1.
White Mountains (New Hampshire)
–
The White Mountains are a mountain range covering about a quarter of the state of New Hampshire and a small portion of western Maine in the United States. They are part of the northern Appalachian Mountains and the most rugged mountains in New England, the range is heavily visited due to its proximity to Boston and, to a lesser extent, New York City and Montreal. Most of the area is land, including the White Mountain National Forest. Its most famous mountain is 6, 288-foot Mount Washington, which is the highest peak in the Northeastern U. S. Mount Washington is part of a line of summits, the Presidential Range, that are named after U. S. presidents and other prominent Americans. The White Mountains also include the Franconia Range, Sandwich Range, Carter-Moriah Range and Kinsman Range in New Hampshire, in all, there are 48 peaks within New Hampshire as well as one in Maine over 4,000 feet, known as the Four-thousand footers. The Whites are known for a system of alpine huts for hikers operated by the Appalachian Mountain Club, the Appalachian Trail crosses the area from southwest to northeast. It is not clear where the name White Mountains came from, there is no record of what Native Americans called the range, although pre-Colonial names for many individual peaks are known. The name and similar such as White Hills or Wine Hills are found in literature from Colonial times. According to tradition, the mountains were first sighted from shipboard off the coast near the Piscataqua estuary, the highest peaks would often be snow-capped, appearing white. An alternate theory is that the granite of the summits looked white to observers. The White Mountains are a section of the larger New England province. The magma intrusions forming the White Mountains today were created 124 to 100 million years ago as the North American Plate moved westward over the New England hotspot, widespread evidence of glaciation may be seen in the U-shaped form of various notches, or mountain passes. Glacial cirques form the heads of Tuckerman Ravine on Mt. Washington, glacial striations are visible at numerous locations, including on the exposed rocks at the summit of Pine Mountain in Gorham. The Mount Washington Auto Road and the historic Mount Washington Cog Railway ascend the ranges highest peak, heavily visited Arethusa Falls, the second tallest waterfall in New Hampshire, lies on a southwest flank of Crawford Notch. The Old Man of the Mountain, a formation on Cannon Mountain that resembled the craggy profile of a mans face, was a White Mountain landmark until it fell in May 2003. It remains the symbol of New Hampshire. The range also includes a feature dubbed The Basin, consisting of a granite bowl,20 feet in diameter, fed by a waterfall. The areas around The Basin are popular spots for swimming in the ice-cold mountain-fed water, some of the earliest maps of the White Mountains were produced as tourist maps and not topographical maps
2.
Elevation
–
GIS or geographic information system is a computer system that allows for visualizing, manipulating, capturing, and storage of data with associated attributes. GIS offers better understanding of patterns and relationships of the landscape at different scales, tools inside the GIS allow for manipulation of data for spatial analysis or cartography. A topographical map is the type of map used to depict elevation. In a Geographic Information System, digital models are commonly used to represent the surface of a place. Digital terrain models are another way to represent terrain in GIS, USGS is developing a 3D Elevation Program to keep up with growing needs for high quality topographic data. 3DEP is a collection of enhanced elevation data in the form of high quality LiDAR data over the conterminous United States, Hawaii, there are three bare earth DEM layers in 3DEP which are nationally seamless at the resolution of 1/3,1, and 2 arcseconds. This map is derived from GTOPO30 data that describes the elevation of Earths terrain at intervals of 30 arcseconds and it uses color and shading instead of contour lines to indicate elevation. Hypsography is the study of the distribution of elevations on the surface of the Earth, the term originates from the Greek word ὕψος hypsos meaning height. Most often it is used only in reference to elevation of land, related to the term hypsometry, the measurement of these elevations of a planets solid surface are taken relative to mean datum, except for Earth which is taken relative to the sea level. In the troposphere, temperatures decrease with altitude and this lapse rate is approximately 6.5 °C/km. S
3.
