As this wind-induced movement of sand grains takes place, the dune moves slowly across the surface of the ground. [103], The desert nomads were also traders. The deserts of North America have more than one hundred playas, many of them relics of Lake Bonneville which covered parts of Utah, Nevada and Idaho during the last ice age when the climate was colder and wetter. We'd just like to take a moment to apologise for the continued delays the site is currently experiencing. Desert farming is possible with the aid of irrigation, and the Imperial Valley in California provides an example of how previously barren land can be made productive by the import of water from an outside source. In Antarctica, for example, the annual precipitation is about 50 mm (2 in) on the central plateau and some ten times that amount on some major peninsulas. Dessert en 4 lettres. They travelled over large areas with their herds, moving to new pastures as seasonal and erratic rainfall encouraged new plant growth. Many, such as the Bushmen in the Kalahari, the Aborigines in Australia and various tribes of North American Indians, were originally hunter-gatherers. Saguaro grows slowly but may live for up to two hundred years. Some seed will not germinate until it has been blown about on the desert floor to scarify the seed coat. [5] Deserts generally receive less than 250 mm (10 in) of precipitation each year. The relief of the internal pressure that has built up in rocks that have been underground for aeons can cause them to shatter. These can experience flash floods, becoming raging torrents with surprising rapidity after a storm that may be many kilometers away. [102] An early historical account is that of Marco Polo (c. 1254–1324), who travelled through Central Asia to China, crossing a number of deserts in his twenty four year trek. We are no way affiliated with SCRABBLE®, Mattel, Spear, Hasbro, Zynga, or the Words with Friends games in any way. In fact, with a very few exceptions, their basal metabolic rate is determined by body size, irrespective of the climate in which they live. Many are nocturnal, and stay in the shade or underground during the heat of the day. Vegetation plays a major role in determining the composition of the soil. [53], Other non-sandy deserts consist of exposed outcrops of bedrock, dry soils or aridisols, and a variety of landforms affected by flowing water, such as alluvial fans, sinks or playas, temporary or permanent lakes, and oases. [112] It has been found that plant growth-promoting bacteria play a role in increasing the resistance of plants to stress conditions and these rhizobacterial suspensions could be inoculated into the soil in the vicinity of the plants. European interest in the Sahara Desert stems from its two aspects: the almost continual daytime sunshine and plenty of unused land. As the wind blows, saltation and creep take place on the windward side of the dune and individual grains of sand move uphill. This area of deposited clay, silt or sand is known as a playa. They took with them their tents made of cloth or skins draped over poles and their diet included milk, blood and sometimes meat. We're working closely with our server provider and will try to get things back to normal as soon as possible. [76] Many examples of convergent evolution have been identified in desert organisms, including between cacti and Euphorbia, kangaroo rats and jerboas, Phrynosoma and Moloch lizards. Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks, which consequently break in pieces. [66], Lakes may form in basins where there is sufficient precipitation or meltwater from glaciers above. In some places the wind has carved holes or arches, and in others, it has created mushroom-like pillars narrower at the base than the top. [47] A hamada is a type of desert landscape consisting of a high rocky plateau where the sand has been removed by aeolian processes. [110] Geological processes in a desert climate can concentrate minerals into valuable deposits. Bottomlands may be salt-covered flats. In many ways, birds are the ablest to do this of the higher animals. [37] Denser clouds of dust can be formed in stronger winds, moving across the land with a billowing leading edge. Others occur on the eastern side of the Rocky Mountains, the eastern side of the southern Andes and in southern Australia. [23] The Taklamakan Desert is an example, lying in the rain shadow of the Himalayas and receiving less than 38 mm (1.5 in) precipitation annually. The River Nile, the Colorado River and the Yellow River do this, losing much of their water through evaporation as they pass through the desert and raising groundwater levels nearby. [7][8], Deserts have been defined and classified in a number of ways, generally combining total precipitation, number of days on which this falls, temperature, and humidity, and sometimes additional factors. [120], The Arabs were probably the first organized force to conduct successful battles in the desert. Here are the possible solutions for deserts clue The Martian deserts principally consist of dunes in the form of half-moons in flat areas near the permanent polar ice caps in the north of the planet. Many desert reptiles are ambush predators and often bury themselves in the sand, waiting for prey to come within range. Other deserts are flat, stony plains where all the fine material has been blown