The 11 types of desert, and their characteristics
The 11 types of desert, and their characteristics : One third of the earth’s surface is made up of deserts, but none of them is the same. There are many types of deserts and, unlike what one might think, not all of them are limited to being a place where the sun rages and the heat drowns us.
There are tropical, dry and sandy deserts like the Sahara, but there are also sparse landscapes full of ice, frost and darkness like Greenland. Be they cold or warm, all of them are characterized by having little rainfall, which conditions the life forms that inhabit them.
Then we will know the different types of desert that there are, their climatological characteristics and some species that can be found in them.
The types of desert, classified and explained
When we see the word “desert” the first image that comes to mind for the vast majority is the Sahara: a vast place of dunatic landscape, full of sand and without vegetation. This African desert has become the prototype of what we know as a desert and, in fact, its name comes from the Arabic “aṣ-Ṣaḥrāʾ al-Kubrā” which literally means “the Great Desert”.
This is why any landscape that resembles the Sahara in one way or another is easily identified as a desert: Atacama, Australia, much of the United States … However, It is not the heat or having a landscape made of sand that makes a territory considered a desert, but rather how much rain falls on it. For this reason it should not surprise us that places like Greenland, that great island-continent made practically of ice, qualify as desert, in fact, one of the largest.
Before talking more about the types of desert it is necessary to understand exactly what they are. Deserts are one of the 15 biomes that exist on earth, that is, they are sets of ecosystems and these are characterized by having less than 225 millimeters of annual rainfall. As they are places where there is little rain, these territories are dry areas, which completely conditions the development of life, although this does not mean that no living organism inhabits.
There is little diversity of organisms and, in fact, there is little organic matter, a shortage of nutrients and, in general, very few plant and animal species. The few species that live there are very adapted to life in the desert, be it cold or hot, and on many occasions we find Extremophilic species. These can withstand very difficult living conditions such as the scarcity of water and extreme temperatures, with very high values, above 40ºC, or very low, below -40ºC.
Having understood what deserts are, it is time to get down to business and discover what types of desert exist. As we said, there are not only warm ones, as the Sahara would be, but there are also cold ones and they can present other distinctive peculiarities.
The 11 types of desert, and their characteristics 1. Tropical deserts
We start with the prototypical deserts. Tropical deserts are those ecosystems that are located near the terrestrial equator. Most of the known deserts and, being close to the equatorial strip, receive a large amount of solar radiation, which makes them very hot places.
These deserts are formed because of the winds present at these heights, the trade winds, preventing the formation of clouds and preventing rain. Combined with the extreme heat, these places are very dry and can well exceed 55ºC, depending on the time of year.
The Sahara desert is the typical tropical desert, and so are the Syrian-Arabian desert, which is practically the eastern continuation of the great North African desert, the Thar desert and the Kalahari desert. Part of the Australian desert would also fall into this category.
2. Polar deserts
The polar deserts are places where there is little rain, have few plant and animal species and are large flat plains, as is the case with tropical deserts. They are alike in many ways except one: its highest temperature per year does not exceed 10ºC. In fact, the average temperature in these places is -20ºC and they can be below -40ºC. It is very cold.
As the temperature is lower than the freezing point of the water, in these places we do not find sand dunes as in the Sahara, but huge and extensive layers of ice where it is difficult for any plants to grow. Examples of this are Greenland and Antarctica, with ice sheets that are 2 km thick.
The 11 types of desert, and their characteristics 3. Cold or mountain deserts
Cold or mountain deserts are those that, as their name suggests, They form at high altitudes, where ecosystems are located in places with very low temperatures, low pressure, little oxygen, and little rainfall..
This causes that in some areas of the mountains plateaus are formed where life is composed mainly of lichens. Some deserts of this type are found in Tibet, Patagonia, the Andes and some areas on the periphery of the Arctic.
4. Monsoon deserts
Although the word “Monsoon” makes us think of torrential rains, the truth is that monsoon deserts are like the others, dry and arid, but they are related to this weather event. These deserts do not form in the monsoon areas, but in the coastal areas of the Indian Ocean as a consequence of the trade winds carrying the precipitation to the interior areas and discharging there, far away, leaving the coast without any rain. The desert of Rajasthan is an example of this.
