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60-543: The Juneau Icefield is an ice field located just north of Juneau , Alaska , continuing north through the border with British Columbia , extending through an area of 3,900 square kilometres (1,500 sq mi) in the Coast Range ranging 140 km (87 mi) north to south and 75 km (47 mi) east to west. The icefield is the source of many glaciers , including the Mendenhall Glacier and

120-428: A few birds, e.g. the sandgrouse, lark, stonechat, sparrow, crane, Mongolian ground jay ( Podoces hendersoni ), horned lark ( Eremophila alpestris ), and crested lark ( Galerida cristata ). The structure here is that of the mighty T'ien Shan , or Heavenly Mountains, running from west to east. It divides the northern one-third of Sinkiang from the southern two-thirds. On the northern side, rivers formed from

180-543: A high proportion of woody, fragrant plants. Gobi mutton is the most aromatic in the world. The Yulduz valley or valley of the Haidag-gol ( 43°N 83°E  /  43°N 83°E  / 43; 83 – 43°N 86°E  /  43°N 86°E  / 43; 86 ) is a mini desert enclosed by two prominent members of the Shanashen Trahen Osh mountain range, namely the chucis and

240-502: A large calving front. By 1963, the glacier had advanced 5.6 km (3.5 mi). In 1948, the Taku Fjord had been completely filled in with glacial sediment and the glacier no longer calved. From 1948–1986, the glacier had a positive glacier mass balance driving the advance. From 1987–2009, the glacier has had a slightly negative mass balance, not enough to end the advance, but if it continues will soon slow it. Notable peaks on

300-462: A source of cashmere wool . Large copper deposits are being mined by Rio Tinto Group . The mine was and remains controversial. There was significant opposition in Mongolia's parliament to the terms under which the mine will proceed, and some are calling for the terms to be renegotiated. Specifically, the contention revolves primarily around the question of whether negotiations were fair (Rio Tinto

360-624: A warm 27 °C (81 °F). Most of the precipitation falls during the summer. Although the southeast monsoons reach the southeast parts of the Gobi, the area throughout this region is generally characterized by extreme dryness, especially during the winter, when the Siberian anticyclone is at its strongest. The southern and central parts of the Gobi Desert have variable plant growth due to this monsoon activity. The more northern areas of

420-437: Is a Chinese government tree-planting project begun in 1978 and set to continue through 2050. The goal of the program is to reverse desertification by planting aspen and other fast-growing trees on some 36.5 million hectares across some 551 counties in 12 provinces of northern China. The Gobi, broadly defined, can be divided into five distinct dry ecoregions , based on variations in climate and topography: The surface

480-611: Is absolutely sterile, and its northern foot rests upon a narrow belt of barren sand, which leads down to the depressions mentioned above. The Kuruk-tagh is the greatly disintegrated, denuded and wasted relic of a mountain range which used to be of incomparably greater magnitude. In the west, between Lake Bosten and the Tarim , it consists of two, possibly of three, principal ranges, which, although broken in continuity, run generally parallel to one another, and embrace between them numerous minor chains of heights. These minor ranges, together with

540-916: Is also distinguishable from an ice cap because it does not have a dome-like form. There are several ice fields in the Himalayas and Altay Mountains (the border range between the Central Asian Republics and China ). One unexpected ice field is located in Yolyn Am , a mountain valley located in the northern end of the Gobi Desert . There are no ice fields in Australia . New Zealand has Reference: The only large ice fields in mainland Europe are in Norway (e.g., Dovre and Jotunheimen ). There are several dozen small ice fields in

600-524: Is also located on a plateau roughly 910–1,520 m (2,990–4,990 ft) above sea level, which contributes to its low temperatures. An average of about 194 mm (7.6 in) of rain falls annually in the Gobi. Additional moisture reaches parts of the Gobi in winter as snow is blown by the wind from the Siberian Steppes. These winds may cause the Gobi to reach −40 °C (−40 °F) in winter to 45 °C (113 °F) in summer. However,

