"Unveiling the Enigmatic Greening of the Sahara Desert: New Research Sheds Light"
New research published in Nature Communications explains why and when the Sahara Desert experienced periodic green phases. Climate scientists used a climate model to simulate the North African Humid Periods and found that changes in Earth's orbital precession, which influenced the strength of the West African Monsoon system, were responsible for these humid events. The study also revealed that the humid periods did not occur during ice ages when large glacial ice sheets covered high latitudes, suppressing the expansion of the African monsoon system. Understanding these mechanisms provides insights into the dispersal of species, including early humans, out of Africa during different climatic periods.