147 Fun Facts About Deserts

What does a camel's hump actually store?

Fat, not water: the hump is an energy reserve, and it goes limp and droops to one side as the camel uses it up when food is scarce.

Which non-polar desert is widely considered the driest on Earth?

The Atacama Desert in South America receives extremely little rainfall, with some areas experiencing virtually no recorded precipitation, making it the driest non-polar desert.

Asia's Gobi Desert is classed as which type of desert?

Cold winter: the Gobi lies deep inside Asia, hundreds of kilometres from any ocean, so winds arrive already wrung dry; frost and even snow can settle on its dunes.

Which feature helps desert animals shed excess heat?

Large ears work as radiators: when the blood vessels in them widen, warm blood spreads over a big surface and its heat escapes into the air, which is how desert hares keep cool.

What is the general term for plants that store water in thickened, fleshy stems, leaves or roots?

Succulents keep water in swollen leaves, stems or roots; cacti are succulents, but many succulents, such as the jade plant, are not cacti.

What phenomenon often creates deserts on the leeward side of mountain ranges?

Rain shadow effect: air descending the leeward slope is compressed and warmed, so it holds on to its moisture; the Himalayas cast such a shadow over the Gobi.

What do you call a fertile, watered pocket in the middle of a desert?

An oasis is usually fed from underground: its springs and wells tap aquifers whose water may have fallen as rain hundreds of kilometres away.

What does the term 'desertification' describe?

Fertile dryland degrading into desert is what the UN convention means by the word; it stresses that the damage comes from human activity and climate swings, not from existing deserts naturally spreading.

Which two deserts are larger than the Sahara?

Antarctica and the Arctic count as deserts because so little rain or snow falls there; Antarctica alone covers about 14 million square kilometres, far more than the Sahara.

What is the dark reddish-brown to black coating on exposed desert rocks called?

Desert varnish is a thin mineral coating of clay with iron and manganese oxides; many desert petroglyphs were made by carving through the dark layer to the paler rock beneath.

In which desert does the giant saguaro cactus grow wild?

Sonoran Desert: wild saguaros grow only in Arizona, the Mexican state of Sonora and a sliver of south-eastern California; the Tohono O'odham turn the red fruit into syrup.

What single measure decides whether a place counts as a desert?

Very low annual precipitation is the test, usually under about 250 mm a year, not heat or sand: most desert is bare rock, gravel or mountain, with dunes covering only a small share.

What is the main advantage of nocturnal activity for desert animals?

To avoid heat and so conserve water: an animal that sleeps through the scorching day and forages in the cool of night loses far less moisture to evaporation.

Which of these deserts is located in South America?

Bounded by the Andes to the west and the Atlantic to the east, the Patagonian Desert was once forested: volcanic ash buried the trees and minerals turned the trunks to stone, leaving vast petrified forests.

Desert pavement, a surface of tightly packed stones, is traditionally explained by which process?

Wind erosion (deflation) is the classic account: the wind carries off the sand and silt and leaves a lag of packed stones, though some pavements are now thought to rise on dust trapped beneath them.

Every 20,000 years or so the Sahara flips between desert and what, due to Earth's wobble?

Savanna grassland: precession shifts where the North African monsoon falls, so a 'Green Sahara' of grass, lakes and hippos returns on a roughly 20,000-year cycle.

Which desert is known for holding the record for the highest air temperature ever recorded on Earth?

Death Valley reached 56.7°C (134°F) at Furnace Creek on 10 July 1913, yet it became the official record holder only in 2012, when the WMO struck out a higher 1922 reading from North Africa.

How does the desert kangaroo rat manage to live almost without drinking?

Metabolic water from seeds plus concentrated urine: its body releases water as it breaks down dry seeds, and its kidneys pass very little of it back out.

The Spanish name of which Mojave Desert city means 'the meadows'?

Las Vegas takes its name from the spring-fed grassy meadows that traders on the trail to California found in the valley in 1829; they have long since been buried under streets and car parks.

Which crescent-shaped sand formation has 'horns' pointing downwind?

A barchan creeps downwind as sand blows up its gentle back and slides down the steep face between the horns; crescent dunes like it move faster than any other type.

What are the Kelso Dunes of California's Mojave Desert known for when their sand avalanches?

