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66-624: Escondida is a copper mine at 3,100 metres (10,200 ft) elevation in the Atacama Desert in Antofagasta Region , Chile . The Escondida deposit is one of a cluster of porphyry coppers in an elongated area about 18 km north–south and 3 km east–west and is associated with the 600 km long West Fissure ( Falla Oeste ) system, which is in turn associated with most of the major Chilean porphyry deposits. A barren, leached cap, in places up to 300 metres thick, overlies

132-456: A city is surrounded by hills or mountains since they form an additional barrier to air circulation. During a severe inversion, trapped air pollutants form a brownish haze that can cause respiratory problems. The Great Smog of 1952 in London , England, is one of the most serious examples of such an inversion. It was blamed for an estimated 10,000 to 12,000 deaths. Sometimes the inversion layer

198-424: A cooler one can "shut off" any convection which may be present in the cooler air mass: this is known as a capping inversion . However, if this cap is broken, either by extreme convection overcoming the cap or by the lifting effect of a front or a mountain range, the sudden release of bottled-up convective energy—like the bursting of a balloon—can result in severe thunderstorms. Such capping inversions typically precede

264-562: A group of British scientists have suggested that some river beds have been dry for 120,000 years. However, some locations in the Atacama receive a marine fog known locally as the camanchaca , providing sufficient moisture for hypolithic algae , lichens , and even some cacti —the genus Copiapoa is notable among these. Geographically, the aridity of the Atacama is explained by its being situated between two mountain chains (the Andes and

330-552: A land without men, where there is not a bird, not a beast, nor a tree, nor any vegetation. La Araucana by Alonso de Ercilla , 1569 In 2008, the Phoenix Mars Lander detected perchlorates on the surface of Mars at the same site where water was first discovered. Perchlorates are also found in the Atacama and associated nitrate deposits have contained organics, leading to speculation that signs of life on Mars are not incompatible with perchlorates. The Atacama

396-605: A much-prized resin, which the mining industry once harvested indiscriminately as fuel, making this plant endangered. The desert is also home to cacti, succulents, and other plants that thrive in a dry climate. Cactus species here include the candelabro ( Browningia candelaris ) and cardon ( Echinopsis atacamensis ), which can reach a height of 7 m (23 ft) and a diameter of 70 cm (28 in). The Atacama Desert flowering ( Spanish : desierto florido ) can be seen from September to November in years with sufficient precipitation, as happened in 2015. The climate of

462-412: A side effect of hotter air being less dense. Normally this results in distant objects being shortened vertically, an effect that is easy to see at sunset when the sun is visible as an oval. In an inversion, the normal pattern is reversed, and distant objects are instead stretched out or appear to be above the horizon, leading to the phenomenon known as a Fata Morgana or mirage . Inversions can magnify

528-546: A thick zone of high grade secondary supergene mineralisation of the main orebody, largely chalcocite and covellite , which in turn overlies the unaltered primary mineralisation of chalcopyrite , bornite and pyrite . At mid 2007, Escondida had total proven and probable reserves of 34.7 million tonnes of copper, of which 22.5 million tonnes is estimated to be recoverable. Total resources (including reserves) were 57.6 million tonnes of copper, of which 33.0 million tonnes should be recovered. Exploration continues. As of 2019,

594-499: A year. Moreover, some weather stations in the Atacama have never received rain. Periods up to four years have been registered with no rainfall in the central sector, delimited by the cities of Antofagasta , Calama , and Copiapó , in Chile. Evidence suggests that the Atacama may not have had any significant rainfall from 1570 to 1971. The Atacama Desert may be the oldest desert on earth, and has experienced hyper aridity since at least

660-560: Is also a testing site for the NASA-funded Earth–Mars Cave Detection Program . On 21 February 2023, scientists reported the findings of a "dark microbiome" of unfamiliar microorganisms in the Atacama Desert. In June 1991, Antofagasta and Taltal and inland regions as far as Calama received unusual rainfall leading to formation of a series of mudflows that killed 91 people. In 2012,