away and the surface consists of a mosaic of smooth stones. They include the Tengger and Sonoran Deserts. [107], Similar damage is being done today to the semi-arid areas that rim deserts and about twelve million hectares of land are being turned to desert each year. They then reproduce rapidly while conditions are favorable before returning to dormancy. Birds have avoided the problem of losing heat through their feet by not attempting to maintain them at the same temperature as the rest of their bodies, a form of adaptive insulation. In the First World War, the Ottoman Turks were engaged with the British regular army in a campaign that spanned the Arabian peninsula. However, such factors as the temperature, humidity, rate of evaporation and evapotranspiration, and the moisture storage capacity of the ground have a marked effect on the degree of aridity and the plant and animal life that can be sustained. The semi-arid fringes of the desert have fragile soils which are at risk of erosion when exposed, as happened in the American Dust Bowl in the 1930s. Winter temperatures vary considerably between different deserts and are often related to the location of the desert on the continental landmass and the latitude. They are transported by creep, being rolled along the desert floor or performing short jumps. [77], Deserts present a very challenging environment for animals. Evaporation can concentrate minerals as a variety of evaporite deposits, including gypsum, sodium nitrate, sodium chloride and borates. Such electric fields, which range in size up to 80 kV/m, can produce sparks and cause interference with telecommunications equipment. [50] Dunes are sometimes solitary, but they are more often grouped together in dune fields. [109], Deserts contain substantial mineral resources, sometimes over their entire surface, giving them their characteristic colors. [20] They usually feature BSh (hot steppe) or BSk (temperate steppe) in the Köppen climate classification. For perennial plants, reproduction is more likely to be successful if the seed germinates in a shaded position, but not so close to the parent plant as to be in competition with it. [126], The desert is generally thought of as a barren and empty landscape. [24] [65] Seepages may occur in the walls of canyons and pools may survive in deep shade near the dried up watercourse below. Problems they need to solve include how to obtain enough water, how to avoid being eaten and how to reproduce. This site is for entertainment and informational purposes only. [104] Several million slaves may have been taken northwards across the Sahara between the 8th and 18th centuries. [136] Examination of the surface of rocks by laser beamed from the Mars Exploration Rover have shown a surface film that resembles the desert varnish found on Earth although it might just be surface dust. Below you will find the correct answer to Dry like deserts Crossword Clue, if you need more help finishing your crossword continue your navigation and try our search function . [11] Polar deserts cover much of the ice-free areas of the Arctic and Antarctic. Warfare in the desert offered great scope for tacticians to use the large open spaces without the distractions of casualties among civilian populations. [108] Desertification is caused by such factors as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation. As the desert dries out, the adult toads rebury themselves. Deserts are a big part of UAE's heritage and history. They developed skills in the manufacture and use of weapons, animal tracking, finding water, foraging for edible plants and using the things they found in their natural environment to supply their everyday needs. They share some characteristics of a true desert and are usually located at the edge of deserts and continental dry areas. [87] Jerboas, desert rats, kangaroo rats and other small rodents emerge from their burrows at night and so do the foxes, coyotes, jackals and snakes that prey on them. The repeated fluctuations put a strain on exposed rock and the flanks of mountains crack and shatter. Evaporation brings moisture to the surface by capillary action and calcium salts may be precipitated, binding particles together to form a desert conglomerate. For arid climate, see, Area of land where little precipitation occurs, International Center for Agricultural Research in the Dry Areas, "How mountains influence rainfall patterns", "CHAPTER 8: Introduction to the Hydrosphere (e) Cloud Formation Processes", "The formation of fine particles in sandy deserts and the nature of 'desert' loess", 10.1306/74d71a69-2b21-11d7-8648000102c1865d, "Physics, Mechanics and Processes of Dust and Sandstorms", "Retrieval of mass and sizes of particles in sandstorms using two MODIS IR bands: A case study of April 7, 2001 sandstorm in China", 10.1175/1520-0450(1969)008<0032:GCODD>2.0.CO;2, "The electrification of snowstorms and sandstorms", "Misconceptions surround desert terrain, vegetation", "Desert varnish: evidence for cyclic deposition of manganese", "Geology of Grand Canyon National Park, North Rim", "Even the Driest Place on Earth Has Water", "Two dry for life: the Atacama Desert and Mars", "Too dry for life: The Atacama Desert and Mars", "Colonel Qaddafi and the Great Man-made River", "Nature's green revolution: the remarkable evolutionary rise of C4 plants", "How Plants Cope with