Tundra
–
In physical geography, tundra is a type of biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr uplands, there are three types of tundra, Arctic tundra, alpine tundra, and Antarctic tundra. In tundra, the vegetation is composed of shrubs, sedges and grasses, mosses. Scattered trees grow in tundra regions. The ecotone between the tundra and the forest is known as the line or timberline. Arctic tundra occurs in the far Northern Hemisphere, north of the taiga belt, the word tundra usually refers only to the areas where the subsoil is permafrost, or permanently frozen soil. Permafrost tundra includes vast areas of northern Russia and Canada, the polar tundra is home to several peoples who are mostly nomadic reindeer herders, such as the Nganasan and Nenets in the permafrost area. Arctic tundra contains areas of landscape and is frozen for much of the year. The soil there is frozen from 25–90 cm down, and it is impossible for trees to grow, instead, bare and sometimes rocky land can only support low growing plants such as moss, heath, and lichen. There are two seasons, winter and summer, in the polar tundra areas. During the winter it is cold and dark, with the average temperature around −28 °C. However, extreme temperatures on the tundra do not drop as low as those experienced in taiga areas further south. During the summer, temperatures rise somewhat, and the top layer of seasonally-frozen soil melts, the tundra is covered in marshes, lakes, bogs and streams during the warm months. Generally daytime temperatures during the rise to about 12 °C. Arctic tundras are sometimes the subject of conservation programs. In Canada and Russia, many of areas are protected through a national Biodiversity Action Plan. Tundra tends to be windy, with winds often blowing upwards of 50–100 km/h, however, in terms of precipitation, it is desert-like, with only about 15–25 cm falling per year. Although precipitation is light, evaporation is also relatively minimal, there is a natural pattern of accumulation of fuel and wildfire which varies depending on the nature of vegetation and terrain
4.
Tree line
–
The tree line is the edge of the habitat at which trees are capable of growing. It is found at high elevations and in frigid environments, beyond the tree line, trees cannot tolerate the environmental conditions. The tree line should not be confused with a lower timberline or forest line, at the tree line, tree growth is often sparse and stunted, with the last trees forming densely matted bushes, known as krummholz. The tree line, like other natural lines, appears well-defined from a distance. Trees grow shorter towards the inhospitable climate until they stop growing. The climate above the line of mountains is called an alpine climate. In the northern hemisphere treelines on north-facing slopes are lower than on south-facing slopes because the increased shade on north-facing slopes means the snowpack takes longer to melt and this shortens the growing season for trees. In the southern hemisphere, the slopes have the shorter growing season. The alpine tree line boundary is seldom abrupt, it forms a transition zone between closed forest below and treeless alpine tundra above. Environmentally dwarfed shrubs commonly forms the upper limit, the decrease in air temperature due to increasing elevation causes the alpine climate. Skin effects and topography can create microclimates that alter the general cooling trend, however, the number of degree days calculated from leaf temperatures may be very similar in the two kinds of timberlines. A series of warm summers in the 1940s seems to have permitted the establishment of “significant numbers” of spruce seedlings above the treeline in the hills near Fairbanks. Survival depends on a sufficiency of new growth to support the tree, the windiness of high-elevation sites is also a potent determinant of the distribution of tree growth. However, snow accumulation in sheltered gullies in the Selkirk Mountains of southeastern British Columbia causes timberline to be 400 metres lower than on exposed intervening shoulders. In a desert, the line marks the driest places where trees can grow. These tend to be called the tree line and occur below about 5,000 ft elevation in the Desert Southwestern United States. In some mountainous areas, higher elevations above the line or on equator-facing and leeward slopes can result in low rainfall. This dries out the soil, resulting in an arid environment unsuitable for trees
5.
