The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez (leading to the Suez Canal). The Red Sea is a Global 200 ecoregion. The sea is underlain by the Red Sea Rift which is part of the Great Rift Valley.
The Red Sea has a surface area of roughly 438,000 km² (169,100 mi²). It is about 2250 km (1398 mi) long and, at its widest point, 355 km (220.6 mi) wide. It has a maximum depth of 2211 m (7254 ft) in the central median trench, and an average depth of 490 m (1,608 ft). However, there are also extensive shallow shelves, noted for their marine life and corals. The sea is the habitat of over 1,000 invertebrate species, and 200 soft and hard corals. It is the world's northernmost tropical sea.
The Red Sea lies between arid land, desert and semi-desert. The main reasons for the better development of reef systems along the Red Sea is because of its greater depths and an efficient water circulation pattern, The Red Sea water mass exchanges its water with the Arabian Sea, Indian Ocean via the Gulf of Aden. These physical factors reduce the effect of high salinity caused by evaporation water in the north and relatively hot water in the south.
The climate of the Red Sea is the result of two distinct monsoon seasons; a northeasterly monsoon and a southwesterly monsoon. Monsoon winds occur because of the differential heating between the land surface and sea. Very high surface temperatures coupled with high salinities makes this one of the hottest and saltiest bodies of seawater in the world.
The average surface water temperature of the Red Sea during the summer is about 26 °C (79 °F) in the north and 30 °C (86 °F) in the south, with only about 2 °C (3.6 °F) variation during the winter months. The overall average water temperature is 22 °C (72 °F). Today surface water temperatures remain relatively constant at 21–25 °C (70–77 °F). Temperature and visibility remain good to around 200 m (656 ft). The sea is known for its strong winds and unpredictable local currents.
Wind regime :
With the exception of the northern part of the Red Sea, which is dominated by persistent north-west winds, with speeds ranging between 7 km/h (4.3 mph) and 12 km/h (7.5 mph), the rest of the Red Sea and the Gulf of Aden are subjected to the influence of regular and seasonally reversible winds. The wind regime is characterized by both seasonal and regional variations in speed and direction with average speed generally increasing northward.
Wind is the driving force in the Red Sea for transporting the material either as suspension or as bedload. Wind induced currents play an important role in the Red Sea in initiating the process of resuspension of bottom sediments and transfer of materials from sites of dumping to sites of burial in quiescent environment of deposition. Wind generated current measurement is therefore important in order to determine the sediment dispersal pattern and its role in the erosion and accretion of the coastal rock exposure and the submerged coral beds.
The Red Sea was formed by Arabia splitting from Africa due to movement of the Red Sea Rift. This split started in the Eocene and accelerated during the Oligocene. The sea is still widening and it is considered that the sea will become an ocean in time (as proposed in the model of John Tuzo Wilson). In 1949, a deep water survey reported anomalously hot brines in the central portion of the Red Sea. Later work in the 1960s confirmed the presence of hot, 60 °C (140 °F), saline brines and associated metalliferous muds. The hot solutions were emanating from an active subseafloor rift. The highly saline character of the waters was not hospitable to living organisms.
Living resources :
The Red Sea is a rich and diverse ecosystem. More than 1200 species of fish have been recorded in the Red Sea, and around 10% of these are found nowhere else. This also includes 42 species of deepwater fish.
The rich diversity is in part due to the 2,000 km (1,240 mi) of coral reef extending along its coastline; these fringing reefs are 5000–7000 years old and are largely formed of stony acropora and porites corals. The reefs form platforms and sometimes lagoons along the coast and occasional other features such as cylinders (such as the Blue Hole (Red Sea) at Dahab). These coastal reefs are also visited by pelagic species of red sea fish, including some of the 44 species of shark.
The Red Sea also contains many offshore reefs including several true atolls. Many of the unusual offshore reef formations defy classic (i.e., Darwinian) coral reef classification schemes, and are generally attributed to the high levels of tectonic activity that characterize the area.
The special biodiversity of the area is recognized by the Egyptian government, who set up the Ras Mohammed National Park in 1983. The rules and regulations governing this area protect local marine life, which has become a major draw for diving enthusiasts.
The sea is known for its spectacular recreational diving sites, such as Ras Mohammed, SS Thistlegorm (shipwreck), Elphinstone, The Brothers, Dolphin Reef and Rocky Island in Egypt and less known sites in Sudan such as Sanganeb, Abington, Angarosh and Shaab Rumi.
The Red Sea became a sought-after diving destination after the expeditions of Hans Hass in the 1950s, and later by Jacques-Yves Cousteau. Popular tourist resorts include El Gouna, Hurghada, Safaga, Marsa Alam, on the western shore of the Red Sea, and Sharm-El-Sheikh, Dahab, and Taba on the Egyptian side of Sinaï, as well as Aqaba in Jordan and Eilat in Israel in an area known as the Red Sea Riviera.
The popular tourist beach of Sharm el-Sheikh was closed to all swimming in December 2010 due to several serious shark attacks, including one fatality. As of December 2010, scientists are investigating the attacks and have identified, but not verified, several possible causes including over-fishing which causes large sharks to hunt closer to shore, tourist boat operators who chum offshore for shark-photo opportunities, and reports of ships throwing dead livestock overboard. The sea's narrow width, significant depth, and sharp drop-offs, all combine to form a geography where large deep-water sharks can roam in hundreds of meters of water, yet be within a hundred meters of swimming areas.