the Desert Climate", "Adaptation to cold in arctic and tropical mammals and birds in relation to body temperature, insulation, and basal metabolic rate", "Kidney mass and relative medullary thickness of rodents in relation to habitat, body size, and phylogeny", "A method for the calculation of metabolic water", "What secrets lie within the camel's hump? Many locations within this category have elevations exceeding 3,000 m (9,800 ft) and the thermal regime can be hemiboreal. [70] The stems and leaves of some plants lower the surface velocity of sand-carrying winds and protect the ground from erosion. Berbers with knowledge of the region were employed to guide the caravans between the various oases and wells. Advertising ensures that the site free to use. [112] A field trial in the Sonoran Desert which exposed the roots of different species of tree to rhizobacteria and the nitrogen fixing bacterium Azospirillum brasilense with the aim of restoring degraded lands was only partially successful. Thanks for visiting The Crossword Solver. Exemple: "P ris", "P.ris", "P,ris" ou "P*ris" Rechercher. The smooth flat surfaces of playas have been used for attempted vehicle speed records at Black Rock Desert and Bonneville Speedway and the United States Air Force uses Rogers Dry Lake in the Mojave Desert as runways for aircraft and the space shuttle. Which desert is spelled with four letters. [8] For example, Phoenix, Arizona, receives less than 250 mm (9.8 in) of precipitation per year, and is immediately recognized as being located in a desert because of its aridity-adapted plants. Moist warm air rises over the land, deposits its water content and circulates back to sea. Deserts can be classified by the amount of precipitation that falls, by the temperature that prevails, by the causes of desertification or by their geographical location. Solutions pour: déserts de sable - mots fléchés et mots croisés Sujet Solution Lettres Chance Options déserts de sable ERGS 4 trouvé Sujets similaires. [79] Oxidising a gram of carbohydrate produces 0.60 grams of water; a gram of protein produces 0.41 grams of water; and a gram of fat produces 1.07 grams of water,[80] making it possible for xerocoles to live with little or no access to drinking water. The Turks were defeated by the British, who had the backing of irregular Arab forces that were seeking to revolt against the Turks in the Hejaz, made famous in T.E. In hot deserts, the temperature during daytime can exceed 45 °C (113 °F) in summer and plunge below freezing point at night during winter. [4], A desert is a region of land that is very dry because it receives low amounts of precipitation (usually in the form of rain, but it may be snow, mist or fog), often has little coverage by plants, and in which streams dry up unless they are supplied by water from outside the area. Suspension is only possible for particles less than 0.1 mm (0.004 in) in diameter. When these are extensive, they are known as sand seas or ergs. [34], As the mountains are eroded, more and more sand is created. Opening stomata to allow in the carbon dioxide necessary for the process causes evapotranspiration, and conservation of water is a top priority for desert vegetation. Some cold deserts are far from the ocean and others are separated by mountain ranges from the sea, and in both cases, there is insufficient moisture in the air to cause much precipitation. Some are deciduous, shedding their leaves in the driest season, and others curl their leaves up to reduce transpiration. Which desert is spelled with four letters? [78], Water and carbon dioxide are metabolic end products of oxidation of fats, proteins, and carbohydrates. Other xerophytic plants have developed similar strategies by a process known as convergent evolution. [57], When rain falls in deserts, as it occasionally does, it is often with great violence. What does contingent mean in real estate? leave behind; "the students deserted the campus after the end of exam period". [123][124], In the Second World War, the Western Desert Campaign began in Italian Libya. Few make it to adulthood. [131] Another woman explorer was Freya Stark who travelled alone in the Middle East, visiting Turkey, Arabia, Yemen, Syria, Persia and Afghanistan, writing over twenty books on her experiences. Montane deserts are normally cold, or may be scorchingly hot by day and very cold by night as is true of the northeastern slopes of Mount Kilimanjaro. Eggs are laid and the tadpoles grow rapidly as they must reach metamorphosis before the water evaporates. [17], Based on precipitation alone, hyperarid deserts receive less than 25 mm (1 in) of rainfall a year; they have no annual seasonal cycle of precipitation and experience twelve-month periods with no rainfall at all. [38], During a sandstorm, the wind-blown sand particles become electrically charged. [39] A much smaller scale, short-lived phenomenon can occur in calm conditions when hot air near the ground rises quickly through a small pocket of cooler, low-pressure air above forming a whirling column of particles, a dust devil. When there are two directions from which winds regularly blow, a series of long, linear dunes known as seif dunes may form. The cold Humboldt Current and the anticyclone of the Pacific are essential to keep the dry climate of the Atacama. