The landscape of a desert is continually changing from one minute to the next, due to the slightest change in the weather conditions. Wind and water are two of the most important weathering agents that help to form deserts and create their distinctive features. Because of the existence of wind and water in deserts, the land is constantly being shaped and reshaped , causing sand and rocks to be moved around and deposited in various ways.
Water is a very important weathering agent in deserts.
Deserts receive very little rainfall per year, and usually when the rain does fall, it falls all at one time. The rains come down with a rush, and because the lands are so dry, the water is not easily absorbed. These floods carry with them sediments taken up from the floors of the valleys, called the wadis. These sediments contain sand, pebbles, rocks, and even boulders. This force of water washes away the top layer of soil and erodes the rocks, leaving behind a layer of hard dry land.