The Sahara Desert was not always covered with sand. In the relatively recent past - 10 thousand years, and even earlier - about 30-50 thousand years ago, it was a giant green plain. Green Sahara, according to anthropologists today, helped our ancestors to leave Africa and spread throughout the Earth.
Over the past few million years, the Sahara has turned green several times and turned back into a desert, changing its appearance along with fluctuations in the Earth's climate and various geological processes.
Today, the climate is changing as quickly as it did when the Sahara was becoming a savannah or desert, prompting scientists to test what the desert and its southern outskirts, the so-called Sahel, will look like in the next hundred years. For this, scientists have created 30 different climatic models that took into account the change in the circulation of currents in the ocean and winds in the atmosphere over Africa, with a further increase in average annual temperatures.
About a third of the models showed that the Sahara will receive 40-300% more precipitation by 2100, and the increase will occur almost instantly, literally in 5 years or less, after the climatic system passes a certain temperature threshold. As a result, the territory of Chad, Niger, Mauritania, Mali and many other desert countries of Africa will be covered with savannas or jungles and will receive the same amount of rainfall as the countries of tropical Africa.
The reason for the changes will be global warming, which will affect the nature of the movement of monsoons off the coast of Africa and move them towards the Sahel in particular, and the entire Sahara in general. In addition, the rise in temperature will provoke faster evaporation of the Atlantic waters, which will intensify the monsoons and force them to carry more moisture towards the continent. This, in turn, will increase the difference in temperature between land and ocean and cause the winds to move even faster and carry more water to land.
Similar scenarios for the development of events in several models at once, as scientists note, indicate that the Sahara can really turn green already in the current century, if the rise in air and ocean temperatures does not stop. While these changes will be beneficial, they will affect the lives of over 100 million people living in the Sahel and the Sahara, therefore, as climatologists emphasize, the authorities of the countries of these regions must be prepared for such drastic changes.
Although this is still only a theory, time will show whether there will be a practical application of calculations.