A summit is a point on a surface, higher in elevation than all points adjacent to it. The topographic terms acme, apex and zenith are synonymous; the term top is used only for a mountain peak, located at some distance from the nearest point of higher elevation. For example, a big massive rock next to the main summit of a mountain is not considered a summit. Summits near a higher peak, with some prominence or isolation, but not reaching a certain cutoff value for the quantities, are considered subsummits of the higher peak, are considered part of the same mountain. A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top. Summit may refer to the highest point along a line, trail, or route; the highest summit in the world is Everest with height of 8844.43 m above sea level. The first official ascent was made by Sir Edmund Hillary, they reached the mountain`s peak in 1953. Whether a highest point is classified as a summit, a sub peak or a separate mountain is subjective; the UIAA definition of a peak is.
Otherwise, it's a subpeak. In many parts of the western United States, the term summit refers to the highest point along a road, highway, or railroad. For example, the highest point along Interstate 80 in California is referred to as Donner Summit and the highest point on Interstate 5 is Siskiyou Mountain Summit. A summit climbing differs from the common mountaineering. Summit expedition requires: 1+ year of training, a good physical shape, a special gear. Although a huge part of climber’s stuff can be left and taken at the base camps or given to porters, there is a long list of personal equipment. In addition to common mountaineers’ gear, Summit climbers need to take Diamox and bottles of oxygen. There are special requirements for crampons, ice axe, rappel device, etc. Geoid Hill – Landform that extends above the surrounding terrain Nadir Summit accordance Peak finder Summit Climbing Gear List
An endorheic basin is a limited drainage basin that retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation. Such a basin may be referred to as a closed or terminal basin or as an internal drainage system or interior drainage basin. Endorheic regions, in contrast to exorheic regions, which flow to the ocean in geologically defined patterns, are closed hydrologic systems, their surface waters drain to inland terminal locations where the water evaporates or seeps into the ground, having no access to discharge into the sea. Endorheic water bodies include some of the largest lakes in the world, such as the Caspian Sea, the world's largest saline inland sea. Endorheic basins constitute local base levels, defining a limit of erosion and deposition processes of nearby areas; the term comes from the Ancient Greek: ἔνδον, éndon, "within" and ῥεῖν, rheîn, "to flow".
Endorheic lakes are bodies of water. Most of the water falling on Earth finds its way to the oceans through a network of rivers and wetlands. However, there is a class of water bodies that are located in closed or endorheic watersheds where the topography prevents their drainage to the oceans; these endorheic watersheds are called terminal lakes or sink lakes. Endorheic lakes are in the interior of a landmass, far from an ocean in areas of low rainfall, their watersheds are confined by natural geologic land formations such as a mountain range, cutting off water egress to the ocean. The inland water flows into dry watersheds where the water evaporates, leaving a high concentration of minerals and other inflow erosion products. Over time this input of erosion products can cause the endorheic lake to become saline. Since the main outflow pathways of these lakes are chiefly through evaporation and seepage, endorheic lakes are more sensitive to environmental pollutant inputs than water bodies that have access to oceans, as pollution can be trapped in them and accumulate over time.
Endorheic regions can occur in any climate but are most found in desert locations. In areas where rainfall is higher, riparian erosion will carve drainage channels, or cause the water level in the terminal lake to rise until it finds an outlet, breaking the enclosed endorheic hydrological system's geographical barrier and opening it to the surrounding terrain; the Black Sea was such a lake, having once been an independent hydrological system before the Mediterranean Sea broke through the terrain separating the two. Lake Bonneville was another such lake; the Malheur/Harney lake system in Oregon is cut off from drainage to the ocean, but has an outflow channel to the Malheur River, dry, but flows in years of peak precipitation. Examples of humid regions in endorheic basins exist at high elevation; these regions are subject to substantial flooding in wet years. The area containing Mexico City is one such case, with annual precipitation of 850 mm and characterized by waterlogged soils that require draining.
