This is a statling statisctics given that many of us may never have come across deserts in our life time. Yet one fifth of the earth is such a huge chunk of earth. This therefore makes deserts even more intersting to study.
A desert can be defined as an area of land which is very dry because it receives very little amounts of rainfall and other forms of precipitation such as mist, snow and fog. The National Geographic estimates that any place receiving less than 10 inches of rain (approximately 25 centimeters) annually is considered to be a desert. These are very low amounts of rainfall and there is no guessing that life can be harsh in such a place. Yet as we will see later, deserts are rich in plant and animal life.
Another characteristic of deserts is that they experience very high levels of evaporation from the earth’s surface and transpiration from plants. This is because of the very high levels of temperatures found in these places, mostly due to direct sunlight hitting the ground. The reason for this is that due to low levels of precipitation, there is very little clouds to reflect back the sun rays, therefore much of the sun rays actually reach the earth’s surface. The temperature levels are so high that the National Geographic estimates that in North Africa’s Sahara desert, temperatures reaches 50 degrees Celsius during the day.
It is important to note that not all deserts of the world experiences very high temperatures. Indeed, we have cold deserts of the world. In these deserts, very low temperatures hinder most of the life forms and therefore the ground is largely bare and barren, just like in other deserts. Examples of cold deserts of the world are the Gobi desert in Asia and the desert found in the continent of Antarctica.
From the above description, it is possible to understand why deserts are vast areas with low vegetation cover and bare soil. Principally, conditions are so harsh that normal life is almost impossible. To thrive