Having become an area of geopolitical uncertainty, the “Sahel” now refers to a land mass that defies classical geographic description. The bioclimatic zone model has long dominated the delineation of the Sahara and the Sahel. Average significant isohyetal lines were underscored according to their relationship to agricultural and pastoral activities. Accordingly, the 200 mm annual line is considered the cut-off for aridity, below which, with few exceptions, farming and livestock breeding are no longer possible.
However, this zonal categorisation was established using a scale incongruent with the scope of societal activity. Despite the convenience of being “natural”, this model leads to misleading analyses. In this way, the climatic environment is often associated with a lifestyle. However, zonal societies defy definition (delineation). All societies have territorial division rationales that cross through limits construed as natural.
Since the mid-2000s, the region has changed shape. Counter-terrorism initiatives have unified the Sahara-Sahel geopolitical entity under the single word “Sahel”. As reported by the press, the contours of the unstable areas where travel is “strongly discouraged” by the French Department of Foreign Affairs are surprising.