This map, created by the cartographer Carl Churchill In 2019, it reconstructed, based on the current topography of the Sahara, the network of lakes and watercourses that covered the region between 7,000 and 3,000 BC, according to data provided by palaeoclimatic research at the time.
The map shows the African Humid Period, a phase during which changes in the Earth’s orbit intensified the African monsoon and transformed much of North Africa into a savannah with permanent lakes. The colours used by Churchill follow the standard conventions for physical maps, and he has marked in blue the basins that have since disappeared, ranging from the various lakes in Algeria, Mali and Niger, to the great Lake Mega Chad.
Most of these lakes no longer exist, but traces of them remain in the form of dry riverbeds. The rock art found in the modern-day Sahara, featuring depictions of hippos, elephants and giraffes, helps to support this hypothesis. Churchill describes this work as a speculative reconstruction supported by recent research, but it is by no means an exact representation, as there is no palaeoclimatic data available to determine precisely the extent of each lake at that time.
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