In most deserts, the river beds end in closed basin or temporary lakes, don't follow them if you want to reach the sea.
Desert maps are relative, not always exact because of the sand shifting the landscape all the time.
In deserts, mirages can come up in summer when facing the sun, it is very difficult to affirm under what conditions and form
they appear.
One fifth of the earth's land surface is desert.
There are different types of deserts. Their soil can be made of salt as well as sand.
Some deserts are completely sterile where no plants nor animals can live, others can feed sheep and camels with a bit of grass and thorn bushes.
Deserts are very hot in the day but very cold at night. There are rarely any clouds to give protection from the sun or to retain heat at night so that great extremes of temperature occur.
There are about 50 deserts in the world, which represent 1/5 of the Earths surface.
Only small parts of the world's deserts are sand. (About 1/10 of the Sahara). The greater part is flat gravel cut by
dried up water courses wadis.
Most deserts lands were once fertile and some of the creatures that lived there then adapted to the new conditions.
At night in a desert, condensation of any moisture in the air can make some water available.
In a desert search for water, try digging at the lowest point of the outside bend of a dry stream bed or at the lowest point between dunes. Do not dig in the heat of the day, the exertion will cause unnecessary fluid loss.
Cactus plants and their roots can prove to be a valuable source of water in the desert. These plants are also a good place to collect overnight condensation.
Sweating is a cooling mechanism not a way of loosing moisture. If more fluid is drunk than needed it will be excreted and used to no purpose.
Without water you will last about 2 1/2 days at 48°C (120°F) if you spend the whole time resting in the shade, though you could last as long as 12 days if the temperature stays below 21°C (70°F).
