Instruct: Given a question, retrieve documents that can help answer the question.
Query: How large is the Sahara desert?
The Sahara is a vast desert of northern Africa, measuring about 932 miles from north to south and 2484 miles from east to west, and dotted with oases which are centres of population. Eight years after the journey of the French explorer Henri Duveyrier (1859–61), which had important scientific results, Pope Pius IX on 6 August 1868 appointed the Archbishop of Algiers, Mgr Charles Lavigerie, delegate Apostolic of the Sahara and the Sudan. In the same year the Jesuits established themselves at Laghouat, the extremity occupied by French arms. In 1871 they sent to Mgr Lavigerie a long report in which they advocated the establishment of dispensaries and schools. In 1872 Father Charmetant and two other White Fathers (Missionary Fathers of Africa of Algiers) replaced the Jesuits at Laghouat. In 1873 the White Fathers established themselves at Biskra, Ouargla, Touggart and Gerryville. Later a station was founded at Melili in M'zab.
Two successive attempts were made by the White Fathers to reach the Sudan region by crossing the Sahara, thus reaching Timbuktu, a large market for black slaves, there to join in the struggle against slavery. The first attempt was made in December, 1878, by Fathers Menoret, Paulmier and Bouchand; they were slain in April, 1876 by their Touarag guides, being the first martyrs of the Society of White Fathers, and the cause of their beatification was introduced at Rome in 1909. After this disaster the White Fathers founded two stations, not farther north in the desert, but to the north-east, at Tripoli and Ghadames, both in Libya. The massacre of the explorer Flatters and his companions (1880–81) did not discourage the White Fathers in their second attempt to cross the Sahara. In 1881 Father Richard set out from Ghadames, having become so Arabian in speech and bearing that no one suspected his nationality. He intended to establish himself with Fathers Morat and Pouplard at Ghat in the midst of the Libyan desert, but all three were assassinated.
The wide and endorheic Caspian Sea has a north–south orientation and its main freshwater inflow, the Volga River, enters at the shallow north end. Two deep basins occupy its central and southern areas. These facts lead to horizontal differences in temperature, salinity, and ecology. The Caspian Sea spreads out over nearly 750 miles (1,200 km) from north to south, with an average width of 200 miles (320 km). It covers a region of around 149,200 square miles (386,400 square km)—bigger than the region of Japan—and its surface is about 90 feet (27 meters) below sea level. The sea bed in the southern part reaches as low as 1,023 m (3,356 ft) below sea level, which is the second lowest natural depression on earth after Lake Baikal (−1,180 m, −3,871 ft). The ancient inhabitants of its coast perceived the Caspian Sea as an ocean, probably because of its saltiness and large size.
There are many varieties of Arabic (also called dialects of Arabic or vernacular languages) in existence. Arabic is a Semitic language within the Afroasiatic family that originated on the Arabian Peninsula. It is classified as a macrolanguage comprising 30 modern varieties, including its standard form. The largest divisions occur between the spoken languages of different regions. Some varieties of Arabic in North Africa, for example, are not easily comprehensible to an Arabic speaker from the Levant or the Persian Gulf. Within these broad regions further and considerable geographic distinctions exist, within countries, across country borders, even between cities and villages.
The Scottsdale Arabian Horse Show is the world's largest Arabian horse show, held annually in Scottsdale, Arizona. Beginning in 1955, the show has grown from 50 horses and a dozen trainers/owners to more than 2200 horses and over 1300 owners. Called the "Super Bowl of the Arabian World", it represents the first leg in the Arabian Triple Crown, the other two major competitions being the Canadian and U.S. National Arabian Championships. In addition to the competition, the show acts as a fundraiser for the Arabian Horse Association of Arizona, which has donated millions of dollars to charity from the proceeds of the show.
Asia is the largest continent on Earth. It covers 9% of the Earth's total surface area (or 30% of its land area), and has the largest coastline, at . Asia is generally defined as comprising the eastern four-fifths of Eurasia. It is located to the east of the Suez Canal and the Ural Mountains, and south of the Caucasus Mountains (or the Kuma–Manych Depression) and the Caspian and Black Seas. It is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean and on the north by the Arctic Ocean. Asia is subdivided into 48 countries, three of them (Russia, Kazakhstan and Turkey) having part of their land in Europe.
The Caspian Depression is below sea-level, consisting of large areas of marshlands in the eastern region. It is one of the largest flat lowland areas in Central Asia, covering approximately . The area is very rich in underground oil and gas reserves, and oil and natural gas pipelines cross the depression from north to south and east to west. Many geologists believe the Caspian Sea and the depression were formed by tectonic forces. Some of them also believe that the North Caspian depression became separated from the open ocean in ancient times to form an enormous salt lake. Part of the ancient Silk Road ran through this region. The two largest cities in the depression are Astrakhan in Russia, and Atyrau in Kazakhstan. Today, the region is used mainly for livestock raising.