Endorheic regions tend to be far inland with their boundaries defined by mountains or other geological features that block their access to oceans. Since the inflowing water can evacuate only through seepage or evaporation, dried minerals or other products collect in the basin making the water saline and making the basin vulnerable to pollution. Continents vary in their concentration of endorheic regions due to conditions of geography and climate. Australia has the highest percentage of endorheic regions at 21 percent while North America has the least at five percent. 18 percent of the earth's land drains to endorheic lakes or seas, the largest of these land areas being the interior of Asia. In deserts, water inflow is low and loss to solar evaporation high, drastically reducing the formation of complete drainage systems. Closed water flow areas lead to the concentration of salts and other minerals in the basin. Minerals leached from the surrounding rocks are deposited in the basin, left behind when the water evaporates.
Thus endorheic basins contain extensive salt pans. These areas tend to be large, flat hardened surfaces and are sometimes used for aviation runways or land speed record attempts, because of their extensive areas of level terrain. Both permanent and seasonal endorheic lakes can form in endorheic basins; some endorheic basins are stable, climate change having reduced precipitation to the degree that a lake no longer forms. Most permanent endorheic lakes change size and shape over time becoming much smaller or breaking into several smaller parts during the dry season; as humans have expanded into uninhabitable desert areas, the river systems that feed many endorheic lakes have been altered by the construction of dams and aqueducts. As a result, many endorheic lakes in developed or developing countries have contracted resulting in increased salinity, higher concentrations of pollutants, the disruption of ecosystems. Within exorheic basins, there can be "non-contributing", low-lying areas that trap runoff and prevent it from contributing to flows downstream during years of average or below-average runoff.
In flat river basins, non-contributing areas can be a large fraction of the river
The Tibetan Plateau known in China as the Qinghai–Tibet Plateau or the Qing–Zang Plateau or Himalayan Plateau, is a vast elevated plateau in Central Asia and East Asia, covering most of the Tibet Autonomous Region and Qinghai in western China, as well as Ladakh and Lahaul & Spiti in India. It stretches 1,000 kilometres north to south and 2,500 kilometres east to west. With an average elevation exceeding 4,500 metres, the Tibetan Plateau is sometimes called "the Roof of the World" because it stands over 3 miles above sea level and is surrounded by imposing mountain ranges that harbor the world's two highest summits, Mount Everest and K2, is the world's highest and largest plateau, with an area of 2,500,000 square kilometres. Sometimes termed the Third Pole, the Tibetan Plateau contains the headwaters of the drainage basins of most of the streams in surrounding regions, its tens of thousands of glaciers and other geographical and ecological features serve as a "water tower" storing water and maintaining flow.
The impact of global warming on the Tibetan Plateau is of intense scientific interest. The Tibetan Plateau is surrounded by the massive mountain ranges of High-mountain Asia; the plateau is bordered to the south by the inner Himalayan range, to the north by the Kunlun Mountains, which separate it from the Tarim Basin, to the northeast by the Qilian Mountains, which separate the plateau from the Hexi Corridor and Gobi Desert. To the east and southeast the plateau gives way to the forested gorge and ridge geography of the mountainous headwaters of the Salween and Yangtze rivers in northwest Yunnan and western Sichuan. In the west the curve of the rugged Karakoram range of northern Kashmir embraces the plateau; the Indus River originates in the western Tibetan Plateau in the vicinity of Lake Manasarovar. The Tibetan Plateau is bounded in the north by a broad escarpment where the altitude drops from around 5,000 metres to 1,500 metres over a horizontal distance of less than 150 kilometres. Along the escarpment is a range of mountains.
In the west the Kunlun Mountains separate the plateau from the Tarim Basin. About halfway across the Tarim the bounding range becomes the Altyn-Tagh and the Kunluns, by convention, continue somewhat to the south. In the'V' formed by this split is the western part of the Qaidam Basin; the Altyn-Tagh ends near the Dangjin pass on the Dunhuang-Golmud road. To the west are short ranges called the Danghe, Yema and Tulai Nanshans; the easternmost range is the Qilian Mountains. The line of mountains continues east of the plateau as the Qinling, which separates the Ordos Plateau from Sichuan. North of the mountains runs the Gansu or Hexi Corridor, the main silk-road route from China proper to the West; the plateau is a high-altitude arid steppe interspersed with mountain ranges and large brackish lakes. Annual precipitation ranges from 100 to 300 millimetres and falls as hail; the southern and eastern edges of the steppe have grasslands which can sustainably support populations of nomadic herdsmen, although frost occurs for six months of the year.