726-446: Is also crushed and dumped on large heaps, but here the leaching occurs through oxidation induced by microorganisms . The copper is also recovered by SX/EW. In 2006, 338.6 million tonnes were mined (928,000 tonnes per day), of which 251.5 million tonnes were waste and oxide ore. Sulphide ore totalled 87.1 million tonnes or 239,000 tonnes per day. The two camps, San Lorenzo and 2000, cater to 7,000 people daily. Escondida's current capacity

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792-424: Is around 1.4 million tonnes of copper production per year, making it the largest copper mine in the world. In 2005, Degrémont Industry was asked to install a new Sea Water Reverse Osmosis plant with capacity to produce 12 Million gallons of fresh water per day. Construction of work force accommodation camps and field offices are needed services in order to have the mine operating, on this note Tecno Fast in 2012

858-403: Is at a high enough altitude that cumulus clouds can condense but can only spread out under the inversion layer. This decreases the amount of sunlight reaching the ground and prevents new thermals from forming. As the clouds disperse, sunny weather replaces cloudiness in a cycle that can occur more than once a day. As the temperature of air increases, the index of refraction of air decreases,

924-491: Is instead refracted down towards the earth by the temperature-inversion boundary layer. This phenomenon is called tropospheric ducting . Along coastlines during Autumn and Spring, due to multiple stations being simultaneously present because of reduced propagation losses, many FM radio stations are plagued by severe signal degradation disrupting reception. In higher frequencies such as microwaves , such refraction causes multipath propagation and fading . When an inversion layer

990-666: Is like many of the small towns. Before the Inca Empire and prior to the arrival of the Spanish, the extremely arid interior was inhabited primarily by the Atacameño tribe. They are noted for building fortified towns called pucarás , one of which is located a few kilometers from San Pedro de Atacama. The town's church was built by the Spanish in 1577. The Atacameño were an extinct South American Indian culture, different from

1056-412: Is normally present) from happening in the affected area and can lead to high concentrations of atmospheric pollutants. Cities especially suffer from the effects of temperature inversions because they both produce more atmospheric pollutants and have higher thermal masses than rural areas, resulting in more frequent inversions with higher concentrations of pollutants. The effects are even more pronounced when

1122-470: Is one of the highest-growing wood species in the world. It is found at altitudes between 3,000 and 5,000 m (9,800 and 16,400 ft). Its dense form is similar to a pillow some 3 to 4 m (9.8 to 13.1 ft) thick. It concentrates and retains the heat from the day to cope with low evening temperatures. The growth rate of the llareta has been recently estimated at 1.5 cm/year (0.59 in/year), making many llaretas over 3,000 years old. It produces

1188-431: Is present, if a sound or explosion occurs at ground level, the sound wave is refracted by the temperature gradient (which affects sound speed) and returns to the ground. The sound, therefore, travels much better than normal. This is noticeable in areas around airports, where the sound of aircraft taking off and landing often can be heard at greater distances around dawn than at other times of day, and inversion thunder which

1254-404: Is recovered. It is piped down to the port of Coloso, where it is dewatered before shipping. Oxide ore, 4% of recoverable copper, is crushed, agglomerated and then acid leached in large heaps, and the copper is recovered from the leach solutions as copper cathode in a solvent extraction/electrowinning (SX/EW) plant. Recovery is 68%. The low grade sulfide ore contributes 19% of recoverable copper. It

1320-485: Is rich in metallic mineral resources such as copper, gold, silver and iron, as well as nonmetallic minerals including important deposits of boron, lithium, sodium nitrate, and potassium salts. The Salar de Atacama is where bischofite is extracted. These resources are exploited by various mining companies such as Codelco, Lomas Bayas, Mantos Blancos, and Soquimich. In recent years, large amounts of used clothing imported from overseas have begun to accumulate in portions of

1386-490: Is seasonally irrigated by melted snow. Vicuñas need to remain near a steady water supply, while guanacos can roam into more arid areas and survive longer without fresh water. South American fur seals and South American sea lions often gather along the coast. The Atacama is sparsely populated, with most towns located along the Pacific coast. In interior areas, oases and some valleys have been populated for millennia and were

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1452-404: Is the main topographical feature of the coast. The geomorphology of the Atacama Desert has been characterized as a low-relief bench "similar to a giant uplifted terrace" by Armijo and co-workers. The intermediate depression (or Central Valley) forms a series of endorheic basins in much of the Atacama Desert south of latitude 19°30'S. North of this latitude, the intermediate depression drains into