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. When they reach the crest, they cascade down the far side. Definition and occurrence. [21] Monsoon deserts are similar. Animals need to keep cool and find enough food and water to survive. Once fertility has been built up, further crop production preserves the soil from destruction by wind and other forms of erosion. In order to conserve energy, other desert birds run rather than fly. Some of these cookies will send your data to our advertising partners. [52] In time, bacteria that live on the surface of the stones accumulate a film of minerals and clay particles, forming a shiny brown coating known as desert varnish. Although rain seldom occurs in deserts, there are occasional downpours that can result in flash floods. Nombre de lettres. These areas are known as desert pavements, and little further erosion takes place. They can move to areas of greater food availability as the desert blooms after local rainfall and can fly to faraway waterholes. These belts are associated with the subtropical anticyclone and the large-scale descent of dry air moving from high-altitudes toward the poles. [37] In a really severe steady blow, 2 m (6 ft 7 in) is about as high as the sand stream can rise as the largest sand grains do not become airborne at all. Image Credit: Gulf News. [98], Humans have long made use of deserts as places to live,[99] and more recently have started to exploit them for minerals[100] and energy capture. When rain falls, the water is rapidly absorbed by the shallow roots and retained to allow them to survive until the next downpour, which may be months or years away. When they land, they strike other particles which may be jerked into the air in their turn, starting a chain reaction. What where michaels main struggles in the book heat by mike lupica? déserts de sable [47] Where sand does occur, it is usually in large quantities in the form of sand sheets or extensive areas of dunes. Heavy rain is the trigger for emergence and the first male to find a suitable pool calls to attract others. 5. Desert plants maximize water uptake by having shallow roots that spread widely, or by developing long taproots that reach down to deep rock strata for ground water. Définition ou synonyme. Polar deserts (also seen as "cold deserts") have similar features, except the main form of precipitation is snow rather than rain. They reduce visibility and can remain in the atmosphere for days on end, conveyed by the trade winds for distances of up to 6,000 km (3,700 mi). Nomads have moved their flocks and herds to wherever grazing is available, and oases have provided opportunities for a more settled way of life. This prospect has proved false as it disregarded the environmental damage caused elsewhere by the diversion of water for desert project irrigation. With annuals, such plants grow with great rapidity and may flower and set seed within weeks, aiming to complete their development before the last vestige of water dries up. [5] The potential evapotranspiration may be large but (in the absence of available water) the actual evapotranspiration may be close to zero. They occur in Namibia, Chile, southern California and Baja California. Désert d'Asie en 4 lettres. Other areas are arid by virtue of being a very long way from the nearest available sources of moisture. The whirling airborne grains act as a sand blasting mechanism which grinds away solid objects in its path as the kinetic energy of the wind is transferred to the ground. Tanks and armoured vehicles were able to travel large distances unimpeded and land mines were laid in large numbers. [133], The American poet Robert Frost expressed his bleak thoughts in his poem, Desert Places, which ends with the stanza "They cannot scare me with their empty spaces / Between stars – on stars where no human race is. They are often preceded by severe dust storms and occur when the wind velocity increases to a point where it can lift heavier particles. ", "Emperor Penguins: Uniquely Armed for Antarctica", "Invertebrates: A Vertebrate Looks at Arthropods", "Head of Kibbutz Movement: We will not be discriminated against by the government", "Trans-Saharan trade and the West African discovery of the Mediterranean", "First Measured Century: Interview:James Gregory", "Why is oil usually found in deserts and Arctic areas? [111] Why don't libraries smell like bookstores? Dasht-e Lut, also spelled Dasht-i-Lut and known as the Lut Desert, is a large salt desert in southeastern Kerman Iran and is the world's 25th largest desert [100], Oil and gas form on the bottom of shallow seas when micro-organisms decompose under anoxic conditions and later become covered with sediment. Even small fungi and microscopic plant organisms found on the soil surface (so-called cryptobiotic soil) can be a vital link in preventing erosion and providing support for other living organisms. [100] Other desert minerals are copper from Chile, Peru, and Iran, and iron and uranium in Australia. [101] Deserts play a significant role in human culture with an extensive literature. About one-third of the land surface of the world is arid or semi-arid. SCRABBLE® is a registered trademark. When did organ music become associated with baseball? Cold deserts often have high concentrations of salt in the soil. Deserts take up about one third of the Earth's land surface. This picks up particles of sand and dust and wafts them aloft in