Permafrost occurs over extensive parts of the plateau. Proceeding to the north and northwest, the plateau becomes progressively higher and drier, until reaching the remote Changtang region in the northwestern part of the plateau. Here the average altitude exceeds 5,000 metres and winter temperatures can drop to −40 °C; as a result of this inhospitable environment, the Changthang region is the least populous region in Asia, the third least populous area in the world after Antarctica and northern Greenland. The geological history of the Tibetan Plateau is related to that of the Himalayas; the Himalayas are among the youngest mountain ranges on the planet and consist of uplifted sedimentary and metamorphic rock. Their formation is a result of a continental collision or orogeny along the convergent boundary between the Indo-Australian Plate and the Eurasian Plate; the collision began in the Upper Cretaceous period about 70 million years ago, when the north-moving Indo-Australian Plate, moving at about 15 cm per year, collided with the Eurasian Plate.
About 50 million years ago, this fast moving Indo-Australian plate had closed the Tethys Ocean, the existence of, determined by sedimentary rocks settled on the ocean floor, the volcanoes that fringed its edges. Since these sediments were light, they crumpled into mountain ranges rather than sinking to the floor; the Indo-Australian plate continues to be driven horizontally below the Tibetan Plateau, which forces the plateau to move upwards. Much of the Tibetan Plateau is of low relief; the cause of this is debated among geologists. Some argue that the Tibetan Plateau is an uplifted peneplain formed at low altitude, while others argue that the low relief stems from erosion and infill of topographic depressions that occurred at high elevations; the Tibetan Plateau supports a variety of most of them classified as montane grasslands. While parts of the plateau feature an alpine tundra-like environment, other areas feature monsoon-influenced shrublands and forests. Species diversity is reduced on the plateau due to the elevation and low precipitation.
The Tibetan Plateau hosts the Tibetan wolf, species of snow leopard, wild yak, wild donkey, vultures, hawk
The Kumtag Desert, is an arid landform in northwestern China, proclaimed as a national park in the year 2002. The oval Tarim Basin with its central Taklamakan Desert is bounded on the north and south by mountains. On the east side the Kumtag is an unbroken plain about 100 miles from north to south that runs from the Taklamakan to Gansu and Mongolia. Many modern maps do not show a Kumtag in this sense; the Kumtag Desert is a section of the Taklamakan Desert which lies east-southeast of the Desert of Lop. It is on the other side of the Kara-koshun and reaches north-eastwards as far as the vicinity of the town of Sa-chow and the lake of Kara-nor, or Kala-chi, it is bordered by Dunhuang in the east, Tian Shan in the north, with an area of 22,800+ square kilometers. Its southern rim is marked by a labyrinth of hills, dotted in groups and irregular clusters,worn down as it were to mere fragments of their former skeletal structure. Between these and the Altyn-Tagh, intervenes a broad latitudinal valley, seamed with watercourses that come down from the foothills of the Altyn-tagh.
Beside these scrubby desert plants of the usual character maintain a precarious existence. Water reaching them in some instances at intervals of years only; this part of the desert has a general slope northwest towards the relative depression of the Kara-koshun. A noticeable feature of the Kumtag is the presence of large accumulations of drift-sand along the foot of the crumbling desert ranges, where it rises into dunes sometimes as much as 250 feet in height and climbs halfway up the flanks of ranges themselves. Administratively, the desert is located in the Ruoqiang County of Xinjiang and Aksai Kazakh Autonomous County and Dunhuang City of Gansu, near their border with Qinghai. A map published by the National Geographic Society shows a much smaller Kumtag; this is a rectangle with a northwest corner south of Lop Nor, a southern edge along the Altyn-Tagh and an eastern edge just beyond the Gansu border. Near the northeast corner is the Jade Gate, taken as the eastern end of the Great Wall. From space it appears as a belt of orange sand dunes.
