Describe and explain the different sources of water in hot desert environments. 6 marks.

There are three sources of water in hot desert environments. Exogenous streams, which often have a source outside of the desert margin, offer a permanent supply of water to certain parts of the desert such as the Colorado River in the USA. The remaining two types offer intermittent supplies, known as ephemeral rivers which flow occasionally, often appearing after rainfall and flood events, such as the Marshall and Plenty Rivers in the Simpson desert, Australia. Finally, endoreic rivers are those which flow inland and frequently dry up due to high levels of evapotranspiration. Beyond rivers as sources of water, aquifers and artesian basins can be found in many desert areas, as well as morning dew caused by cold ocean currents, such as the morning fog in the Namib desert caused by the Benguela Current.