Giving off a low booming hum: as sand slides down a steep face it sets up a deep rumble that can be felt as well as heard, and it takes smooth, rounded grains and thoroughly dry sand to make it.

Desert plants that complete their whole life cycle in a brief spell after rain are called what?

Ephemerals turn normally bare Namaqualand in South Africa into a carpet of flowers each spring, after the winter rains.

What are dry desert lakebeds that temporarily fill with water after rain called?

Playas form where rain collects in a desert basin: the shallow lake evaporates and leaves another layer of salt and mud, which is why they end up so flat. The name is Spanish for 'beach'.

Which city on the Sahara's southern edge became an English byword for the middle of nowhere?

Timbuktu was in truth a rich medieval hub where caravans traded Saharan salt for gold, and a famed centre of Islamic learning; only later did its name come to mean somewhere impossibly remote.

What do desert scorpions do under ultraviolet light?

Glow blue-green: chemicals in a scorpion's outer shell fluoresce under ultraviolet light, so researchers go looking for them at night with a black light.

What is a 'wadi' in a desert environment?

A riverbed that carries water only after heavy rain, a wadi can turn into a flash flood within minutes, then empty again as the water sinks into its porous bed.

How do cacti keep their water loss so low?

Waxy cuticles and spines in place of leaves: with no leaf surface to lose water from, a cactus makes its food in the green stem, sealed under a thick waxy skin.

The Great Basin Desert, known for its sagebrush, is located on which continent?

North America: the Great Basin Desert owes its name to a quirk of drainage, for none of its rivers reaches the sea; their water ends in closed valleys, salt lakes and dry sinks.

What Arabic-derived term names a barren, rocky desert plateau stripped of sand?

Hamada is the Arabic term for a hard, barren rocky plateau from which the wind has stripped the sand; bare rock like this covers far more of the Sahara than dunes, which make up only about a quarter of it.

Which Arabian desert is known in English as the 'Empty Quarter'?

Rub' al Khali covers some 650,000 square kilometres of southern Arabia; empty it may look, but part of Ghawar, the world's largest conventional oil field, lies beneath its northern sands.

What is a common adaptation for desert animals to escape the most extreme daytime temperatures?

Living in underground burrows works because soil insulates: a little way down it stays far cooler and more humid than the surface, so a resting animal loses less water.

The Dasht-e Lut, where satellites have logged some of Earth's hottest ground temperatures, lies in which country?

Iran: no weather station stands in the Lut, so the figures come from NASA satellites, which read the skin of its dark ground at 70.7°C in 2005, far hotter than any air temperature on record.

What wind-carved ridges run parallel to the prevailing wind where softer rock has been worn away?

Yardangs take their name from a Turkic word for a steep bank; from above they look like upturned boat hulls, and the Great Sphinx of Giza may itself be a yardang that sculptors finished.

Cacti open their stomata to take in CO2 mainly at what time of day, sharply cutting water loss?

After dark, via crassulacean acid metabolism: CO2 is stored overnight and used once the sun is up, separating gas exchange from photosynthesis.

The Thar Desert is primarily located in which two countries?

India and Pakistan: most of the Thar Desert lies on the Indian side, where the long Indira Gandhi Canal now brings river water in and has turned stretches of bare sand into farmland.

Which icon of Hollywood Westerns is in fact an invasive plant that reached America from Russia?

Tumbleweed, or Russian thistle, is native to Eurasia and reached the American West by accident in imported seed; each dead plant snaps off at the base and rolls with the wind, scattering seeds as it goes.

Which of these is a major cause of desertification?

Overgrazing and deforestation strip away the plants that anchor dry soil, so wind and rain carry the topsoil off; in the Sahel such damage helped turn the droughts of the 1970s and 1980s into famine.

The Danakil Depression, one of the hottest places on Earth, is found in which region?

Horn of Africa: the Danakil Depression lies in Ethiopia and Eritrea and sinks more than 100 m below sea level; it was once covered by an inland sea, which evaporated and left thick beds of salt.

What is the primary reason for the large temperature difference between day and night in many deserts?

Lack of cloud cover and humidity leaves nothing to hold the day's heat in: after sunset the ground radiates it straight back to the sky, and a scorching day can end only a few degrees above freezing.

Which is the largest desert in Australia?

The Great Victoria Desert was named in 1875 by the explorer Ernest Giles for the reigning queen; in the 1950s Britain tested atomic bombs at Maralinga inside it, contaminating the land.

