The Harmattan is a season in West Africa that occurs between the end of November and the middle of March.
It is characterized by the dry and dusty northeasterly trade wind, of the same name, which blows from the Sahara over West Africa into the Gulf of Guinea.
On its passage over the Sahara, the Harmattan picks fine dust and sand particles (between 0.5 and 10 microns).
This season differs from winter because it is characterized by cold, dry,[4] dust-laden wind, and also wide fluctuations in the ambient temperatures of the day and night.
[12] A 2024 study found that dust carried by the Harmattan increases infant and child mortality, as well as has persistent adverse health impacts on surviving children.