sand or dust storms. The grains end up as level sheets of sand or are piled high in billowing sand dunes. The sand streams along above the surface of the ground like a fluid, often rising to heights of about 30 cm (12 in). Some major oilfields such as Ghawar are found under the sands of Saudi Arabia. How to replace brakes on a 1997 Oldsmobile regency? Evapotranspiration is the combination of water loss through atmospheric evaporation and through the life processes of plants. Who is the longest reigning WWE Champion of all time? [15] In other words, about eight times more water could evaporate from the region than actually falls as rain. [16], Deserts are sometimes classified as "hot" or "cold", "semiarid" or "coastal". [128] Some accounts give vivid descriptions of desert conditions, though often accounts of journeys across deserts are interwoven with reflection, as is the case in Charles Montagu Doughty's major work, Travels in Arabia Deserta (1888). [100], Traditional desert farming systems have long been established in North Africa, irrigation being the key to success in an area where water stress is a limiting factor to growth. [33] There is a certain critical size (about 0.5 mm) below which further temperature-induced weathering of rocks does not occur and this provides a minimum size for sand grains. Clarke's Commentary on the Bible. They are also unpleasant for humans and can cause headaches and nausea. They used terracing techniques and grew gardens beside seeps, in moist areas at the foot of dunes, near streams providing flood irrigation and in areas irrigated by extensive specially built canals. The answer to this crossword puzzle is 4 letters long and begins with A. Search for clues, synonyms, words, anagrams or if you already have some letters enter the letters here using a question mark or full-stop in place of any you don't know (e.g. "cros...rd" or "he?p"). For these reasons, the front line moved back and forth through hundreds of kilometers as each side lost and regained momentum. The desert surface is evidence of this with dry stream channels known as arroyos or wadis meandering across its surface. [21], In some parts of the world, deserts are created by a rain shadow effect. This exposes coarser-grained material, mainly pebbles with some larger stones or cobbles,[36][47] leaving a desert pavement, an area of land overlaid by closely packed smooth stones forming a tessellated mosaic. [121], The Negev Desert, Israel, and the surrounding area, including the Arava Valley, receive plenty of sunshine and are generally not arable. The air is very cold and carries little moisture so little precipitation occurs and what does fall, usually snow, is carried along in the often strong wind and may form blizzards, drifts and dunes similar to those caused by dust and sand in other desert regions. [125] Its most easterly point was at El Alamein in Egypt, where the Allies decisively defeated the Axis forces in 1942. This is a one-way letter exchange, so you will not receive a letter back. [14] The characteristics of hot deserts include high temperatures in summer; greater evaporation than precipitation, usually exacerbated by high temperatures, strong winds and lack of cloud cover; considerable variation in the occurrence of precipitation, its intensity and distribution; and low humidity. [97] Some arthropods make use of the ephemeral pools that form after rain and complete their life cycle in a matter of days. Most deserts are in basins with no drainage to the sea but some are crossed by exotic rivers sourced in mountain ranges or other high rainfall areas beyond their borders. [138], This article is about dry terrain. The smaller dune fields occupy the bottom of many of the craters situated in the Martian polar regions. Coastal deserts are mostly found on the western edges of continental land masses in regions where cold currents approach the land or cold water upwellings rise from the ocean depths. [95] The Saharan silver ant (Cataglyphis bombycina) uses a heat shock protein in a novel way and forages in the open during brief forays in the heat of the day. [85] The camel is a superb example of a mammal adapted to desert life. [100] A desert especially rich in mineral salts is the Atacama Desert, Chile, where sodium nitrate has been mined for explosives and fertilizer since around 1850. Orographic lift occurs as air masses rise to pass over high ground. This is because they reflect more of the incoming light and their albedo is higher than that of forests or the sea. This is believed to be caused by the stresses put on the rock by repeated thermal expansions and contractions which induces fracturing parallel to the original surface. These places owe their profound aridity (the average annual precipitation is often less than 40 mm or 1.5 in) to being very far from the nearest available sources of moisture and are often in the lee of mountain ranges. It has been portrayed by writers, film-makers, philosophers, artists and critics as a place of extremes, a metaphor for anything from death, war or religion to the primitive past or the desolate future. At greater wind speeds, some particles are lifted into the air stream. The upwind slope typically has a gradient of 10° to 20° while the lee slope is around 32°, the angle at which loose dry sand will slip.

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