What are 'inselbergs' in a desert landscape?

Isolated hills rising abruptly from a plain, inselbergs are made of tougher rock left standing as the land around them wore down; the German name means 'island mountain', and Uluru is the best-known example.

Why do many desert plants have broad, shallow roots?

To quickly capture widely dispersed rainfall: desert showers are brief and wet only the top of the soil, so a cactus spreads its roots just under the surface and drinks before the water is gone.

Which of these deserts is located in Central Asia?

The Kara-Kum Desert lies in Central Asia east of the Caspian Sea; a canal more than 1,300 km long was dug across it in Soviet times to carry river water to its farms.

What is the scientific term for plants that are adapted to live in extremely dry conditions?

Xerophytes, from the Greek for 'dry' and 'plant', range from cacti to resurrection plants, which can dry out almost completely, shut down for years, and unfurl again within hours of getting wet.

Wadi Rum, the 'Valley of the Moon' seen in Lawrence of Arabia, is in which country?

Jordan's Wadi Rum has been a UNESCO World Heritage site since 2011, and its red cliffs keep finding film work: after Lawrence of Arabia it played Mars in The Martian and the planet Arrakis in Dune.

What causes the phenomenon of a 'mirage' in deserts?

Atmospheric refraction of light bends rays from the sky as they cross the hot air just above the ground, so the shimmering 'water' on the horizon is really a displaced image of the sky.

The 1879 War of the Pacific was fought over the Atacama's rich deposits of which fertiliser mineral?

Nitrates: Chile won the war and the saltpetre fields, and export taxes on this 'white gold' paid half its government's bills until German chemists learned to make nitrogen fertiliser from air.

What do geologists call the sandblasting of rock by wind-blown sand?

Abrasion works close to the ground, because the wind rarely lifts sand grains more than a metre or two; over time it cuts and polishes exposed stones into faceted 'ventifacts'.

What do meteorologists call the towering wall of dust a thunderstorm's outflow drives across a desert?

A haboob forms when a thunderstorm's cold downdraft hits the ground and rushes outward, scooping up a wall of dust ahead of the rain; the Arabic name was first used of such storms in Sudan.

Southwest Africa's bizarre Welwitschia plant grows how many leaves in its whole life?

Two: the pair of strap-like leaves keeps growing from the base for the plant's whole life, fraying at the tips into a tangled heap, and the oldest plants may be around 2,000 years old.

How does southwest Africa's fog-basking beetle get a drink?

Headstands so drops run to its mouth: on foggy nights the beetle climbs a dune, tips its rear end into the wind, and lets the mist that condenses on its body trickle down to be drunk.

China's Taklamakan Desert fills which great inland basin?

Tarim Basin: the Taklamakan fills its floor, ringed by the Kunlun, Pamir and Tian Shan ranges, and was so feared that the Silk Road split in two to skirt its northern and southern edges.

What happened at Lop Nur, a dried salt lake in Xinjiang, on 16 October 1964?

China's first nuclear bomb test was code-named 596 after June 1959, the month Moscow withdrew its promised help and Beijing resolved to build the bomb alone; the 22-kiloton device was fired from a tower.

Australia's Simpson Desert holds which world record?

Longest parallel sand dunes: the ridges run side by side for up to 160 km, pinned in place by vegetation, though even the biggest, Big Red, stands only about 40 m high.

What gives Uluru its famous red colour?

Rusting iron in the rock: fresh Uluru sandstone is grey, as its caves still show, and only the weathered skin has oxidised red; the rock stands 348 m high, with most of its bulk hidden underground.

What moves the 'sailing stones' that leave trails across California's Racetrack lakebed?

Thin ice sheets nudged by light winds: researchers reported in 2014 that they had watched a winter pond freeze into panes a few millimetres thick, which broke up in a breeze and shoved the rocks along at a few metres a minute.

New Mexico's brilliant White Sands dunes are made of which mineral?

Gypsum: rain and snowmelt dissolve it from the surrounding mountains and carry it into the Tularosa Basin, where Lake Lucero dries out and the crystals weather into white sand.

The tallest sand dunes in North America are in which US state?

Colorado: at Great Sand Dunes National Park the prevailing winds sweep sand across the San Luis Valley and pile it against the Sangre de Cristo mountains, building dunes more than 700 feet high.

