Satellites captured images of lakes scattered across the Sahara desert after a cyclone dumped a year’s worth of rain on northern Africa in just a few days.
Lakes appeared in the Sahara after a storm brought floods to northern Africa, flooding swaths of land in the Earth’s largest hot desert, according to satellite images. The extratropical cyclone swept through parts of Morocco, Algeria, Tunisia and Libya on September 7 and 8, dumping up to 20 cm of rain in the affected areas, equivalent to a whole year’s worth of rain in just a few days. , according to NASA’s Earth Observatory.
The floods filled many temporary lakes in the Sahara, including Sebkha el Melah in Algeria and several others around Erg Chebbi, a vast star-shaped sand dune area in Morocco. NASA’s Moderate Resolution Imaging Spectrometer (MODIS) on the Terra satellite also imaged a number of temporary lakes that appear across Morocco and Algeria.
The lakes of Erg Chebbi filled with water after rivers from the neighboring Atlas Mountains overflowed near Merzouga, a town not far from the Algerian border that serves as an entrance to the star-shaped sand dunes. Photo taken on October 1 by one of the Copernicus Sentinel-2 satellites shows many new lakes scattered around the edge of Erg Chebbi.
NASA’s Landsat 9 satellite photographed the watery Sebkha el Melah lake in Algeria. Photos taken between August 12 and September 29 shared by the Earth Observatory show changes in the landscape, with a blue lake in the desert. The lake covers 191 square kilometers and is about 2.2 meters deep, according to calculations by Moshe Armon, a lecturer at the Hebrew University of Jerusalem. Armon uses satellite images to determine water coverage combined with 3D maps of the lake.
Since 2000, there have been two times when the water level in Sebkha el Melah has been higher than today. In 2008, the lake filled with water after an extratropical cyclone caused particularly heavy rain. Four years later, the lake completely dried up again. The water filling Lake Sebkha el Melah will likely last for some time. “Without any more rain, the current 2.2 meter deep water level will take about a year to completely evaporate,” Armon said.
Understanding how September’s cyclone rain event impacted the Sahara Desert will help researchers better understand what the desert looked like thousands of years ago and how the landscape would have changed. in the future due to climate change. Researchers predict many places in the Sahara will experience more rain.