Hot and dry deserts, such as the Sonoran Desert of Arizona and northwestern Mexico, are warm year-round with an extreme range of diurnal (daily) temperatures because of low humidity. Brief but heavy storms may occur seasonally. Soil is hard and rocky. Burrowing mammals, insects and reptiles are the main fauna. The Great Sandy Desert of Australia and the Sahara of north Africa fall under this category.
Semi-AridSemi-arid deserts, such as the Great Basin of Nevada and western Utah, have long dry summers plus winter rainfall. Dew fall may exceed rainfall. Soil is sandy and rocky, and may include “caliche” (pans of calcium carbonate). Fauna is consistent with hot and dry deserts.
