed for several years, indicating the current lake may remain for months or longer.
Implications for Future Climate and Research
Sebkha el Melah’s formation underscores how extreme weather events shape desert landscapes and the value of satellite technology in studying water systems. Missions like NASA and France’s Surface Water and Ocean Topography (SWOT) play a crucial role in measuring water volume and movement, improving understanding of global water resources.
As climate shifts intensify, studying transient lakes like Sebkha el Melah becomes even more important, offering insights into past climates while informing projections of future landscape changes. Research on these lakes and their historical contexts enriches our understanding of Earth’s evolving climate and its impact on ecosystems worldwide.
