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Numerous studies including sedimentology, pollen analysis, petrology, and morphodynamic provide considerable knowledge concerning the climatic evolution of the Senegalo-Mauritanian Basin.

Three dry stages in a cooling context are widely accepted during the Upper Pleistocene. The first one, before 100 kyr corresponds to the Akcharian period. It is associated with a regressive phase and the formation of aeolian dunes in the northern regions of the basin. The two other arid stages occured between 100 and 40 kyr BP (Ogolian I). This phase also corresponds with a regressive period. Aeolian processes were more active. NE-SW dune complexes developed in the South of Mauritania and in the northern region of Senegal.

The Late Pleistocene (40 kyr-12 kyr) is marked by two climatic phases: an arid one and a pluvial. The humid phase occured between 40 and 30 kyr BP during the Inchirian transgression. Isotopic data point to high temperatures of marine waters and an important arrival of fresh water. The arid stage corresponds to the 'Ogolian desert' period (Ogolian II). This period is characterized by decreasing temperatures and dune formation. The dunes are orientated NNE-SSW in most parts of the basin, from Mauritania to the Salum estuary.

The Holocene starts with warmer conditions of the littoral waters during semi arid conditions. Later, the Holocene experienced pronounced climatic fluctuations of very wet periods (9 kyr, 6 kyr and 3.5 kyr BP) alternating with very arid periods (7 kyr, 4.5 kyr and 2 kyr BP).