Himalayas
–
The Himalayas, or Himalaya, form a mountain range in Asia separating the plains of the Indian subcontinent from the Tibetan Plateau. The Himalayan range has the Earths highest peaks, including the highest, the Himalayas include over a hundred mountains exceeding 7,200 metres in elevation. By contrast, the highest peak outside Asia – Aconcagua, in the Andes – is 6,961 metres tall. The Himalayas are spread across five countries, Bhutan, India, Nepal, China, the Himalayan range is bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by the Tibetan Plateau, and on the south by the Indo-Gangetic Plain. Some of the major rivers, the Indus, the Ganges, and the Tsangpo-Brahmaputra, rise in the Himalayas. The Himalayas have profoundly shaped the cultures of South Asia, many Himalayan peaks are sacred in Hinduism and Buddhism. Lifted by the subduction of the Indian tectonic plate under the Eurasian Plate and its western anchor, Nanga Parbat, lies just south of the northernmost bend of Indus river. Its eastern anchor, Namcha Barwa, is just west of the bend of the Tsangpo river. The range varies in width from 400 kilometres in the west to 150 kilometres in the east, the name of the range derives from the Sanskrit Himā-laya, from himá and ā-laya. They are now known as the Himalaya Mountains, usually shortened to the Himalayas, formerly, they were described in the singular as the Himalaya. This was also previously transcribed Himmaleh, as in Emily Dickinsons poetry and Henry David Thoreaus essays. The mountains are known as the Himālaya in Nepali and Hindi, the Himalaya or The Land of Snow in Tibetan, the Hamaleh Mountain Range in Urdu, the flora and fauna of the Himalayas vary with climate, rainfall, altitude, and soils. The climate ranges from tropical at the base of the mountains to permanent ice, the amount of yearly rainfall increases from west to east along the southern front of the range. This diversity of altitude, rainfall and soil conditions combined with the high snow line supports a variety of distinct plant. The extremes of high altitude combined with extreme cold favor extremophile organisms, the unique floral and faunal wealth of the Himalayas is undergoing structural and compositional changes due to climate change. The increase in temperature is shifting various species to higher elevations, the oak forest is being invaded by pine forests in the Garhwal Himalayan region. There are reports of early flowering and fruiting in some species, especially rhododendron, apple. The highest known tree species in the Himalayas is Juniperus tibetica located at 4,900 metres in Southeastern Tibet, the Himalayan range is one of the youngest mountain ranges on the planet and consists mostly of uplifted sedimentary and metamorphic rock
6.
Alps
–
The mountains were formed over tens of millions of years as the African and Eurasian tectonic plates collided. Extreme shortening caused by the event resulted in marine sedimentary rocks rising by thrusting and folding into high mountain peaks such as Mont Blanc, Mont Blanc spans the French–Italian border, and at 4,810 m is the highest mountain in the Alps. The Alpine region area contains about a hundred peaks higher than 4000 metres, the altitude and size of the range affects the climate in Europe, in the mountains precipitation levels vary greatly and climatic conditions consist of distinct zones. Wildlife such as live in the higher peaks to elevations of 3,400 m. Evidence of human habitation in the Alps goes back to the Palaeolithic era, a mummified man, determined to be 5,000 years old, was discovered on a glacier at the Austrian–Italian border in 1991. By the 6th century BC, the Celtic La Tène culture was well established, Hannibal famously crossed the Alps with a herd of elephants, and the Romans had settlements in the region. In 1800 Napoleon crossed one of the passes with an army of 40,000. The 18th and 19th centuries saw an influx of naturalists, writers, in World War II, Adolf Hitler kept a base of operation in the Bavarian Alps throughout the war. The Alpine region has a cultural identity. The Winter Olympic Games have been hosted in the Swiss, French, at present, the region is home to 14 million people and has 120 million annual visitors. The English word Alps derives from the Latin Alpes, maurus Servius Honoratus, an ancient commentator of Virgil, says in his commentary that all high mountains are called Alpes by Celts. The term may be common to Italo-Celtic, because the Celtic languages have terms for high mountains derived from alp and this may be consistent with the theory that in Greek Alpes is a name of non-Indo-European origin. According to the Old English Dictionary, the Latin Alpes might possibly derive from a pre-Indo-European word *alb hill, Albania, a name not native to the region known as the country of Albania, has been used as a name for a number of mountainous areas across Europe. In Roman times, Albania was a name for the eastern Caucasus, in modern languages the term alp, alm, albe or alpe refers to a grazing pastures in the alpine regions below the glaciers, not the peaks. An alp refers to a mountain pasture where cows are taken to be grazed during the summer months and where hay barns can be found. The Alps are a crescent shaped geographic feature of central Europe that ranges in a 800 km arc from east to west and is 200 km in width, the mean height of the mountain peaks is 2.5 km. The range stretches from the Mediterranean Sea north above the Po basin, extending through France from Grenoble, the range continues onward toward Vienna, Austria, and east to the Adriatic Sea and Slovenia. To the south it dips into northern Italy and to the north extends to the border of Bavaria in Germany
7.
