You will be surprised to learn how deserts actually came to be!

You will be surprised to learn how deserts, which you thought were formed by the accumulation of sand, are actually formed! The Sahara Desert in North Africa reaches temperatures of up to 50°C, but these regions are not always formed by the heat.

The sun's rays are reflected perpendicular to the Equator, which means that solar energy is concentrated there. However, warm air from water and land masses rises, and this air has a greater capacity to hold moisture than cold air, which has no moisture. There are also a lot of oceans around the Equator and the air carries not only heat but also water vapor. The warm, humid air in those regions starts to cool as it rises, and so precipitation occurs due to condensation.

The air then leaves most of its moisture at the Equator and moves around the Equator towards the Tropics of Cancer and Capricorn. By the time the air reaches these latitudes, it has lost most of its moisture and becomes quite dry. This dryness and lack of rainfall, combined with complex air circulation patterns, leads to deserts. This air circulation is also known as Hadley cells.

Besides Hadley cells, continentality is also a major cause of desert formation. The concept of continentality refers to the distance of the land from the oceans and their climatic influence. Related to this, when water evaporates from water bodies, it has a precipitation effect on land. Regions close to water bodies also receive most of this moisture. In addition, as air moves inland, it loses much of its moisture. This causes air currents that travel long distances to lose moisture and dry out, leading to the formation of deserts in the interior of the region. For example, the Gobi and Takla-Makan Deserts are desert regions formed due to continentality.

In fact, deserts can be formed by warming or cooling air. As we mentioned earlier, cold air carries less moisture than warm air. Air at 30°C carries 30.4 grams of water per cubic meter.

Again, assuming that the air holds 100% relative humidity, when the air drops from 30°C to 10°C, the existing moisture turns into 9.4 grams of water per cubic meter. In this case, a drop in humidity to 31% is sufficient to create a desert.