Salts have also proven a great resource for the Chilean economy although today its lithium resources have also taken prominence on the world stage as battery development increases for better power storage and production in the new generation of electric cars No other desert has as much abundant salt as this desert.
It is estimated that during the First World War alone, some 3 million metric tons were mined. Like the US deserts, copper is present in Chile. Australia's deserts are a source of lead and zinc, uranium, gold and silver. As far as non-metal resources are concerned, deserts are also home to clay, beryllium, pumice where there was past volcanic activity , nitrates and lithium.
It is also no great surprise that some of our most abundant oil deposits are found in desert regions, particularly the Middle East, central and South America, in the driest places on Earth.
These were once marine environments, but the lakes and seas dried up, allowing for the chemical processes that turn organic material into crude oil to create enormous deposits. Oil is not unique to dry environments though and the most important process is the presence of organic material and the right chemical conditions. There is some debate whether the Bedouin tribes of the Middle East are true nomads in the traditional sense. They certainly perceive their lifestyle in this way although technically they live a semi-nomadic life.
In summer, they settle on lands bordering deserts where agriculture is possible and food crops for livestock is abundant. They tend to move around a lot more in the fall and winter time during the rainy season There are different groups of Bedouin tribe who name and classify themselves based on the types of livestock and animals that they rear. For example, there are camel Bedouins which comprise the largest tribes and are distributed over the widest areas of the Middle East, incorporating most of the Levant Jordan, Syria, Iraq the Arabian Peninsula and North Africa including Egypt, Libya and Sudan.
Much of their lifestyle is unchanged since the Bedouins first roamed the lands although not completely. They have adapted to many aspects of modern life including motor vehicles to move around where possible. Just as the technologies of Bedouin tribes have changed, so have the concept of a home which can be a tent, a stone building or even the desert land They are ethnically Arab, and most are now Muslim. Relationships between other ethnic Arabs and Bedouins has always been mixed.
The Bedouin are not the only nomadic or semi-nomadic life. The Marsh Arabs so brutally oppressed by Saddam Hussein in the early s were semi-nomadic, as are some elements of the Kurdish peoples of southeastern Turkey.
Some aspects of Mongolian life in the Gobi Desert, and the Sami people of northern Scandinavia and the arctic islands such as Svalbard continue in their semi-nomadic traditions. Like their counterparts to the south, they too are increasingly moving to permanent settlement. Deserts are vital in many ways ecologically. Water is vital to life and although they lack this necessary resource, their unique ecosystems provide survival and resources for the plant and animal species that live there Deserts carry out vital planetary environmental functions too.
Most of these species have adapted to the uniquely harsh environments of both hot and cold deserts and everything in between. Often, these species do not exist in other types of environment.
For that reason alone, it's necessary to conserve desert spaces and to avoid encroaching on them unnecessarily or altering them for other purposes. They are home to various livestock such as camels, goats, and antelope that provide food and livelihood for people. Desert shrubs and trees that produce fruit such as dates, figs, and olives 32 , are important food crops globally. Many are not aware that deserts are a net carbon sink, providing some relief from the increase in greenhouse gases.
This will be problematic while carbon emissions continue to increase, and world governments will need to do something about it in the future. The discovery was made when researching bacteria in the desert. Research suggests that bacteria located in massive aquifers beneath the sand and in the sands itself, are capturing carbon from the air.
Finally, deserts, due to their location, are important sources of generating renewable energy. It is no coincidence that the world's solar arrays are located in the hottest places on the planet. Smaller solar panels convert light into energy, but the large arrays in the deserts work differently. They harness the heat and use mirrors to reflect and divert into the array, to generate much more energy per square foot. Deserts are also useful sources of wind power.
There are always desert winds, but at certain times of the year wind is much higher which can also generate energy Deserts attract millions of visitors every year. From the deserts of the Middle East and North Africa where visitors may see the Great Pyramids of Giza in Egypt, to Jordan's city of Petra, Carthage and others, they are great places to see well-preserved archaeological ruins of the past.
Here in the USA, there are plenty of other examples of ancient cultures in the desert. In South America there are many sites and artefacts recovered from the Atacama. In short, people have settled deserts for hundreds of thousands of years and the dry nature makes such remains attractive to visitors Not that culture and history is the limit of desert leisure and tourism.
Some visit to see natural wonders such as Grand Canyon in Arizona, the great salt plains of the Atacama Desert or take a 4x4 vehicle or a hot air balloon ride across the sand dunes of the Arabian deserts. The semi-arid Monegros Desert in northeastern Spain plays host to an annual music festival called Monegros Desert Festival while the cold and arid landscapes of Greenland and Iceland draw visitors from all over the globe. The wide-open spaces of deserts can host great numbers of people without putting too much of a strain on local infrastructure.
