Tropical or subtropical desert: warm and arid (very dry) year-round. Temperatures average above freezing year-round. Annual rainfall totals not more than 50 cm (19") and usually totals less than 25 cm (10"). Vegetation may be mostly or entirely absent in some regions, but in many areas, grasses and herbaceous plants, deciduous or evergreen broadleaf trees, or a mix may grow in patches.
By Dave Bryant, copyright 2002