1518-509: Is the most prominent characteristic of the Atacama Desert. The Atacama Desert is commonly known as the driest place in the world, especially the surroundings of the abandoned Yungay mining town, where the University of Antofagasta Desert Research Station is located, in Antofagasta Region , Chile. The average rainfall is about 15 mm (0.6 in) per year, although some locations only receive 1 to 3 mm (0.04 to 0.12 in) in

1584-728: The Aymara to the north and the Diaguita to the south. The oasis settlement of Pica has Pre-hispanic origins and served as an important stopover for transit between the coast and the Altiplano during the time of the Inca Empire . The coastal cities originated in the 16th, 17th, and 18th centuries during the time of the Spanish Empire , when they emerged as shipping ports for silver produced in Potosí and other mining centers. At

1650-916: The CBI , the ASTE and the ACT , among others, have been operating in the Chajnantor area since 1999. On 26 April 2010, the ESO council decided to build a fourth site, Cerro Armazones , to be home to the Extremely Large Telescope . Construction work at the ELT site started in June 2014. The Carnegie Institution for Science operates the Las Campanas Observatory with several telescope in

1716-563: The McMurdo Dry Valleys . It is the only true desert to receive less precipitation than polar deserts , and the largest fog desert in the world. The area has been used as an experimentation site for Mars expedition simulations due to its similarities to the Martian environment. The constant temperature inversion caused by the cool north-flowing Humboldt ocean current and the strong Pacific anticyclone contribute to

1782-735: The Middle Miocene , since the establishment of a proto-Humboldt current in conjunction with the opening of the Tasmania-Antarctic passage ca. 33  Ma . The opening of the Tasmania-Antarctic passage allowed for cold currents to move along the west coast of South America, which influenced the availability of warm humid air to travel from the Amazon Basin to the Atacama. Though there was a general lack of humid air after 33 Ma, there were punctuated intervals of increased humidity, such as between around 10.86 and 6.4 Ma, when

1848-520: The War of the Pacific . The desert is littered with about 170 abandoned nitrate (or "saltpeter") mining towns, almost all of which were shut down decades after the invention of synthetic nitrate in Germany in the first decade of the 20th century (see Haber process ). The towns include Chacabuco , Humberstone, Santa Laura , Pedro de Valdivia, Puelma, María Elena , and Oficina Anita. The Atacama Desert

1914-465: The lomas , where it lays eggs in permanent ponds or streams. Iguanians and lava lizards inhabit parts of the desert, while salt flat lizards, Liolaemus , live in the dry areas bordering the ocean. One species, Liolaemus fabiani , is endemic to the Salar de Atacama , the Atacama salt flat. Birds are one of the most diverse animal groups in the Atacama. Humboldt penguins live year-round along

1980-414: The 18th and 19th centuries resulted in widespread deforestation . In a region about 100 km (60 mi) south of Antofagasta, which averages 3,000 m (10,000 ft) in elevation, the soil has been compared to that of Mars . Owing to its otherworldly appearance, the Atacama has been used as a location for filming Mars scenes, most notably in the 2004 television series Space Odyssey: Voyage to

2046-505: The Atacama Crossing has the competitors cross the various landscapes of the Atacama. Inversion (meteorology) In meteorology , an inversion (or temperature inversion ) is a phenomenon in which a layer of warmer air overlies cooler air. Normally, air temperature gradually decreases as altitude increases, but this relationship is reversed in an inversion. An inversion traps air pollution , such as smog , near

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2112-401: The Atacama Desert limits the number of animals living permanently in this extreme ecosystem. Some parts of the desert are so arid, no plant or animal life can survive. Outside of these extreme areas, sand-colored grasshoppers blend with pebbles on the desert floor, and beetles and their larvae provide a valuable food source in the lomas (hills). Desert wasps and butterflies can be found during

2178-549: The Chilean Coast Range) of sufficient height to prevent moisture advection from either the Pacific or the Atlantic Oceans, a two-sided rain shadow. Despite modern views of the Atacama Desert as fully devoid of vegetation, in pre-Columbian and colonial times a large flatland area there known as Pampa del Tamarugal was a woodland , but demand for firewood associated with silver and saltpeter mining in