Antarctica ( or , ) is Earth's southernmost continent. It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean. At , it is the fifth-largest continent. For comparison, Antarctica is nearly twice the size of Australia. About 98% of Antarctica is covered by ice that averages in thickness, which extends to all but the northernmost reaches of the Antarctic Peninsula.
The African bush elephant is the largest and heaviest land animal on Earth, being up to tall at the shoulder and in weight (a male shot in 1974, near Mucusso, southern Angola). On average, males are about tall at the shoulder and in weight, while females are much smaller at about tall at the shoulder and in weight. Elephants attain their maximum stature when they complete the fusion of long-bone epiphyses, occurring in males around the age of 40 and females around the age of 25. Their large size means that they must consume around 50 gallons of water every day in order to stay hydrated.
The sea has a surface area of 371,000 km (143,200 sq mi) (not including the detached lagoon of Garabogazköl) and a volume of 78,200 km(18,800 cu mi). It has a salinity of approximately 1.2% (12 g/l), about a third of the salinity of most seawater.
It is claimed by some Arab authors that the dialect of Belad Ghamid and Zahran (Now known as Al Baha province in Saudi Arabia) is nearest to classical Arabic. Ahmed Abdul Ghafur Attar (Arabic : احمد عبدالغفور عطار ) has said in an article* that the language of the Hejaz (Arabic لهجات الحجاز), especially that which is spoken in Belad Ghamdi and Zahran is close to the Classical Language.
South Sudan – landlocked country in east-central Africa that is part of the United Nations subregion of Eastern Africa. It previously known as Southern Sudan. It is located south of Sudan, and includes the vast swamp region of the Sudd, formed by the White Nile and known locally as the "Bahr al Jabal". South Sudan became an independent state on 9 July 2011, following a referendum that passed with 98.83% of the vote. It is a United Nations member state, a member state of the African Union, and a member state of the Intergovernmental Authority on Development. In July 2012, South Sudan signed the Geneva Conventions. Its current capital is Juba, which is also its largest city. The capital city is planned to be changed to the more centrally located Ramciel in the future.Geography of South SudanEnvironment of South Sudan
With a surface area of approximately , Lake Victoria is Africa's largest lake by area, the world's largest tropical lake, and the world's second largest fresh water lake by surface area after Lake Superior in North America. In terms of volume, Lake Victoria is the world's ninth largest continental lake, containing about of water.
The coast is for the most part flat, with occasional low cliffs and bluffs of red sandstone. There is but one deep inlet of the sea – Great Fish Bay (or Baía dos Tigres). Farther north are Port Alexander, Little Fish Bay and Lobito Bay, while shallower bays are numerous. Lobito Bay has water sufficient to allow large ships to unload close inshore. The coastal lowland rises from the sea in a series of low terraces. This region varies in width from about 25 km near Benguela to more than 150 km in the Cuanza River Valley just south of Angola's capital, Luanda, and is markedly different from Angola's highland mass. The Atlantic Ocean's cold, northwardflowing Benguela Current substantially reduces precipitation along the coast, making the region relatively arid or nearly so shaouth of Benguela (where it forms the northern extension of the Namib Desert), and quite dry even in its northern reaches. Even where, as around Luanda, the average annual rainfall may be as much as fifty centimeters, it is not common for the rains to fail. Given this pattern of precipitation, the far south is marked by sand dunes, which give way to dry scrub along the middle coast. Portions of the northern coastal plain are covered by thick brush.
Due to scarcity of water, the Namib Desert Horse sometimes goes without water for as long as thirty hours in summer and has been known to go close to 72 hours without water during the winter, significantly longer than most horses, even other feral herds. A 1991 study suggested that in 75 years of genetic isolation and water scarcity the population had developed physiological mechanisms which improved their ability to conserve water. In 1993, a second study showed that the physiological water-conservation ability did not differ between Namib Desert Horses and other populations when dehydrated for periods of up to 60 hours, but suggested that the Namib Desert Horse would show improved conservation ability when dehydration periods were extended to upwards of 72 hours, a common occurrence in their feral state.
Khartoum State () is one of the eighteen states of Sudan. Although it is the smallest state by area (22,142 km), it is the most populous (5,274,321 in 2008 census). It contains the country's second largest city by population, Omdurman, and the city of Khartoum, which is the capital of the state as well as the national capital of Sudan. The capital city contains offices of the state, governmental and non-governmental organizations, cultural institutions, and the main airport.
Lake Victoria is the largest lake in Africa and the second largest fresh-water lake in the world. Many water sports are available there. Lakeside leisure sites are also available.
