The Sahara Desert is the world's largest hot desert; it stretches over 3,, The Great Victoria Desert stretches across , square miles in both South. Warplanes roared overhead, tanks rumbled across the desert and smoke Press Agency described as one of the world's biggest military exercises. . PG&E's ,volt Caribou Palermo line date to December , when. The boundaries of the Sahara are the Atlantic Ocean on the west, the Atlas limit of the Sahara corresponds to the northern limit of Date Palm cultivation.
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The Virgin Mary munched on dates when she was pregnant. It uses four times as much water as wheat. In , based of DNA studies, scientists concluded that corn did in fact evolve from teosinte. Japanese scientist are investigating properties of watermelon as an ingredient for cosmetics and health drinks.
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'Thunder' in Saudi desert as major military drill ends
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The Saudi-Franco partnership is in part aimed at preserving the site from further erosion and vandalism it has faced.
At one archeological site called Al-Khoraiba, Anazi pointed at a bereft cistern. Photos taken by French explorers Jaussen and Savignac, who visited the area in the early 20th century, showed the same cistern once featured the statue of a deity. The walled city of Al-Ula, with tightly packed mud-brick and stone houses that were inhabited until modern times, sits decaying under the scorching sun. But before a preservation plan is launched in collaboration with France, all archaeological treasures need to be accounted for, said Amr al-Madani, head of the Royal Al-Ula Commission.
A massive two-year surveying programme began in March, which includes scanning via helicopters, satellites, drones and a remote sensing technology called Lidar, he told AFP. A Franco-Saudi deal to develop Al-Ula calls for the creation of a dedicated agency modelled on the lines of the French museums agency, which spearheaded the establishment of the Louvre museum in Abu Dhabi.
At least one large museum is planned to be built in Al-Ula. Al-Ula is expected to fully open up to global tourists within three to five years, launching the site as what Saudi officials describe as "a gift to the world". Archaeologists last year used Google Maps to find hundreds of stone "gates" built from rock in a remote Saudi desert, which may date back as far as 7, years. Fossils of dinosaurs, including Afrovenator, Jobaria and Ouranosaurus, have also been found here.
The modern Sahara, though, is not as lush in vegetation, except in the Nile Valley, at a few oases, and in the northern highlands, where Mediterranean plants such as the olive tree are found to grow.
The region has been this way since about BC. It has been reported that the Sahara is expanding south by as much as 30 miles per year, overwhelming degraded grasslands,  taking over the Sahel, the dry tropical savanna that has defined the Sahara's southern limit. Global warming and poor farming methods have been given as possible causes.
This spreading of deserts is known as "desertification," and the phenomenon is occurring in other desert areas worldwide.
It is one of three distinct physiographic provinces of the African massive physiographic division. The desert landforms of the Sahara are shaped by wind eolian or by occasional rains, and include sand dunes and dune fields or sand seas erg , stone plateaus hamada , gravel plains reg , dry valleys wadi , and salt flats shatt or chott. The highest peak in the Sahara is Emi Koussi, a shield volcano in the Tibesti range of northern Chad.
Most of the rivers and streams in the Sahara are seasonal or intermittent, the chief exception being the Nile River, which crosses the desert from its origins in central Africa to empty into the Mediterranean. The center of the Sahara is hyper-arid, with little vegetation. The northern and southern reaches of the desert, along with the highlands, have areas of sparse grassland and desert shrub, with trees and taller shrubs in wadis where moisture collects.
To the north, the Sahara reaches to the Mediterranean Sea in Egypt and portions of Libya, but in Cyrenaica and the Magreb, the Sahara borders Mediterranean forest, woodland, and shrub ecoregions of northern Africa, which have a Mediterranean climate characterized by a winter rainy season. According to the botanical criteria of Frank White and geographer Robert Capot-Rey, the northern limit of the Sahara corresponds to the northern limit of Date Palm cultivation Phoenix dactylifera , and the southern limit of Esparto Stipa tenacissima , a grass typical of the Mediterranean climate portion of the Maghreb and Iberia.
The northern limit also corresponds to the mm isohyet of annual precipitation. The southern limit of the Sahara is indicated botanically by the southern limit of Cornulaca monacantha a Chenopodiaceae , or northern limit of the Cenchrus biflorus, a grass typical of the Sahel.
However, not long after the end of the ice sheets, the monsoon, which currently brings rain only as far as the Sahel, came further north and counteracted the drying trend in the southern Sahara.
The monsoon in Africa and elsewhere is due to heating during the summer. Air over land becomes warmer and rises, pulling in cool wet air from the ocean, which causes rain. Paradoxically, the Sahara was wetter when it received more solar insolation in the summer.