2244-485: The Chilean state. Miners and mining companies came into conflict, and protests spread throughout the region. Around 1900, there were irrigation system of puquios spread through the oases of Atacama Desert. Puquios are known from the valleys of Azapa and Sibaya and the oases of La Calera , Pica - Matilla and Puquio de Núñez . In 1918, geologist Juan Brüggen mentioned the existence of 23 socavones (shafts) in

2310-550: The Pacific Ocean. In December 2023, scientists, for the first time, reported on a recently discovered area in the territory of Puna de Atacama , which may have similarities to Earth during the Archean eon and thus to the environment of the first life forms on Earth . It could as well be similar to conceivably-hospitable conditions on the planet Mars during earlier Martian times. The almost total lack of precipitation

2376-455: The Pica oasis, yet these have since been abandoned due to economic and social changes. The desert has rich deposits of copper and other minerals and the world's largest natural supply of sodium nitrate (Chile saltpeter), which was mined on a large scale until the early 1940s. The Atacama border dispute over these resources between Chile and Bolivia began in the 19th century and resulted in

2442-506: The Planets . In 2003, a team of researchers published a report in which they duplicated the tests used by the Viking 1 and Viking 2 Mars landers to detect life and were unable to detect any signs in Atacama Desert soil in the region of Yungay. The region may be unique on Earth in this regard and is being used by NASA to test instruments for future Mars missions. The team duplicated

2508-554: The Tiliviche Palaeolake existed before turning into a salar sometime before the Middle Pliocene. The long history of aridity raises the possibility that supergene mineralisation , under the appropriate conditions, can form in arid environments, instead of requiring humid conditions. The presence of evaporite formations suggests that in some sections of the Atacama Desert, arid conditions have persisted for

2574-521: The Viking tests in Mars-like Earth environments and found that they missed present signs of life in soil samples from Antarctic dry valleys , the Atacama Desert of Chile and Peru, and other locales. However, in 2014, a new hyperarid site was reported, María Elena South, which was much drier than Yungay and, thus, a better Mars-like environment. Towards Atacama, near the deserted coast, you see

2640-483: The altiplano winter brought floods to San Pedro de Atacama . On 25 March 2015, heavy rainfall affected the southern part of the Atacama Desert. Resulting floods triggered mudflows that affected the cities of Copiapo , Tierra Amarilla , Chanaral , and Diego de Almagro , causing the deaths of more than 100 people. In spite of the geographic and climatic conditions of the desert, a rich variety of flora has evolved there. Over 500 species have been gathered within

2706-474: The atmosphere is heated from below as solar radiation warms the Earth's surface, which in turn then warms the layer of the atmosphere directly above it, e.g., by thermals ( convective heat transfer ). Air temperature also decreases with an increase in altitude because higher air is at lower pressure, and lower pressure results in a lower temperature, following the ideal gas law and adiabatic lapse rate . Under

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2772-413: The border of this desert. These species are characterized by their extraordinary ability to adapt to this extreme environment. The most common species are herbs and flowers such as thyme , llareta , and saltgrass ( Distichlis spicata ), and where humidity is sufficient, trees such as the chañar ( Geoffroea decorticans ), the pimiento tree, and the leafy algarrobo ( Prosopis chilensis ). The llareta

2838-401: The coast, nesting in desert cliffs overlooking the ocean. Inland, high-altitude salt flats are inhabited by Andean flamingos , while Chilean flamingos can be seen along the coast. Other birds (including species of hummingbirds and rufous-collared sparrow ) visit the lomas seasonally to feed on insects, nectar, seeds, and flowers. The lomas help sustain several threatened species, such as

2904-499: The cooler layer, fog is typically present below the inversion cap. An inversion is also produced whenever radiation from the surface of the earth exceeds the amount of radiation received from the sun, which commonly occurs at night, or during the winter when the sun is very low in the sky. This effect is virtually confined to land regions as the ocean retains heat far longer. In the polar regions during winter, inversions are nearly always present over land. A warmer air mass moving over