Yellowstone National Park spans an area of , comprising lakes, canyons, rivers and mountain ranges. Yellowstone Lake is one of the largest high-elevation lakes in North America and is centered over the Yellowstone Caldera, the largest supervolcano on the continent. The caldera is considered an active volcano. It has erupted with tremendous force several times in the last two million years. Half of the world's geysers and hydrothermal features are in Yellowstone, fueled by this ongoing volcanism. Lava flows and rocks from volcanic eruptions cover most of the land area of Yellowstone. The park is the centerpiece of the Greater Yellowstone Ecosystem, the largest remaining nearly-intact ecosystem in the Earth's northern temperate zone. In 1978, Yellowstone was named a UNESCO World Heritage Site.
Sanaʽa is one of the oldest continuously inhabited cities in the world. At an elevation of , it is also one of the highest capital cities in the world, and is next to the Sarawat Mountains of Jabal An-Nabi Shu'ayb and Jabal Tiyal, considered to be the highest mountains in the country and amongst the highest in the region. Sanaʽa has a population of approximately 3,937,500 (2012), making it Yemen's largest city.
The Blue Hole is a diving location on the southeast Sinai, a few kilometres north of Dahab, Egypt on the coast of the Red Sea.
Further northwest is Lake Victoria on the Kenya–Uganda–Tanzania border. This is the largest lake in Africa by surface area and is traditionally named as the source of the Nile River. Southwest of this, separating Tanzania from the Democratic Republic of the Congo, is Lake Tanganyika. This lake is estimated to be the second deepest lake in the world after Lake Baikal in Siberia. The western portion of the country between Lakes Victoria, Tanganyika, and Malawi consists of flat land that has been categorised by the World Wildlife Fund as part of the Central Zambezian Miombo woodlands ecoregion. Just upstream from the Kalambo Falls, there is one of the most important archaeological sites in Africa.
Shiraz (; , "Šīrāz", ) is the fifth-most-populous city of Iran and the capital of Fars Province (Old Persian as Pars). At the 2016 census, the population of the city was 1,869,001 and its built-up area with "Shahr-e Jadid-e Sadra" (Sadra New Town) was home to 1,565,572 inhabitants. Shiraz is located in the southwest of Iran on the "Rudkhaneye Khoshk" (The Dry River) seasonal river. It has a moderate climate and has been a regional trade center for over a thousand years. Shiraz is one of the oldest cities of ancient Persia.
The surface of the desert ranges from large areas of sand dunes (erg), to stone plateaus (hamadas), gravel plains (reg), dry valleys (wadis), and salt flats. The only permanent river that crosses the ecoregion is the Nile River, which originates in central Africa and empties northwards into the Mediterranean Sea. Some areas encompass vast underground aquifers resulting in oases, while other regions severely lack water reserves.
The Sahara Desert features a hot desert climate (Köppen climate classification "BWh"). The Sahara Desert is one of the driest and hottest regions of the world, with a mean temperature sometimes over and the average high temperatures in summer are over for months at a time, and can even soar to . In desert rocky mountains such as the Tibesti in Libya or the Hoggar in Algeria, average highs in summer are slightly moderated by the high elevation and are between at elevation. Daily variations may also be extreme: a swing from has been observed. Typical temperature swings are between .
The Sahara Desert ecoregion, as defined by the World Wide Fund for Nature (WWF), includes the hyper-arid center of the Sahara, between 18° and 30° N. It is one of several desert and xeric shrubland ecoregions that cover the northern portion of the African continent.
The Kiffian culture is a prehistoric industry, or domain, that existed between 10,000 and 8,000 years ago in the Sahara, during the Neolithic Subpluvial. Human remains from this culture were found in 2000 at a site known as Gobero, located in Niger in the Ténéré Desert. The site is known as the largest and earliest grave of Stone Age people in the Sahara desert. The Kiffians were skilled hunters. Bones of many large savannah animals that were discovered in the same area suggest that they lived on the shores of a lake that was present during the Holocene Wet Phase, a period when the Sahara was verdant and wet. The Kiffian people were tall, standing over six feet in height. Craniometric analysis indicates that this early Holocene population was closely related to the Late Pleistocene Iberomaurusians and early Holocene Capsians of the Maghreb, as well as mid-Holocene Mechta groups. Traces of the Kiffian culture do not exist after 8,000 years ago, as the Sahara went through a dry period for the next thousand years. After this time, the Tenerian culture colonized the area.
The Sahara Desert was chosen as an ideal location for solar farms as it is exposed to bright sunshine nearly all the time, roughly between 80% and 97% of the daylight hours in the best cases. This is the sunniest year-round area on the planet. In the world's largest hot desert, there is an extremely vast area, covering almost the whole desert, that receives more than 3,600 h of yearly sunshine. There is also a very large area in excess of 4,000 h of sunshine annually. The highest solar radiation received on the planet is in the Sahara Desert, under the Tropic of Cancer. This results from a general, strong lack of cloud cover year-round and a geographical position under the tropics.