Which bird of the American Southwest's deserts is a cuckoo that would sooner sprint than fly?

Roadrunners belong to the cuckoo family and can run at 15 to 20 mph, taking to the air only when they must; they are quick enough to catch lizards, scorpions and even young rattlesnakes.

Who is traditionally said to have named the Mojave's Joshua tree?

Mormon colonists crossing the Mojave in the mid-1800s are said to have seen Joshua lifting his hands in prayer in the upraised branches, though no contemporary record of the story exists.

Why was the ALMA telescope array built 5,000 m up in the Atacama?

Dry, thin air lets signals through: the faint millimetre waves ALMA collects are soaked up by water vapour, so its 66 dishes sit above most of it, where the antenna-transporter drivers breathe bottled oxygen.

How were the 33 miners trapped beneath the Atacama rescued in 2010?

One by one in a narrow capsule: after 69 days underground the men of Chile's San José mine were winched up a newly drilled rescue shaft; weeks earlier a note sent up on a drill had told the world all 33 were alive.

How were Peru's Nazca Lines drawn on the desert floor?

By scraping away dark surface stones: lifting the reddish, iron-coated pebbles exposes pale ground beneath, and with almost no rain or wind on the plateau the lines have lasted some 2,000 years.

The Richat Structure, the ringed 'Eye of the Sahara' seen from space, is in which country?

Mauritania: the rings of the Richat Structure are beds of hard quartzite, left standing as circular ridges while the weaker layers between them wore away.

Dust from the Sahara's Bodélé Depression is credited with fertilising which distant ecosystem?

Amazon rainforest: the dust is the remains of microscopic creatures from the bed of a vanished mega-lake, rich in phosphorus, and the wind carries it across the Atlantic to feed the basin's nutrient-poor soils.

Tassili n'Ajjer, the Saharan plateau famed for prehistoric rock art, is in which country?

Algeria: Tassili n'Ajjer, a UNESCO site since 1982 in the country's far south-east, holds more than 15,000 drawings and engravings, among them cattle herds and crocodiles that record how the climate here has changed.

Which Saharan animal is the smallest of all fox species?

Fennec fox: weighing only about 1.5 kg, it is the smallest fox of all, and the pads of its paws are covered in dense fur so that it can walk on scorching sand.

Which reptile of the American Southwest is the only venomous lizard native to the United States?

Gila monster: its venom, made in glands in the lower jaw, held a gift for medicine, for a hormone discovered in it led to the diabetes drug exenatide.

How does Australia's thorny devil lizard take a drink?

Water wicks along skin grooves to its mouth by capillary action, so the lizard only has to stand in damp sand or let dew settle on its back to take a drink.

Which small rattlesnake of the American Southwest has horn-like scales above its eyes?

Sidewinder: it throws its body sideways in loops, so that only short stretches touch the hot, loose sand at any moment, a gait engineers have copied to help snake robots climb sandy slopes.

Mongolia's Flaming Cliffs, a Velociraptor fossil site, were named by which 1920s explorer?

Roy Chapman Andrews, leading the American Museum of Natural History's Gobi expeditions, named the red cliffs in the 1920s, and it was there that his team found the first known dinosaur eggs.

Israel's vast Ramon Crater in the Negev was formed how?

By erosion of a collapsed dome: Ramon is no meteorite or volcanic crater; water cut through the hard limestone cap of an upfolded ridge, washed out the soft sandstone beneath and let the roof fall in.

The Dead Sea Scrolls were found in caves near Qumran in which desert?

Judaean Desert: Qumran sits on its eastern edge above the north-western end of the Dead Sea, where a Bedouin boy hunting for a lost animal stumbled on the first cave in late 1946 or early 1947.

The 'Door to Hell', a gas crater set alight decades ago, is in which Central Asian country?

Turkmenistan: by the usual account Soviet engineers set the Darvaza crater alight in 1971 to burn off escaping gas, though local geologists date the fire to the 1980s; in 2022 the president ordered it put out.

What does the name of Central Asia's Kyzylkum Desert mean?

Red Sand: kyzyl means 'red' and kum 'sand' in the Turkic languages, and those sands are dug for gold at Muruntau, one of the world's largest open-pit mines.