Scandinavian Mountains
–
The Scandinavian Mountains or the Scandes is a mountain range that runs through the Scandinavian Peninsula. The Scandinavian Mountains are often thought to be equivalent to the Scandinavian Caledonides. The western sides of the mountains drop precipitously into the North Sea and Norwegian Sea, forming the fjords of Norway, to the north they form the border between Norway and Sweden, still reaching 2,000 m high at the Arctic Circle. The mountain range just touches northwesternmost Finland, but are more than hills at their northernmost extension at the North Cape. The combination of a location and moisture from the North Atlantic Ocean has caused the formation of many ice fields. In Northern Norway, permafrost becomes common from about 800 to 900 meters AMSL on the western slope, the Scandinavian Montane Birch forest and grasslands terrestrial ecoregion is closely associated with the mountain range. Its names in the Scandinavian languages are, in Swedish Skandinaviska fjällkedjan, Skanderna, Fjällen or Kölen, the names Kölen and Kjølen are often preferentially used for the northern part, where the mountains form a narrow range near the border region of Norway and Sweden. In southern Norway there is a scatter of mountain regions with individual names, such as Dovrefjell, Hardangervidda, Jotunheimen. The mountain chains highest summits are mostly concentrated in an area between Stavanger and Trondheim in southern Norway, with peaks over 1300 m and some peaks over 2000 m. Around Trondheim Fjord peaks decrease in altitude to about 400–500 m rising again to heights in excess of 1900 m further north in Swedish Lapland, the southern part of the mountain range contains the highest mountain of Northern Europe, Galdhøpiggen at almost 2500 m. This part of the chain is also broader and contains a series of plateaux. In south-western Norway the plateaux and gently undulating surfaces are strongly dissected by fjords, the mountain chain is present in Sweden from northern Dalarna northwards, south of this point the Scandinavian Mountains lie completely within Norway. Most of the Scandinavian Mountains lack alpine topography, and where it does have it does relate to altitude, to the east the Scandinavian Mountains proper bounds with mountains that are lower and less dissected and are known as the förfjäll. Generally the förfjäll do not surpass 1000 m. a. s. l, as a geomorphic unit the förfjäll extends across Sweden as a 650 km long and 40 to 80 km broad belt from Dalarna in the south to Norrbotten in the north. The origin of mountain topography is debated by geologists. In Scandinavia the Caledonian Mountains begun a post-orogenic collapse in the Devonian implying tectonic extension, despite occurring in about the same area the ancient Caledonian Mountains and the modern Scandinavian Mountains are unrelated. The Scandinavian Mountains attained its height by tectonic processes different from orogeny, a two-stage model of uplift has been proposed for the Scandinavian Mountains in southern Norway. A first stage in the Mesozoic and a stage starting from the Oligocene
8.