The 11 types of desert, and their characteristics 5. Coastal deserts
Coastal deserts are found on the western edges of the continents found in the Tropics of Cancer and Capricorn. Despite being close to the coast, they are impacted by cold ocean currents, which, together with the presence of the trade winds, maintains a situation of atmospheric stability that prevents precipitation from occurring, which translates into much aridity.
In these places it is very rare that it rains. In fact, on average it rains only once every 5 or 20 years depending on the location. However, fogs may appear that mitigate the lack of water a little and, in the places where it is more present, the ground is totally soaked, causing some meadows to prosper and the occasional tree, cactus and lichens to grow. These fogs are equivalent to about 600 mm of “normal” rain.
Some examples of these deserts are in the coastal part of Western Sahara, Namibia, Australia and the desert between Chile and Peru.
6. Continental deserts of middle latitudes
These deserts occupy vast expanses ranging from central Asia, in Mongolia and China to Turkmenistan and the shores of the Caspian Sea. Examples of them are the Gobi, the Taklamakan and the Karakum, in addition to the deserts of Iran, Iraq and Syria. We can also consider deserts of this type those of the western United States and those of Australia.
The continental deserts of Asian mid-latitudes have summer rains and a very strong thermal amplitude. In summer they are warm places, with temperatures close to 25ºC, but winters are dry and harsh, dominated by the Siberian anticyclone and with temperatures below zero for several months in a row.
7. Subtropical deserts
Subtropical deserts are near the equator, but are not impacted by trade winds. They are areas with high atmospheric pressure that are far from the oceans and seas, so they receive little rainfall. In part, the Sonoran desert could be considered as a subtropical desert, although it can also be said that the North American deserts have some peculiar features that we will see below.
The 11 types of desert, and their characteristics 8. Deserts of North America
North America is a very large region, enough to have its own group of deserts. Although its deserts have characteristics typical of those of the tropics and mid-latitudes, those that stretch between the southwestern United States and central Mexico have very interesting characteristics that make them different from the rest.
These include hyper-arid areas with almost no vegetation but, altogether, removing the salt flats and dune fields, its biomass is much higher compared to the rest of deserts. They are places where complex and highly diversified ecosystems are located.
The most characteristic is that of Sonora, which has a very extensive vegetation, especially in the form of cacti of all kinds, heights and colors. One of its most distinctive cacti is the saguaro (Carnegiea gigantea), which can be 15 meters tall and can live up to 200 years. The flowers of this plant open at night so as not to be exposed to excessive heat and its main structure reserves large amounts of water.
9. Barrier deserts
Barrier deserts form in regions that are surrounded by large, high mountain ranges. Mountains act as barriers, preventing the entry of wind and rain-laden clouds, making them dry places not because of the heat or extreme radiation of the sun, but because they are deprived of rain. One such example is the Judean desert in Israel.
The 11 types of desert, and their characteristics 10. Australian deserts
The case of the deserts of Australia also deserves special attention, since there are no extreme deserts on that continent and its arid areas, from a climatic point of view, are rather limited. In fact, the territory receives rainfall between 150 and 400 mm per year, which means that in many desert places the rule that they must be places with little rain is not followed.
However, these rains are extremely irregular and can provide a lot, in a ratio of 1 to 10. This means that a season can grow a lot of vegetation in a specific place because it has started to rain frequently, but at a given moment it no longer There is rainfall again, causing the entire fertile ground to dry out completely. Ecosystems change a lot and the only vegetation that is assured of survival is extreme.
The Australian outback is very dry, so much so that almost every year there is a huge fire, fires that have been produced for thousands of years by the natives and, since the modern Australian has settled, the new settlers. These fires kill the weakest plants to the fire, but it favors the growth of pyrophytic and xerophytic plants that resist it very well. The most characteristic vegetation are the mulga (Acacia aneura) and some eucalyptus.
11. Alien deserts
Alien deserts? What are they painting here? Taking into account the main characteristics of deserts, dry places, without rainfall, with extreme temperatures and little life, the landscapes of other worlds fall into this group. Any planet that has winds and has a solid surface has deserts, with Mars being the closest to our world.
The extraterrestrial deserts strictly comply with the characteristic of not having life. Well, at least as far as we know, there is no life on Mars, and this can be used for future research on the red planet since this world would serve to simulate how life would develop on other planets that, until now, have not been “Invaded” by any organism.
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