The components of The Sahara Desert have changed greatly over time .
Originally, before and during the last ice age , The Sahara was larger and just as dry as it is now. By the end of the ice age , the area of The Sahara had shrunk and become wetter but by 2500 BC , the monsoons ( caused by changes in pressure and melting of ice sheets from the ice age) retreated.
The Sahara Desert returned to its dry inhospitable climate, and it remains that way today.