Desert
Low rainfall, generally less than 30cm per year, characterizes a desert
Many deserts are very hot (at least during the day), but some, such as the Great Basin and the Gobi Desert, are cold most of the year.
The dry environment often causes a dramatic difference in temperature between day and night
Grasses are usually found when water is available (they are dormant underground, or as seeds, when there is no water).
Succulents, such as cacti and euphorbs, and shrubs with specialized water-saving adaptations, are present.
Trees are uncommon or totally absent.