This is the 2500 square kilometer area mentioned below. The Kumtag Desert is expanding and threatening to engulf productive lands with its arid wasteland character. Several years prior the estimated size of the desert was 2500 square kilometres, but with recent expansion, the Kumtag Desert is considerably larger as of 2008; the Kumtag Desert is continuing a process of expansion, the result of centuries of overgrazing of this region, beyond its carrying capacity. According to the AFP news report of November, 2007: "Towering sand dunes loom over the ancient Chinese city of Dunhuang". According to Hogan: "Rapid expansion of the Kumtag Desert and other dunes formations threaten to engulf Yungang and other archaeological sites". To mitigate the desertification, the town of Dunhuang has placed severe limitations on immigration, has placed restrictions on new water-well development or new farm additions; the prevailing winds in this region would appear to blow from the west and northwest during the summer and autumn.
Though in spring, when they are more violent, they no doubt come from the northeast, as in the desert of Lop. The arrangement of the sand here agrees with the law laid down by Grigory Potanin, that in the basins of Central Asia the sand is heaped up in greater mass on the south, all along the bordering mountain ranges where the floor of the depressions lies at the highest level; the country to the north of the desert ranges is thus summarily described by Sven Hedin: "The first zone of drift sand is succeeded by a region that exhibits proofs of wind modelling on an extraordinarily energetic and well-developed scale, the results corresponding to the jardangs and the wind-eroded gullies of the Desert of Lop. Both sets of phenomena lie parallel to one another. Next comes demarcated from the zone just described, a more or less thin kamish steppe growing on level ground. "At the points where we measured them the northern terrace was 113 feet high and the southern 853/4 feet.... Both terraces belong to the same level, would appear to correspond to the shore lines of a big bay of the last surviving remnant of the Central Asian Mediterranean.
At the point where I crossed it the depression was 6 to 7 miles and thus resembled a flat valley or immense river-bed."The moving sands of the Kumtag are of a concern for the designers of the Golmud–Dunhuang Railway, which will cross the eastern edge of this desert in the Shashangou area, between Dunhuang and the Altyn-Tagh-Qilian mountain system. There was a concern. However, geological research indicated that the "megadunes" are formed by solid subsoil, rather than just sand. Although there is still the issue of drifting sand, it is thought by the experts that
Qinghai, is a province of the People's Republic of China located in the northwest of the country. As one of the largest province-level administrative divisions of China by area, the province is ranked fourth-largest in area, has the third-smallest population. Located on the Tibetan Plateau, the province has long been a melting pot for a number of ethnic groups including the Han, Hui, Tu, Salars. Qinghai borders Gansu on the northeast, Xinjiang on the northwest, Sichuan on the southeast, the Tibet Autonomous Region on the southwest. Qinghai province was established in 1928 under the Republic of China period during which it was ruled by Chinese Muslim warlords known as the Ma clique; the Chinese name, "Qinghai" is named after the largest lake in China. The province was known as Kokonur in English, derived from the Oirat name for Qinghai Lake. During China's Bronze Age, Qinghai was home to the Qiang people who traditionally made a living in agriculture and husbandry, the Kayue culture; the eastern part of the area of Qinghai was under the control of the Han dynasty about 2000 years ago.
It was a battleground during the Tang and subsequent Chinese dynasties when they fought against successive Tibetan tribes. In the middle of 3rd century CE, nomadic people related to the Mongolic Xianbei migrated to pasture lands around the Qinghai Lake and established the Tuyuhun Kingdom. In the 7th century, Tuyuhun Kingdom was attacked by both the Tibetan Empire and Tang dynasty as both of them sought control over trade routes. Military conflicts weakened the kingdom and it was incorporated into the Tibetan Empire. After the disintegration of the Tibetan Empire, small local factions emerged, some under the titular authority of China; the Song dynasty defeated the Tibetan Kokonor Kingdom in the 1070s. During the Yuan dynasty's administrative rule of Tibet, the region comprising the headwaters of the Yellow and Yangtze rivers - what modern Tibetan nationalists call "Amdo" - was apportioned to different administrative divisions than Tibet proper. Most of Qinghai was once a short time under the control of early Ming dynasty, but gradually lost to the Khoshut Khanate founded by the Oirats.