The Aralkum, often called the world's youngest desert, has formed on a dried seabed in which two countries?

Uzbekistan and Kazakhstan: the Aralkum appeared as Soviet irrigation schemes starved the Aral Sea of its inflow; Kazakhstan's Kok-Aral Dam, finished in 2005, revived only the small northern lobe.

The Tabernas Desert, often called Europe's only true desert, is in which country?

Spain: the Tabernas Desert lies in Almería province in Andalusia, where spaghetti westerns such as the Dollars trilogy were shot and the Plataforma Solar de Almería tests solar-thermal power.

The Pinnacles Desert's thousands of limestone pillars stand in which Australian state?

Western Australia: the pillars stand in Nambung National Park near the coastal town of Cervantes; they began as seashells, ground into lime-rich sand that blew inland as dunes and hardened into limestone.

India's 1998 nuclear tests at Pokhran were carried out in which desert state?

Rajasthan's Pokhran range saw five devices fired on 11 and 13 May 1998; to dodge American spy satellites the crews worked mostly at night and parked their equipment back in the same spots by dawn.

Emi Koussi, the highest mountain in the Sahara, is a volcano in which country?

Chad: Emi Koussi crowns the Tibesti range in the country's far north as the highest point of the whole Sahara, and planetary scientists study its broad summit crater as a stand-in for a volcano on Mars.

The Sahel, the Sahara's southern fringe, takes its name from an Arabic word meaning what?

Shore: the Arabic sahil means 'coast' or 'shore', the image being the Sahara as a sea with the Sahel as its southern beach.

Alexander the Great trekked across the Egyptian desert to consult the oracle of Amun at which oasis?

Siwa: by one ancient account two ravens led Alexander across the sands, by another two snakes; once he arrived, the oracle's priest greeted him as the son of the god Ammon.

Petra, the rock-cut 'Rose City', became the capital of which ancient people?

Nabataeans: these nomadic Arab traders settled Petra by the 4th century BC, grew rich on the incense routes and engineered cisterns and conduits to survive the desert.

The Dakar Rally, born as a Paris–Dakar dash, moved to which country in 2020?

Saudi Arabia: after terrorist threats forced the 2008 race to be cancelled, the rally ran in South America from 2009 to 2019 before moving to Saudi Arabia in 2020.

The Marathon des Sables, a six-stage ultramarathon since 1986, is run in which country's Sahara?

Morocco: runners cover about 250 km of the Moroccan Sahara south of the Atlas Mountains over six stages carrying their own food; the first edition in 1986 had just 23 competitors.

What keeps Antarctica's McMurdo Dry Valleys almost entirely free of snow?

Katabatic winds: cold, dense air pours downhill off the ice sheet, drying as it falls, and scours the snow away, while the mountains around the valleys hold the glaciers back.

What do geographers call a desert 'sand sea', a vast expanse of wind-blown dunes?

Erg, from the Arabic for 'dune field': the Sahara's great sand seas such as the Grand Erg Oriental are ergs, while most of the desert is rock and gravel.

Burning Man is staged on a dry lakebed in which US state?

Nevada: the festival began in 1986 on a San Francisco beach and moved to the desert in 1990 after park police stopped the burn; tens of thousands now build a temporary city there and aim to leave no trace.

ThrustSSC broke the sound barrier on land in 1997 on which dry lakebed?

Black Rock Desert: on 15 October 1997 RAF pilot Andy Green took the twin-jet car to 763 mph, a figure averaged, as the rules demand, over two runs in opposite directions made within an hour.

Star Wars' desert planet Tatooine was filmed largely in which country?

Tunisia: Tatooine's scenes were shot around Matmata and the island of Djerba in 1976, and George Lucas took the planet's name from the real Tunisian town of Tataouine.

Mad Max: Fury Road's desert chases were moved from rain-greened Australia to which country?

Namibia: unexpected rain made wildflowers bloom around Broken Hill, the planned outback location, so the shoot moved in 2012 to the dunes of Dorob National Park on Namibia's coast.

What did the Chinchorro people of the Atacama coast begin doing to their dead some 7,000 years ago?

Mummifying them: from about 5050 BC the Chinchorro took bodies apart and rebuilt them with clay and paint, long before Egypt's mummies, and they did it for men, women and children alike, not just an elite.

For 90 years the world heat record was a 58°C reading taken in 1922 at 'Aziziya, in which country?

