biome receiving less than 250mm precipitation per year
extreme diurnal temperature variation: scorching days, freezing nights
covers ~33% of Earth's land surface including hot, cold, and coastal types
hot deserts: Sahara, Arabian, Sonoran; cold deserts: Gobi, Antarctic interior, Patagonian
organisms exhibit specialized adaptations: succulence, nocturnality, deep root systems, dormancy
soils are mineral-rich with low organic content, often with hardpan or salt crusts
aeolian processes (wind erosion and deposition) shape dunes, mesas, and desert pavement
sparse vegetation limits carbon cycle flux but desert dust fertilizes distant oceans
oases form where groundwater intersects the surface, sustaining isolated ecology
expanding due to desertification driven by climate change and land degradation
solar energy potential is highest in desert climate zones