Pyrenees
–
The Pyrenees is a range of mountains in southwest Europe that forms a natural border between France and Spain. For the most part, the main crest forms a divide between France and Spain, with the microstate of Andorra sandwiched in between. The Crown of Aragon and the Kingdom of Navarre have historically extended on both sides of the range, with smaller northern portions now in France and larger southern parts now in Spain. The demonym for the noun Pyrenees in English is Pyrenean, in Greek mythology, Pyrene is a princess who gave her name to the Pyrenees. The Greek historian Herodotus says Pyrene is the name of a town in Celtic Europe, Hercules, characteristically drunk and lustful, violates the sacred code of hospitality and rapes his hosts daughter. Pyrene gives birth to a serpent and runs away to the woods, alone, she pours out her story to the trees, attracting the attention of wild beasts who tear her to pieces. After his victory over Geryon, Hercules passes through the kingdom of Bebryx again, and all the rock-cliffs and wild-beast haunts echo back Pyrene. … The mountains hold on to the name through the ages. Pliny the Elder connects the story of Hercules and Pyrene to Lusitania, the Spanish Pyrenees are part of the following provinces, from east to west, Girona, Barcelona, Lleida, Huesca, Navarra and Gipuzkoa. The French Pyrenees are part of the following départements, from east to west, Pyrénées-Orientales, Aude, Ariège, Haute-Garonne, Hautes-Pyrénées, the independent principality of Andorra is sandwiched in the eastern portion of the mountain range between the Spanish Pyrenees and French Pyrenees. Physiographically, the Pyrenees may be divided into three sections, the Atlantic, the Central, and the Eastern Pyrenees, together, they form a distinct physiographic province of the larger Alpine System division. In the Western Pyrenees, from the Basque mountains near the Bay of Biscay of the Atlantic Ocean, at the eastern end on the southern side lies a distinct area known as the Sub-Pyrenees. On the French side the slopes of the range descend abruptly. The Pyrenees are older than the Alps, their sediments were first deposited in coastal basins during the Paleozoic and Mesozoic eras, the intense pressure and uplifting of the Earths crust first affected the eastern part and moved progressively to the entire chain, culminating in the Eocene Epoch. The eastern part of the Pyrenees consists largely of granite and gneissose rocks, the massive and unworn character of the chain comes from its abundance of granite, which is particularly resistant to erosion, as well as weak glacial development. Low passes are lacking, and the roads and the railroads between France and Spain run only in the lowlands at the western and eastern ends of the Pyrenees. A notable visual feature of mountain range is La Brèche de Roland, a gap in the ridge line. Coal deposits capable of being profitably worked are situated chiefly on the Spanish slopes, the open pit of Trimoun close to the commune of Luzenac is one of the greatest sources of talc in Europe
9.
Carpathian Mountains
–
The Carpathian Mountains or Carpathians are a mountain range system forming an arc roughly 1,500 km long across Central and Eastern Europe, making them the second-longest mountain range in Europe. The Carpathians and their foothills also have many thermal and mineral waters, the Carpathians consist of a chain of mountain ranges that stretch in an arc from the Czech Republic in the northwest through Slovakia, Poland, Hungary and Ukraine to Romania and Serbia. The highest range within the Carpathians is the Tatras, on the border of Slovakia and Poland, the second-highest range is the Southern Carpathians in Romania, where the highest peaks exceed 2,500 m. The divisions of the Carpathians are usually in three sections, Western Carpathians — Czech Republic, Poland, and Slovakia. Eastern Carpathians — southeastern Poland, eastern Slovakia, Ukraine, Romania, the term Outer Carpathians is frequently used to describe the northern rim of the Western and Eastern Carpathians. The most important cities in or near the Carpathians are, Bratislava and Košice in Slovakia, Kraków in Poland, Cluj-Napoca, Sibiu and Braşov in Romania, and Uzhhorod in Ukraine. In modern times, the range is called Karpaty in Czech, Polish, Slovak and Карпати in Ukrainian, Carpați in Romanian, Karpaten in German, Kárpátok in Hungarian and Karpati or Карпати in Serbian. Although the toponym was recorded already by Ptolemy in the 2nd century CE, for instance, Havasok was its medieval Hungarian name, Rus and Romanian chronicles referred to it as Hungarian Mountains. The archaic Polish word karpa meant rugged irregularities, underwater obstacles/rocks, the more common word skarpa means a sharp cliff or other vertical terrain. In late Roman documents, the Eastern Carpathian Mountains were referred to as Montes Sarmatici, the Western Carpathians were called Carpates, a name that is first recorded in Ptolemys Geographia. In the Scandinavian Hervarar saga, which relates ancient Germanic legends about battles between Goths and Huns, the name Karpates appears in the predictable Germanic form as Harvaða fjöllum, inter Alpes Huniae et Oceanum est Polonia by Gervase of Tilbury, has described in his Otia Imperialia in 1211. Thirteenth- to fifteenth-century Hungarian documents named the mountains Thorchal, Tarczal or less frequently Montes Nivium, the northwestern Carpathians begin in Slovakia and southern Poland. They surround Transcarpathia and Transylvania in a semicircle, sweeping towards the southeast. The total length of the Carpathians is over 1,500 km, the highest altitudes of the Carpathians occur where they are widest. The Carpathians cover an area of 190,000 km2 and, after the Alps, although commonly referred to as a mountain chain, the Carpathians do not actually form an uninterrupted chain of mountains. Rather, they consist of several orographically and geologically distinctive groups, the Carpathians at their highest altitude are only as high as the middle region of the Alps, with which they share a common appearance, climate, and flora. The Carpathians are separated from the Alps by the Danube, the two ranges meet at only one point, the Leitha Mountains at Bratislava. The river also separates them from the Balkan Mountains at Orşova in Romania, the valley of the March and Oder separates the Carpathians from the Silesian and Moravian chains, which belong to the middle wing of the great Central Mountain System of Europe
10.