Libya: in 2012 the World Meteorological Organization struck the 'Aziziya reading from the books, concluding that an inexperienced observer had probably misread an unfamiliar instrument.

Which landscape of sandstone buttes on the Arizona–Utah border became the backdrop of John Ford's Westerns?

Monument Valley lies within the Navajo Nation; Ford first filmed there for his 1939 Western Stagecoach and came back so often that its buttes became moviegoers' picture of the American West.

The name Kalahari is usually traced to a Tswana word meaning what?

The great thirst is the usual reading of the Tswana kgala, though some trace the name to Kgalagadi, 'a waterless place'; yet seasonal rain feeds enough grass and scrub that much of the Kalahari is not true desert.

Why are the Sahara's Tuareg sometimes called the 'Blue People'?

Indigo from their veils tints their skin: the dye in the tagelmust rubs off on the wearer, and unusually it is the men who veil their faces while women traditionally go unveiled.

The Harmattan, a dry, dusty wind off the Sahara, blows over which region each winter?

West Africa: from late November to mid-March the Harmattan haze blows south-west from the Sahara over Nigeria, Ghana and their neighbours, grounding flights and cutting visibility as far as the Gulf of Guinea.

What does a camel's hump actually hold in reserve for long desert journeys when food runs short?

Fatty tissue fills a camel's hump, a store of calories the animal burns through in lean times. The idea that the hump is a water tank is a myth.

Which river flows north through the Sahara's Nubian Desert to reach the Mediterranean Sea near Alexandria?

Nile water turns a thin ribbon of the eastern Sahara green. Egypt is almost entirely desert, so nearly all of its people live in the river's valley and delta.

Nearly all of the world's 1,750 or so cactus species are native to which part of the world?

The Americas are home to every wild cactus but one, a mistletoe cactus that also grows in tropical Africa and Sri Lanka. So no cactus is native to the Sahara or the Gobi.

Which desert arachnid glows a vivid blue-green when ultraviolet light is shone on it at night?

Scorpion shells contain fluorescent chemicals, so researchers counting them simply sweep the ground with a hand-held ultraviolet lamp.

Which German field marshal earned the nickname 'the Desert Fox' commanding tanks in North Africa?

Erwin Rommel was given the name by Allied and German reporters alike as his Afrika Korps raced back and forth across the Western Desert.

NASA tests life-detection gear in Chile's Atacama because its soil resembles that of which planet?

Mars has no closer stand-in on Earth: researchers who repeated the Viking landers' life-detection tests in the Atacama's driest soil found no sign of life at all.

Medieval camel caravans hauled slabs of salt across the Sahara chiefly to trade for which commodity?

Gold was plentiful south of the Sahara while salt was scarce, so in the market of Timbuktu the two were said to change hands almost weight for weight.

Salar de Uyuni, the world's largest salt flat and a breeding ground for flamingos, lies in which country?

Bolivia's great salt flat is so vast and so level that space agencies use it to calibrate their Earth-observing satellites.

Which small sociable mammal of the Kalahari Desert posts sentries to watch for danger while others forage?

Meerkat groups always keep a sentry on watch, and the animal is in fact a small mongoose, studied for decades by the Kalahari Meerkat Project.

Which ancient trade network split into northern and southern branches to skirt the deadly Taklamakan Desert?

Silk Road caravans kept to the Taklamakan's rim, stopping for relief at the thriving towns along its edges rather than risk the dunes in between.

Timbuktu, the fabled caravan city on the southern edge of the Sahara, lies in which modern country?

Mali's most storied city stands a short way north of the Niger River, and its libraries guard a famous hoard of medieval manuscripts.

The Tree of Ténéré, a lone acacia once called the most isolated tree on Earth, was destroyed in 1973 how?

Hit by a truck whose driver was reportedly drunk, the 300-year-old tree was moved to Niger's national museum, and a metal sculpture now marks its spot in the Sahara.

Which 1942 battle on Egypt's desert coast ended the Axis threat to the Suez Canal and the Middle East?

El Alamein gave the western Allies their first large success against the Axis since late 1941, and Churchill later wrote that before it they had never had a victory.

Which line of latitude crosses Mexico, the middle of the Sahara and the island of Taiwan?

