Пустеля Сахара (of Arab “desert”) – one of the most legendary and ruthless land in the world, which carries the sense of time and forces of nature, old, legends, wonders and mysteries. Пустеля Сахара відігравала одну з найбільш ключових глав в західній історії.
Location
Pokryvayayuchy most of the northern third of the African continent, or so 3,5 million square miles, Sahara Desert extends east from the Atlantic Ocean close to 3000 miles to the Nile and the Red Sea, and south of the Atlas Mountains of Morocco and UM coast more than 1000 miles to the so-called Sahel savanna. More than 16 times exceeds the Sahara Desert France, and part of it occupied almost all Mauritania, Western Sahara, Algeria, Libya, Egypt and Niger; and even the southern half of Tunisia and northern Mali, Chad and Sudan
Landscape
Topographical features of the Sahara desert include not only religious fields of sand – dunes, but barren mountains, plateau, sands, covered with gravel plains, small pools and large oases. It is the highest point in Chad – Mount-Snapshot (an extinct volcanic crater, which rises to 11,204 feet above sea level at the peak), and the lowest point in Egypt – Letters to the (anhydrous oasis, which is on 436 feet below sea level on the spot cavity).
Legendary dunes in Sahara desert area, which cover only about 15 percent of the entire surface of the desert, located mainly in the north central region, in Algeria and Libya. Most sand dunes - sand invasion, що завдяки вітровій силі та під дією сили тяжіння, becomes a natural wonder, sculpture resembling a mountain. Dunes are the windward side or reverse slope(backslope) and the leeward side or sliding surface(slipface). The prevailing winds blow up the sand up backslope, until it reaches the crest, and then collapses under gravity, cascading down slipface. Wind can retain corrugated surface on its way.
More information about the desert,natural phenomenon, on scientific news, you can find at Science News.
Dune Sahara Desert visible from the eastern tip of Morocco.
Dune acquire diverse and complex forms. Some examples:
Climbing the dunes, having hands or “horns”, placed in the wind. These dunes are formed by winds, that blow from the same direction for a long period.
Linear dunes, with many, straight or slightly wavy shape, can extend for several miles. They are formed by winds, that blow from any of the two directions.
Transverse dunes, which sharply crested, Chablais are rough-shaped form, and are parallel, can reach nearly a thousand feet high and stretch over a hundred miles long. They are formed in line with the prevailing wind, which changed direction for a long period and redistributed sand dunes earlier.
Зоряні дюни мають центральні пірамідальні насипи з трьома або більше вихідними рукавами, each javljaetsja backslope and slipface. Star Sahara desert dunes formed by winds, that blow from several directions.
Dome dunes are oval shaped mound, what, oddly enough, have backslope or slipface. Relatively rare, вони мають тенденцію формуватися проти вітру у крайніх частинах дюни. Дюни пустелі Сахари з їх різними формами викликають багато запитань про динаміку їх утворення.
A source: http://619.com.ua/