Caucasus Mountains
–
The Caucasus Mountains are a mountain system in Eurasia between the Black Sea and the Caspian Sea in the Caucasus region. The Caucasus Mountains include the Greater Caucasus in the north and Lesser Caucasus in the south, the Greater Caucasus runs west-northwest to east-southeast, from the Caucasian Natural Reserve in the vicinity of Sochi on the northeastern shore of the Black Sea nearly to Baku on the Caspian Sea. The Lesser Caucasus runs parallel to the Greater about 100 km south, the Greater and Lesser Caucasus ranges are connected by the Likhi Range, and to the west and east of the Likhi Range lie the Colchis Plain and the Kur-Araz Lowland. The Meskheti Range is a part of the Lesser Caucasus system, in the southeast the Aras River separates the Lesser Caucasus from the Talysh Mountains which straddle the border of southeastern Azerbaijan and Iran. The highest peak in the Caucasus range is Mount Elbrus in the Greater Caucasus, Mountains near Sochi hosted part of the 2014 Winter Olympics. Geologically, the Caucasus Mountains belong to a system that extends from southeastern Europe into Asia, the Greater Caucasus Mountains are mainly composed of Cretaceous and Jurassic rocks with the Paleozoic and Precambrian rocks in the higher regions. Some volcanic formations are found throughout the range, on the other hand, the Lesser Caucasus Mountains are formed predominantly of the Paleogene rocks with a much smaller portion of the Jurassic and Cretaceous rocks. The Caucasus Mountains formed largely as the result of a plate collision between the Arabian plate moving northwards with respect to the Eurasian plate. As this happened, the rocks that had been deposited in this basin from the Jurassic to the Miocene were folded to form the Greater Caucasus Mountains. This collision also caused the uplift and the Cenozoic volcanic activity in the Lesser Caucasus Mountains, the entire region is regularly subjected to strong earthquakes from this activity. While the Greater Caucasus Mountains have a mainly folded sedimentary structure, the Javakheti Volcanic Plateau in Georgia and the surrounding volcanic ranges which extend well into central Armenia are some of the youngest features of the region. The Kazbek is no active, but the Elbrus erupted in postglacial times. Contemporary seismic activity is a prominent feature of the region, reflecting active faulting, clusters of seismicity occur in Dagestan and in northern Armenia. Many devastating earthquakes have been documented in historical times, including the Spitak earthquake in December 1988 which destroyed the Gyumri-Vanadzor region of Armenia, europes highest mountain is Mount Elbrus 5,642 m in the Caucasus Mountains. Elbrus is 832 m higher than Mont Blanc, the highest peak in the Alps at 4,810 m, the Caucasus Mountains are defined as the continental divide between Asia and Europe for the region between the Black and Caspian Seas. The table below lists some of the highest peaks of the Caucasus, with the exception of Shkhara, the heights are taken from Soviet 1,50,000 mapping. There are higher and more prominent, but nameless, peaks than some of the peaks included below, the climate of the Caucasus varies both vertically and horizontally. Temperature generally decreases as elevation rises, average annual temperature in Sukhumi, Abkhazia at sea level is 15 °C while on the slopes of Mt. Kazbek at an elevation of 3,700 metres, average annual temperature falls to−6.1 °C
11.
