| Tibesti | |
| Range | |
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The Tibesti, including Emi Koussi summit, seen from the International Space Station
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| Countries | Chad, Libya |
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| Highest point | Emi Koussi |
| - elevation | 3,445 m (11,302 ft) |
| - coordinates | |
The Tibesti Mountains are a range of inactive volcanoes located on the northern edge of the Chad Basin in the Borkou- and Tibesti Region of northern Chad. The massif is one of the most prominent features of the Central-Sahara desert and covers an area of approximately 100,000 km². The northern slopes extend into southern Libya. It is one of the isolated Areas on Earth and the people called the Tibesti as mountains of hunger, it can only feed a few people. The biggest city is Bardaï, with only 1.500 residents. The region is a settlement area of the Tubu people and in drought periods in the lowlands visit the nomadic Tuareg this area.
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The mountains are the largest and highest range in the Central Sahara, formed by a volcanic group. Most are inactive volcanoes, but the Smithsonian Institution lists four potentially active volcanos. The toponymy of the Tibesti massif is derived from the Arabic and Teda-daza languages of the Toubou people and is used throughout the region. The term ehi refers to peaks, rocky hills, emi to larger mountains or mountainous regions; ehra to calderas. The term Tarso designates a high plateau or gently-sloping mountainsides; for example the Ehi Mosgau is a 3,100 meter high Stratovolcano with a small summit area, near Tarso Voon. The Ehra Kohor is a caldera on the Emi Koussi summit.
The highest peak in the mountains is Emi Koussi, 3,415 m. Other summits include Kegueur Terbi (3,376 m), Tarso Taro (3,325 m), the potentially active volcano Tarso Tousside (3,265 m) and Tarso Voon (3,100 m).[1] The peak Bikku Bitti, located in northern area, is the highest mountain in Libya. While the high peaks themselves are all constituted of volcanic material, the mountains stand on broad uplifted area caused by a mantle plume. The intense activity of the volcanism began as early as the Oligocene, though the major products that mark its surface date from Lower Miocene to the Quaternary period. It shows as a key example of continental hot spot volcanism. In several areas of mountains are hot springs and solfataras, most pronounced geothermal features are in Soborom solfatara field on the north-western flank of Tarso Voon volcano.[2]
The basement of the mountains is Precambrian Schist, overlaid with Paleozoic Sandstone, all capped by Tertiary and Pleistocene outpourings of basalt.
The range has a substantially wetter climate than the arid surrounding desert. The run-off of precipitation in the mountains is more regular than the lowland desert. The rainfall during the 1950's was considerable, although still probably under 600 mm/m² per year. Recently, rainfall has been less than 60 mm/m² per year in new century(2000). Lowland wadi areas called Enneri, receive their water from the mountains down storm channels. The rainfall differs massively from year to year; for example the biggest Enneri, Bardargué, flowed at a rate of 425 m³/sec in 1954, but in the subsequent 9 years, was entirely dry for 4 years, had one short flow each year for 4 years (peaking at 5 m³/sec), and in the ninth year had three flows peaking at 4, 9 and 32 m³/sec.
The mean maximum temperature is approximately 30°C in the lowlands and falls to 20°C in the highest elevations. Mean minimum temperatures are 12°C in the lowlands, but fall to 9°C over most of the ecoregion and are as low as 0°C at the highest elevations during winter months.
Due to the aridity of the Sahara, the Tibesti massif is nearly free of accumulated vegetal soil, and robust plant life is deficient in almost every area throughout the year. The Tibesti Mountains lies in the ecological region, they called Tibesti-Djebel Uweinat Montane Xeric Woodlands. In these mountains, there is only one lake, the Mare de Zoui, along with a number of oases.
The Tibesti mountain vegetation varies according to elevation and slope. Large Enneri areas radiate from the southwestern slopes supporting tree species such as the Doum Palm (Hyphaene thebaica), Salvadora persica, Tamarix articulata, and Acacia albida, and other tropical herbs in the genera Abutilon, Hibiscus, and Tephrosia. The Saharamontane vegetation of the higher elevations supports the endemic Ficus teloukat, which grows on the south and southwestern slopes, Myrtus nivellei on the western slopes, and Tamarix gallica nilotica on the wetter northern slopes. Remnant tropical and Mediterranean plant species are seen throughout this ecoregion, including palms,Hibiscus sp. and Rhynchosia sp.
The ecoregion supports populations of several important Saharan large mammals including the Dorcas Gazelle (Gazella dorcas), Barbary Sheep (Ammotragus lervia) and Cheetah (Acinonyx jubatus). Small mammals and their predators are also abundant, including Hyrax (Procavia capensis), Brown Hare (Lepus capensis) and Spiny Mouse (Acomys spp.). The reptile and amphibian fauna is poor in this area.
There are a number of vegetative and wildlife species in the Tibesti Mountains. In Chad there may be as many as 50 endangered Painted Hunting Dogs, but some regard these relict populations in the Tibesti Mountains as extirpated, partially from Darfur refugee turmoil and other Sudan generated conflict.[3]
The mountains are known for their ancient cave paintings, mostly dating from the 5th to the 3rd millennium BC, and for the geysers and hot springs in the Soboroum solfataric field, where waters issue from the ground with temperatures between 22 and 88°C. The Yi Yerra warm springs (37°C) are located on the southern flank of Emi Koussi at an altitude of 850 m above sea level. The local populations use the hot and warm springs for medical purposes.
The area has long been home to the Toubou people which had trading relations with Carthage from the 500s BC. The main town in the area is Bardaï, while Zouar and Aouzou are smaller settlements.
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