<p class=ql-align-justify>One thing all deserts have in common is they are arid or dry. Most experts agree a desert is an area of land receiving no more than ten inches of precipitation a year. The amount of evaporation in a desert often greatly exceeds the annual rainfall. In all deserts there is little water available for plants and other organisms.</p><p>Deserts are found on every continent and cover about one-fifth of Earth's land area.&nbsp;</p>