2970-658: The desert experiences more than 200 cloudless nights each year. A number of telescopes have been installed to help astronomers from across the globe study the universe. A radio astronomy telescope, called the Atacama Large Millimeter Array , built by European countries, Japan , the United States , Canada , and Chile in the Llano de Chajnantor Observatory officially opened on 3 October 2011. A number of radio astronomy projects, such as

3036-420: The desert, and cities along the coast developed into international ports, hosting many Chilean workers who migrated there. With the guano and saltpeter booms of the 19th century, the population grew immensely, mostly as a result of immigration from central Chile. In the 20th century, the nitrate industry declined and at the same time, the largely male population of the desert became increasingly problematic for

3102-468: The desert. Because of the dry conditions, they do not decompose at the normal rate, and fires have exposed nearby residents to air pollution. Because of its high altitude, nearly nonexistent cloud cover, dry air, and freedom from light pollution and radio interference from widely populated cities and towns, this desert is one of the best places in the world to conduct astronomical observations. Hundreds of thousands of stars can be viewed via telescope since

3168-525: The development of tornadoes in the Midwestern United States . In this instance, the "cooler" layer is quite warm but is still denser and usually cooler than the lower part of the inversion layer capping it. An inversion can develop aloft as a result of air gradually sinking over a wide area and being warmed by adiabatic compression, usually associated with subtropical high-pressure areas . A stable marine layer may then develop over

3234-477: The end of the 18th century, Carlos IV defines the southern border of the Viceroyalty of Peru at the port of Nuestra Señora del Paposo. During the 19th century, the desert came under control of Bolivia, Chile, and Peru. With the discovery of sodium nitrate deposits and as a result of Chilean expansion plans, the area soon became a zone of conflict and resulted in the War of the Pacific . Chile annexed most of

3300-478: The endangered Chilean woodstar . Because of the desert's extreme aridity, only a few specially adapted mammal species live in the Atacama, such as Darwin's leaf-eared mouse . The less arid parts of the desert are inhabited by the South American gray fox and the viscacha (a relative of the chinchilla ). Larger animals, such as guanacos and vicuñas , graze in areas where grass grows, mainly because it

3366-661: The extreme aridity of the desert. The most arid region of the Atacama Desert is situated between two mountain chains, the Andes and the Chilean Coast Range , which are high enough to prevent moisture advection from either the Pacific or the Atlantic Ocean, creating a two-sided rain shadow effect. According to the World Wide Fund for Nature , the Atacama Desert ecoregion occupies a continuous strip for nearly 1,600 kilometres (1,000 mi) along

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3432-468: The ground. An inversion can also suppress convection by acting as a "cap". If this cap is broken for any of several reasons, convection of any humidity can then erupt into violent thunderstorms . Temperature inversion can cause freezing rain in cold climates . Usually, within the lower atmosphere (the troposphere ) the air near the surface of the Earth is warmer than the air above it, largely because

3498-488: The highest peaks (such as Ojos del Salado , Monte Pissis , and – debatably – Llullaillaco ) have some permanent snow coverage. The southern part of the desert, between 25° and 27°S, may have been glacier-free throughout the Quaternary (including during glaciations ), though permafrost extends down to an altitude of 4,400 m (14,400 ft) and is continuous above 5,600 m (18,400 ft). Studies by

3564-402: The known resource is 21.7 Billion tonnes at 0.54 percent Copper including Escondida and adjacent deposits. The mine and ancillary industries contributes 2.5% to Chile’s GDP. Sulfide ore, which contributes 77% of the recoverable copper reserve, is crushed and milled in one of the two concentrators and the copper concentrate is separated out using froth flotation . Approximately 86% of the copper

3630-626: The last 200 million years (since the Triassic ). Aridity in Atacama Desert predates the rise of the Central Andes, yet hyper-aridity is generally thought to have resulted from the rise of the Andes. As such it is hypothesised it had climatic conditions akin to the Namib Desert prior to the rise of the mountains. The Atacama is so arid that many mountains higher than 6,000 m (20,000 ft) are completely free of glaciers . Only

3696-605: The location of the most advanced pre-Columbian societies found in Chile. The Chinchorro culture developed in the Atacama Desert area from 7000 BCE to 1500 BCE. These peoples were sedentary fishermen inhabiting mostly coastal areas. Their presence is found from today's towns of Ilo , in southern Peru, to Antofagasta in northern Chile. Presence of fresh water in the arid region on the coast facilitated human settlement in these areas. The Chinchorro were famous for their detailed mummification and funerary practices. San Pedro de Atacama , at about 2,400 m (8,000 ft) elevation,