Tibetan Plateau
–
It stretches approximately 1,000 kilometres north to south and 2,500 kilometres east to west. Sometimes termed the Third Pole, the Tibetan Plateau contains the headwaters of the 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, the impact of global warming on the Tibetan Plateau is of intense scientific interest. The Tibetan Plateau is surrounded by mountain ranges. 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 Mansarovar. The Tibetan Plateau is bounded in the north by an 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, 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, Shule, and Tulai Nanshans. The easternmost range is the Qilian Mountains, the line of mountains continues east of the plateau as the Qin Mountains which separate the Ordos Region from Sichuan. North of the runs the Gansu or Hexi Corridor which was the main silk-road route from China proper to the West. The plateau is an arid steppe interspersed with mountain ranges. Annual precipitation ranges from 100 to 300 millimetres and falls mainly 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 parts of the plateau. Proceeding to the north and northwest, the plateau becomes progressively higher, colder and drier, here the average altitude exceeds 5,000 metres and winter temperatures can drop to −40 °C. The geological history of the Tibetan Plateau is closely related to that of the Himalayan mountain range, the Himalayas are among the youngest mountain ranges on the planet and consist mostly of uplifted sedimentary and metamorphic rock. Their formation is a result of a 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, since these sediments were light, they crumpled into mountain ranges rather than sinking to the floor
12.
Ocean
–
An ocean is a body of saline water that composes much of a planets hydrosphere. On Earth, an ocean is one of the major divisions of the World Ocean. These are, in descending order by area, the Pacific, Atlantic, Indian, Southern, the word sea is often used interchangeably with ocean in American English but, strictly speaking, a sea is a body of saline water partly or fully enclosed by land. The ocean contains 97% of Earths water, and oceanographers have stated that less than 5% of the World Ocean has been explored, the total volume is approximately 1.35 billion cubic kilometers with an average depth of nearly 3,700 meters. As the world ocean is the component of Earths hydrosphere, it is integral to all known life, forms part of the carbon cycle. The world ocean is the habitat of 230,000 known species, but because much of it is unexplored, the origin of Earths oceans remains unknown, oceans are thought to have formed in the Hadean period and may have been the impetus for the emergence of life. Extraterrestrial oceans may be composed of water or other elements and compounds, the only confirmed large stable bodies of extraterrestrial surface liquids are the lakes of Titan, although there is evidence for the existence of oceans elsewhere in the Solar System. Early in their histories, Mars and Venus are theorized to have had large water oceans. The Mars ocean hypothesis suggests that nearly a third of the surface of Mars was once covered by water, compounds such as salts and ammonia dissolved in water lower its freezing point so that water might exist in large quantities in extraterrestrial environments as brine or convecting ice. Unconfirmed oceans are speculated beneath the surface of many planets and natural satellites, notably. The Solar Systems giant planets are thought to have liquid atmospheric layers of yet to be confirmed compositions. Oceans may also exist on exoplanets and exomoons, including surface oceans of water within a circumstellar habitable zone. Ocean planets are a type of planet with a surface completely covered with liquid. The concept of Ōkeanós has an Indo-European connection, Greek Ōkeanós has been compared to the Vedic epithet ā-śáyāna-, predicated of the dragon Vṛtra-, who captured the cows/rivers. Related to this notion, the Okeanos is represented with a dragon-tail on some early Greek vases, though generally described as several separate oceans, these waters comprise one global, interconnected body of salt water sometimes referred to as the World Ocean or global ocean. This concept of a body of water with relatively free interchange among its parts is of fundamental importance to oceanography. The major oceanic divisions – listed below in descending order of area and volume – are defined in part by the continents, various archipelagos, Oceans are fringed by smaller, adjoining bodies of water such as seas, gulfs, bays, bights, and straits. The Mid-Oceanic Ridge of the World are connected and form the Ocean Ridge, the continuous mountain range is 65,000 km long, and the total length of the oceanic ridge system is 80,000 km long
This article incorporates public domain material from the Bureau of Land Management document: "Grassland Habitat Group" (PDF). Archived from the original (PDF) on 2008-07-24.
This article incorporates 
Media related to Alpine tundra at Wikimedia Commons