The Tropic of Cancer has desert on or near it across the whole width of Africa, running through the heart of the Sahara from the Atlantic coast to Egypt.

Which narrow sea, an inlet of the Indian Ocean, lies between the Sahara and the deserts of Arabia?

The Red Sea has arid land on both shores and no river of any size flowing into it, which helps make it one of the saltiest seas in the world.

Which people, speakers of click languages, have hunted and gathered in the Kalahari for thousands of years?

San communities are counted among the oldest cultures on Earth: some genetic studies suggest their ancestors began to diverge from other human populations more than 100,000 years ago.

Which river fans out into a vast inland delta in the Kalahari Desert instead of ever reaching the sea?

Okavango floodwater spreads across northern Botswana every year, and nearly all of it evaporates or is taken up by plants, sustaining one of Africa's great wildlife refuges.

Which insects are blamed in one leading theory for the bare 'fairy circles' of southwest Africa's arid plains?

Termites are one of two main suspects. The rival theory says the grasses space themselves out as they compete with one another, and neither has been proven.

Which swarming insect of North Africa and Arabia can fly up to 150 km in a day and strip fields bare?

Locust swarms are staggeringly hungry: even a very small one, covering a single square kilometre, can eat as much food in a day as about 35,000 people.

Which desert bird soaks its belly feathers at a waterhole and flies the water back to its thirsty chicks?

Sandgrouse males have belly feathers built to hold water like a sponge, so they can ferry a drink to chicks that may be many miles from the nearest waterhole.

The Gobi, a desert of bare rock more than sand, stretches across the border of which two countries?

China and Mongolia share the Gobi, which ranks as the sixth-largest desert in the world and takes in open steppe as well as stony plains.

Since child jockeys were banned in the 2000s, racing camels in Qatar and the UAE have been ridden by what?

Small robots took over after the bans: Qatar's emir outlawed child riders in 2005 and ordered that every camel race be run with remote-controlled robotic jockeys by 2007.

Which Indian city, built of yellow sandstone around a hilltop fort, rises from the heart of the Thar Desert?

Jaisalmer's sandstone walls are pale yellow by day and deepen in colour at sunset, and its hilltop citadel, ringed by 99 bastions, is a World Heritage Site.

What were the courtyard inns built a day's journey apart for merchants crossing Persia and Central Asia?

Caravanserai walls enclosed an open courtyard ringed with stalls and chambers, so traders, their animals and their goods could all shelter safely for the night.

Which Syrian desert city, grown rich on caravan trade, rebelled against Rome under Queen Zenobia?

Palmyra paid dearly for Zenobia's revolt: the emperor Aurelian levelled the city in 273, and it was rebuilt only at a reduced size.

What name is given to the gently sloping tunnels that carry groundwater to farms in Iran's deserts?

Qanat tunnels, by most accounts developed in ancient Iran about 3,000 years ago, are reached by a line of well-like shafts; the same design is used from Afghanistan to North Africa under many local names.

Which triangular desert peninsula, home to Saint Catherine's Monastery, links two continents by land?

Sinai is the only part of Egypt that lies in Asia, and Saint Catherine's, built on the orders of the emperor Justinian, has been a working monastery for nearly 1,500 years.

Which nomadic Arab herders, known for black goat-hair tents, take their name from a word for desert-dweller?

Bedouin comes from the Arabic badawi, a term traditionally set against the word for settled people; the tribes historically herded camels, sheep and goats.

Which white desert antelope, extinct in the wild by the early 1970s, was bred in zoos and returned to Oman?

Oryx herds roam Arabia again thanks to that rescue, and in 2011 the species became the first ever moved from extinct in the wild back to merely vulnerable on the Red List.

Which British explorer's book Arabian Sands recounts his crossings of the Empty Quarter by camel and on foot?

Wilfred Thesiger crossed the great sand desert twice between 1945 and 1950, and his book became a classic record of a nomadic way of life that was already vanishing.

Coober Pedy, the outback town where residents escape the heat in hillside dugouts, mines which gemstone?

Opal has been dug at Coober Pedy since 1915, earning the town the title of opal capital of the world; its cave homes stay at a constant temperature while the surface bakes.

Kata Tjuta, a cluster of 36 red rock domes near Uluru, was long known by which English name?

The Olgas took that name from the tallest dome, Mount Olga, which an explorer named in 1872 for Queen Olga of Württemberg; it stands almost 200 m higher than Uluru.

