What is the reason for the existence of the Sahara Desert?

The Sahara owes its existence to 3 different causes: ... Otherwise a thornscrub savanna or semidesert, nowadays you find barren ground in many places. ... of "Wet Sahara" or "Green Sahara", during which the region was much more moist and supported a richer biota and human population than the present-day desert. read more

The Sahara owes its existence to 3 different causes: Subtropical high pressure forms around 30 degrees North and South around the globe, because it is there where the rising humid air from the equator sinks back to the surface, dissolving all the clouds. read more

The Sahara is not the only desert to have dramatic climate change. The Ghaggar River, in what is now India and Pakistan, was a major water source for Mohenjo-daro, an urban area of the ancient Indus Valley Civilization. read more

The desert covers large sections of Algeria, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Western Sahara, Sudan and Tunisia. This is the image many people have of the Sahara: a vast sea of sand dunes. read more