The Xunhua Salar Autonomous County is. The Salars migrated to Qinghai from Samarkand in 1370; the chief of the four upper clans around this time was Han Pao-yuan and Ming granted him office of centurion, it was at this time the people of his four clans took Han as their surname. The other chief Han Shan-pa of the four lower Salar clans got the same office from Ming, his clans were the ones who took Ma as their surname. From 1640 to 1724, a big part of the area, now Qinghai was under Khoshut Mongol control, but in that year it was conquered by the armies of the Qing dynasty, it was during the 1720s when Xining Prefecture was established and its borders were those of modern Qinghai province. Xining, the capital of modern Qinghai province was built in this period as the administrative center. During the rule of the Qing dynasty, the governor was a viceroy of the Qing Emperor, but the local ethnic groups enjoyed much autonomy. Many chiefs retained their traditional authority; the Dungan revolt devastated the Hui Muslim population of Shaanxi, shifting the Hui center of population to Gansu and Qinghai.
Another Dungan revolt broke out in Qinghai in 1895 when various Muslim ethnic groups in Qinghai and Gansu rebelled against the Qing. Following the overthrow of the Qing dynasty in 1911, the region came under Chinese Muslim warlord Ma Qi control until the Northern Expedition by the Republic of China consolidated central control in 1928. In July–August 1912, General Ma Fuxiang was "Acting Chief Executive Officer of Kokonur". In 1928, Qinghai province was created, it was part of Gansu, as the "Tibetan frontier district". The Muslim warlord and General Ma Qi became military governor of Qinghai, followed by his brother Ma Lin and Ma Qi's son Ma Bufang. In 1932 Tibet invaded Qinghai, attempting to capture southern parts of Qinghai province, following contention in Yushu, Qinghai over a monastery in 1932; the army of Ma Bufang's defeated the Tibetan armies. Governor of Qinghai, Ma Bufang was described as a socialist by American journalist John Roderick and friendly compared to the other Ma Clique warlords.
Ma Bufang was reported to be jovial in contrast to the brutal reign of Ma Hongkui. Most of eastern China was ravaged by the Second Sino-Japanese War and the Chinese Civil War, by contrast, Qinghai was untouched. Ma Bufang increased the prominence of the Hui and Salar people in Qinghai's politics by recruiting to his army from the counties in which those ethnic groups predominated. General Ma started a state run and controlled industrialization project, directly creating educational, medical and sanitation projects, run or assisted by the state; the state provided money for food and uniforms in state run or private. Roads and a theater were constructed; the state controlled all the press, no freedom was allowed for independent journalists. As the 1949 Chinese revolution approached Qinghai, Ma Bufang abandoned his post and flew to Hong Kong, traveling abroad but never returning to China. On January 1, 1950, the Qinghai Province People's Government was declared, owing its allegiance to the new People's Republic of China.
Aside from some minor adjustments to suit the geography, the PRC maintained the province's territorial integrity. Resistance to Communist rule continued in the form of the Huis' Kuomintang Islamic insurgency
China National Highway 315
Constructed in 1954, the Qinghai-Xinjiang Highway known as the China National Highway 315 runs west from Xining, Qinghai towards Kashgar, Xinjiang. It is 3,063 kilometres in length. In 1994 the departments of communication and transportation in Qinghai and Xinjiang began the process of updating the highway. In the west it follows the desert Qaidam Basin south of the traditional Silk Road, crosses the Altyn-Tagh into Xinjiang, follows the south side of the Tarim Basin to Kashgar. China National Highways
Hexi Corridor or Gansu Corridor refers to the historical route in Gansu province of China. As part of the Northern Silk Road running northwest from the bank of the Yellow River, it was the most important route from North China to the Tarim Basin and Central Asia for traders and the military; the corridor is a string of oases along the northern edge of the Tibetan Plateau. To the south is the high and desolate Tibetan Plateau and to the north, the Gobi Desert and the grasslands of Outer Mongolia. At the west end the route splits in three, going either north of the Tian Shan or south on either side of the Tarim Basin. At the east end are mountains around Lanzhou before one reaches the Wei River valley and China proper. Cultivated wheat, originating at the Fertile Crescent appeared in China around 2800 BC at Donghuishan at the Hexi corridor. Several other crops are attested at this time period. Xishanping is another similar site in Gansu. According to Dodson et al. wheat entered via the Hexi Corridor into northern Gangsu around 3000 BC, although other scholars date this somewhat later.