Despite the strain that tourism can put on these delicate ecosystems, they are providing much-needed money and jobs to areas. Ecotourism is helping developing nations especially find ways of preserving those landscapes 36 when historically, deserts have been neglected both in the conservation debate, and the funding and planning. Geological data suggests that at 43 million years, the Namib Desert in southwestern Africa is the world's oldest desert, but by no means its largest that would be the Sahara.
Most remarkably, nothing has changed there for some 2 million years, surviving multiple Ice Ages It consists almost entirely of sand dunes and gravel plains and is one of the most inhospitable places in the world and it runs right up to the South Atlantic coast. It takes up almost half the surface area of Namibia. It's long history and dry environment makes it a perfect searching ground for archaeologists and anthropologists; it's home to some of the oldest cave art in the world, preserved almost perfectly due to the desiccated conditions.
Twyfelfontein is overshadowed by Brandberg for cave art, but the richness and diversity attract tourists and researchers alike It's hardly surprising that people settled here; Twyfelfontein contains one of the deserts few natural springs. The Namib Desert contains several national parks and reserves which home several species of zebra, jackals, and hyena. These warm-blooded mammals are in a precarious position due to the heat and dryness of the environment.
Yet not all the Namib is desert. While the north is dry and sandy, the south is more like a semi-arid region with succulents, and the central region is full of gravel and gypsum plains. The world's last continent is subject to international treaties that no single country can claim it.
Yet most developed nations have scientific settlements on the cold, dry and mostly inhospitable land What little life there is clings to the boundaries of where the land meets the sea and a few rocky outcrops. This includes penguins, albatrosses, seals, some species of gull and tern, and many types of insect. The interior is a different matter entirely. Covered in year-round snow and ice which is, in places, nearly 2km thick 1.
There is little precipitation and the snow and ice present has built up over hundreds of thousands of years. Rather than four seasons, it has just two: summer where it is always sunny where the sun never sets, and winter where it is always dark and the sun never rises. It's at the pole, so experiences the most extreme conditions of the planet. This especially means the temperatures. In , the Russian Vostok Station recorded the coldest ever temperature on planet Earth at In , satellite data appeared to suggest a lower temperature than this was recorded but it was never confirmed or backed up by other data There are steppe and mountains to the north, more desert to the west, plateau and plain to the south.
The plateau and plains to the south draw off moisture from that direction. The Indian Ocean is a hotbed of rainwater during monsoon season but the Gobi sees none of it.
An international team of scientists point out in a study the neglect suffered by the Sahara in conserving its biodiversity. As a result some emblematic species have disappeared such as the scimitar-horned oryx and others are on the verge of extinction the addax, the cheetah and the dama gazelle. The addax Addax nasomaculatus is a species of African antelope.
Biodiversity hotspots are those areas where generally, the number of species and endemism threatened per surface unit is greater and therefore, they are priority areas for conservation.
These hotspots relate to wetlands and forests where clearly there is a higher number of organisms , but also includes some desert areas like the Horn of Africa areas of Ethiopia and Somalia. The Sahara is a hot desert with special characteristics. Its size makes it the largest in the world with more than 11 million km 2 including the Sahel and it covers a greater surface than the Australian continent.
It has a vast topographical diversity from altitudes below sea level to mountains of 3, m and a varied climate. Its southern border with the Sahel is also a transition between two biogeographical regions the paleartic and the afrotropical and it extends across more than ten developing countries with great political and social instability. The areas with special protection that are regulated by treaties or specific agreements are the Arctic and the Antarctic. India bets its energy future on solar—in ways both small and big.
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Today, the Sahara is the largest hot desert in the world. These ridges inhibit the flow of moist air inland. The stark difference between 10, years ago and now largely exists due to changing orbital conditions of the earth — the wobble of the earth on its axis and within its orbit relative to the sun.
But this period ended erratically. In some areas of northern Africa, the transition from wet to dry conditions occurred slowly ; in others it seems to have happened abruptly. This pattern does not conform to expectations of changing orbital conditions, since such changes are slow and linear. But what caused the initial devegetation? But my recent paper presents evidence that areas where the Sahara dried out quickly happen to be the same areas where domesticated animals first appeared. At this time, where there is evidence to show it, we can see that the vegetation changes from grasslands into scrublands.
Scrub vegetation dominates the modern Saharan and Mediterranean ecosystems today and has significantly more albedo effects than grasslands. If my hypothesis is correct, the initial agents of change were humans, who initiated a process that cascaded across the landscape until the region crossed an ecological threshold. This worked in tandem with orbital changes, which pushed ecosystems to the brink.
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