Desert areas are generally hot during the day and cold at night. The wildlife and plants have managed to adapt over time to live and survive in these areas.
Deserts have extreme temperatures. During the day the temperature may reach 50°C, when at night it may fall to below 0°C. Deserts have less than 250 mm of rainfall per year. The rain can be unreliable. Most deserts are found between 20° and 35° north and south of the equator.
There are three factors which form desert areas:
the presence of high pressure, creating cloud-free conditions
cold ocean currents
mountain ranges to create rain shadows
The Sahara is the largest desert, covering 9 million km2.
Ways that plants and animals cope in deserts: Some plants are succulents and store the water in leaves, stems or roots. One example is the cactus. Other ways plants tolerate the dry conditions include:
long roots to tap into the water deep underground
short life cycles - a plant or seed could remain dormant until the rains come
Animal survival
Some may burrow to escape the heat.
Nocturnal animals sleep during the day, sheltering to help prevent dehydration.
Animals may hibernate during temperature highs or lows.
(BBC BITESIZE, 2014)
Overview
Temperature often remains above 30°C for long periods.
They tend to receive an average of less than 300mm of rain each year.
Desert soils are alkaline, and are very dry with little humus.
Plants have to cope with very little water in the hot desert. Species such as cacti have evolved to reduce water loss to a minimum.
Many plants have seeds that only germinate when the rains come.