Hot deserts are mainly found in the tropics in a belt approximately 20°-30°N and 20°-30°S.
A number are on the western side of continents (e.g. South America and Africa). The largest expanse is across Northern Africa, into the Middle East and Asia
Climate
A desert is an area that receives less than 250mm of rainfall per year.
Day to night temperatures can fluctuate dramatically from 50°C in the day to below 0°C at night due to the lack of cloud cover.
Strong winds in the desert dry out plants.
Desert Soil
Desert soils are sandy and rocky and unable to hold much water
There is no organic content in desert soils
If water is near the surface, it evaporates, leaving salt in the soil.