The Chinese millets, rice, as well as other crops travelled the opposite way through the Corridor, reached western Asia and Europe from the fifth millennium to the second millennium BC. As early as the 1st millennium BCE, silk goods began appearing in Siberia, having traveled over the Northern branch of the Silk Road, including the Hexi Corridor segment. At the end of the Qin dynasty, the Yuezhi overcame previous settlers, the Wusun and Qiang, occupying the western Hexi Corridor. Northern Xiongnu armies vanquished the Yuezhi and established dominance here during the early Han dynasty. During the Han–Xiongnu War, Han China expelled the Xiongnu from the Hexi Corridor in 121 BCE and drove them from Lop Nur when King Hunye surrendered to Huo Qubing in 121 BCE; the Han acquired a territory stretching from the Hexi Corridor to Lop Nur, thus cutting the Xiongnu off from their Qiang allies. Again, Han forces repelled a joint Xiongnu-Qiang invasion of this northwestern territory in 111 BCE. After 111 BCE, new outposts were established, four of them in the Hexi Corridor, namely Jiuquan, Zhangye and Guzang.
From 115–60 BCE, Han forces fought the Xiongnu over control of the oasis city-states in the Tarim Basin. Han was victorious and established the Protectorate of the Western Regions in 60 BCE, which dealt with the region's defense and foreign affairs. During the turbulent reign of Wang Mang, Han lost control over the Tarim Basin, conquered by the Xiongnu in 63 CE, used as a base to invade the Hexi Corridor. Dou Gu defeated the Xiongnu again at the Battle of Yiwulu in 73 CE, evicting them from Turpan and chasing them as far as Lake Barkol before establishing a garrison at Hami. After the new Protector General of the Western Regions Chen Mu was killed in 75 CE by allies of the Xiongnu in Karasahr and Kucha, the garrison at Hami was withdrawn. At the Battle of the Altai Mountains in 89 CE, Dou Xian defeated the Northern Chanyu, who retreated into the Altai Mountains; the Tang dynasty fought the Tibetan Empire for control of areas in Central Asia. There was a long string of conflicts with Tibet over territories in the Tarim Basin between 670–692.
In 763 the Tibetans captured the Tang capital of Chang'an for fifteen days during the An Lushan Rebellion. It was during this rebellion that the Tang withdrew its western garrisons stationed in what is now Gansu and Qinghai, which the Tibetans occupied along with the area, modern Xinjiang. Hostilities between the Tang and Tibet continued until they signed a formal peace treaty in 821; the terms of this treaty, including fixed borders between the two countries, are recorded in a bilingual inscription on a stone pillar outside the Jokhang in Lhasa. The Western Xia Dynasty, known as the Tangut Empire, was established in the 11th century by Tangut tribes. Western Xia controlled from 1038 CE up to 1227 CE the areas in what are now the northwestern Chinese provinces of Gansu and Ningxia. Genghis Khan began the Mongol conquest of the Jin dynasty around 1207 and Ögedei Khan continued it after his death in 1227; the Jin dynasty of the Jurchen people fell in 1234 CE with help from the Han Chinese dynasty of the Southern Song.
Ögedei crushed the Western Xia in 1227, pacifying the Hexi Corridor region, controlled by the Yuan dynasty established by Kublai Khan, the fifth Khagan of the Mongol Empire. The Yuan lasted from 1271-1368; the Hexi Corridor is a long, narrow passage stretching for some 1,000 kilometres from the steep Wushaolin hillside near the modern city of Lanzhou to the Jade Gate at the border of Gansu and Xinjiang. There are many fertile oases along the path, watered by rivers flowing from the Qilian Mountains, such as the Shiyang, Jinchuan and Shule Rivers. A strikingly inhospitable environment surrounds this chain of oases: the snow-capped Qilian Mountains to the south. Geologically, the Hexi Corridor belongs to a Cenozoic foreland basin system on the northeast margin of the Tibetan Plateau; the ancient trackway passed through Haidong and the environs of Juyan Lake, serving an effective area of about 215,000 km2. It was an area where mountain and desert limited caravan traffic to a narrow trackway, where small fortifications could control passing traffic.
There are several major cities along the Hexi Corridor. In western Gansu Province is Dunhuang