3762-577: The narrow coast of the northern third of Chile , from near Arica (18°24′S) southward to near La Serena (29°55′S). The National Geographic Society considers the coastal area of southern Peru to be part of the Atacama Desert and includes the deserts south of the Ica Region in Peru. However, other sources consider that the part of the desert in Peru is a different ecosystem, and should properly be named as Pampas de la Joya desert. Peru borders it on

3828-708: The north and the Chilean Matorral ecoregion borders it on the south.To the east lies the less arid Central Andean dry Puna ecoregion. The drier portion of this ecoregion is located south of the Loa River between the parallel Sierra Vicuña Mackenna and the Cordillera Domeyko . To the north of the Loa lies the Pampa del Tamarugal . The Coastal Cliff of northern Chile west of the Chilean Coast Range

3894-493: The north of Chile . Stretching over a 1,600-kilometre-long (1,000-mile) strip of land west of the Andes Mountains , it covers an area of 105,000 km (41,000 sq mi), which increases to 128,000 km (49,000 sq mi) if the barren lower slopes of the Andes are included. The Atacama Desert is the driest nonpolar desert in the world, and the second driest overall, behind some specific spots within

3960-461: The ocean as a result. As this layer moves over progressively warmer waters, however, turbulence within the marine layer can gradually lift the inversion layer to higher altitudes, and eventually even pierce it, producing thunderstorms, and under the right circumstances, tropical cyclones . The accumulated smog and dust under the inversion quickly taints the sky reddish, easily seen on sunny days. Temperature inversions stop atmospheric convection (which

4026-546: The right conditions, the normal vertical temperature gradient is inverted so that the air is colder near the surface of the Earth. This can occur when, for example, a warmer, less-dense air mass moves over a cooler, denser air mass. This type of inversion occurs in the vicinity of warm fronts , and also in areas of oceanic upwelling such as along the California coast in the United States. With sufficient humidity in

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4092-655: The so-called " green flash "—a phenomenon occurring at sunrise or sunset, usually visible for a few seconds, in which the sun's green light is isolated due to dispersion. The shorter wavelength is refracted most, with the blue component of sunlight "completely scattered out by Rayleigh scattering ", making green the first or last light from the upper rim of the solar disc to be seen. Very high frequency radio waves can be refracted by inversions, making it possible to hear FM radio or watch VHF low -band television broadcasts from long distances on foggy nights. The signal, which would normally be refracted up and away into space,

4158-476: The southern portion of the desert. The European Southern Observatory operates three major observatories in the Atacama and is currently building a fourth: The Atacama Desert is popular with all-terrain sports enthusiasts. Various championships have taken place here, including the Lower Atacama Rally, Lower Chile Rally, Patagonia-Atacama Rally, and the latter Dakar Rally 's editions. The rally

4224-457: The warm and humid season, especially on the lomas. Red scorpions also live in the desert. A unique environment is provided by some lomas , where the fog from the ocean provides enough moisture for seasonal plants and a few animal species. Surprisingly few reptile species inhabit the desert and even fewer amphibian species. Chaunus atacamensis , the Vallenar toad or Atacama toad, lives on

4290-537: Was hired to build the second phase of the respective workforce accommodation camp for Escondida Mine. BHP buys 3 TWh of electricity per year to operate the Escondida and Spence mines (1.640 m elevation), where solar energy is more than 3.000 kWh/m per year. Atacama Desert The Atacama Desert ( Spanish : Desierto de Atacama ) is a desert plateau located on the Pacific coast of South America , in

4356-630: Was organized by the Amaury Sport Organisation and held in 2009, 2010, 2011, and 2012. The dunes of the desert are ideal rally races located in the outskirts of the city of Copiapó. The 2013 Dakar 15-Day Rally started on 5 January in Lima, Peru, through Chile, Argentina and back to Chile finishing in Santiago. Visitors also use the Atacama Desert sand dunes for sandboarding ( Spanish : duna ). A week-long foot race called

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