Which Australian outback town stages the Henley-on-Todd Regatta, a 'boat' race run along a dry, sandy river?

Alice Springs called the regatta off in 1993 for the unlikeliest of reasons: there was water in the Todd River.

Which long-eared marsupial of Australia's deserts is sold in chocolate form as a rival to the Easter Bunny?

Bilby chocolates double as a conservation campaign: one Adelaide chocolatier made 950,000 of them between 1993 and 2020 and gave the proceeds to environmental work.

Which usually dry salt basin of the Australian outback holds the continent's lowest natural point?

Lake Eyre is most often empty and has filled completely only a handful of times since 1860; when it does, it becomes the largest lake in Australia.

The Nullarbor Plain, home to the world's longest straight railway, has a Latin name meaning what?

No trees is the literal sense of the Latin nullus arbor, and it fits: the plain is a flat, almost treeless sweep of arid country along Australia's southern coast.

Which cold ocean current, flowing north along Chile and Peru, is largely to blame for the Atacama's aridity?

The Humboldt Current starves the coast of rain but feeds the sea: its cold, upwelled waters yield almost a fifth of the world's marine fish catch.

Which climate pattern brings the rare rains that make Chile's Atacama Desert burst into a carpet of flowers?

El Niño warms the ocean off Chile's Pacific coast, lifting evaporation and rainfall; dormant seeds and bulbs then germinate, and more than 200 flower species bloom in the same spring.

Chuquicamata, a pit 850 metres deep in Chile's Atacama, is one of the world's great mines of which metal?

Copper from Chuquicamata made it Chile's most productive mine for most of the 20th century, and by excavated volume it is the largest open pit of its kind in the world.

Which hard, chemically inert mineral is the most common ingredient of sand in the world's inland deserts?

Quartz outlasts its neighbours: when granite weathers, the feldspar in it breaks down faster, leaving the tough silica grains behind to be blown into dunes.

Fulgurites, the hollow glass tubes sometimes found in desert sand, are created when what strikes the ground?

Lightning fuses the grains in an instant, since the channel of a bolt is hotter than 30,000 kelvin; the name comes from fulgur, the Latin word for it.

Which atmospheric cell, rising at the equator and sinking near latitude 30, creates the subtropical deserts?

Hadley cells wring the rain out of rising air near the equator, then drop the dried air in the subtropics, where it suppresses rainfall over many of Earth's deserts.

Which type of dune piles up into a pyramid with three or more arms where winds blow from several directions?

Star dunes grow upward rather than sideways, which makes them giants: those of the Badain Jaran Desert stand up to 500 metres tall.

What do geologists call a stone pitted, grooved or polished into flat faces by wind-driven sand?

Ventifact grooves run parallel to the wind that cut them, so undisturbed ancient examples show geologists which way the wind once blew.

Which hopping rodent of Asian and North African deserts moves on two long hind legs like a miniature kangaroo?

Jerboa escapes are spectacular: an animal that normally hops about 10 centimetres can leap up to 3 metres when a predator closes in, turning sharply to throw it off.

Frank Herbert was inspired to write Dune after visiting shifting coastal sand dunes in which US state?

Oregon's dunes near the town of Florence were being pinned down with planted grasses in 1957, and Herbert's research for an article on the scheme sparked his interest in deserts and ecology.

Which fruit crop of the Sahara and Middle East has separate male and female plants and is pollinated by hand?

Dates grow only on female palms, and with a grower's help a single male palm can pollinate up to 100 of them, so most of the males are simply pruned out.

Brine beneath the salt flats of the high Andes is one of the richest stores of which battery metal?

Lithium is so concentrated in these Andean salt pans that the border region is nicknamed the Lithium Triangle, and one Chilean flat holds the richest brine known anywhere.

Which hot wind carries Saharan dust across the Mediterranean, sometimes falling on Italy as 'blood rain'?

Sirocco air starts out dry over the Sahara, picks up moisture as it crosses the sea and can reach hurricane speeds; the red colour in the rain is desert dust.

Which cold ocean current wraps southwest Africa's shipwreck-strewn Skeleton Coast in fog for much of the year?

Benguela water wells up cold from the Atlantic depths and chills the sea air into fog; the whale and seal bones that once littered its beaches gave the coast its name.