660-408: Is confined to these same areas, is of the scantiest and is mainly confined to bushes of saxaul (Haloxylon) , anabasis , reeds (kamish), tamarisks , poplars , and Ephedra . There is little information about early habitation of the Gobi desert. Lisa Janz has proposed a system of nomenclature for early Gobi desert habitation. They are Oasis I, Oasis II, Oasis III. Oasis I is equivalent to

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720-591: Is crisscrossed by several trade routes, some of which have been in use for thousands of years. Among the most important are those from Kalgan (at the Great Wall) to Ulaanbaatar (960 km (597 mi)); from Jiuquan (in Gansu ) to Hami 670 km (416 mi); from Hami to Beijing (2,000 km (1,243 mi)); from Hohhot to Hami and Barkul; and from Lanzhou (in Gansu) to Hami. The southwestern portion of

780-627: Is extremely diversified, although there are no great differences in vertical elevation. Between Ulaanbaatar ( 48°00′N 107°00′E  /  48.000°N 107.000°E  / 48.000; 107.000 ) and the small lake of Iren-dubasu-nor ( 43°45′N 111°50′E  /  43.750°N 111.833°E  / 43.750; 111.833 ), the surface is greatly eroded. Broad flat depressions and basins are separated by groups of flat-topped mountains of relatively low elevation 150 to 180 m (490 to 590 ft), through which archaic rocks crop out as crags and isolated rugged masses. The floors of

840-670: Is far better resourced) and whether Rio Tinto will pay adequate taxes on the revenues it derives from the mine (an agreement was reached whereby the operation will be exempt from windfall tax ). The Gobi Desert is expanding through desertification , most rapidly on the southern edge into China, which is seeing 3,600 km (1,390 sq mi) of grassland overtaken every year. Dust storms increased in frequency between 1996 and 2016, causing further damage to China's agriculture economy. However, in some areas desertification has been slowed or reversed. The northern and eastern boundaries between desert and grassland are constantly changing. This

900-693: Is fringed by a string of deep depressions, ranging from Lukchun (130 m (427 ft) below sea level) to Hami (850 m (2,789 ft) above sea-level). To the south of the Kuruk-tagh lie the desert of Lop Nur , the Kum-tagh desert, and the valley of the Bulunzir-gol . To this great swelling, which arches up between the two border-ranges of the Chol-tagh and Kuruk-tagh, the Mongols give

960-501: Is mostly due to the climate conditions before the growing season, which influence the rate of evapotranspiration and subsequent plant growth. The expansion of the Gobi is attributed mostly to human activities, locally driven by deforestation , overgrazing , and depletion of water resources, as well as to climate change . China has tried various plans to slow the expansion of the desert, which have met with some success. The Three-North Shelter Forest Program (or "Green Great Wall")

1020-469: Is the world's second largest contiguous extrapolar ice field. At about 16,800 square kilometers, it is second only to southeastern Alaska's approximately 25,000 square kilometer Kluane / Wrangell–St. Elias / Glacier Bay / Tatshenshini-Alsek Ice Field . Another notable icefield is Campo de Hielo Norte ( Northern Patagonian Ice Field ), which is located entirely in Chile ; and a third smaller icefield, known as

1080-732: Is widest in the west, along the line joining the Lake Bosten and the Lop Nor (87°–89° east). Its area is approximately 1,295,000 square kilometres (500,000 sq mi). Gobi includes the long stretch of desert extending from the foot of the Pamirs (77° east) to the Greater Khingan Mountains, 116–118° east, on the border of Manchuria ; and from the foothills of the Altay, Sayan , and Yablonoi mountain ranges on

1140-1037: The Alps and tiny remnants of permanent ice in Sweden , the Apennines , the Pyrenees and the Balkans . Since the disappearance of the last remaining ice field in Andalucía , with the disappearance of the Corral del Veleta glacier in 1913, the southernmost surviving permanent ice field in continental Europe is Snezhnika in Bulgaria . Beyond the mainland of continental Europe, there are substantial ice fields in Iceland , Svalbard and Franz-Josef Land and smaller surviving ice fields on Jan Mayen and Novaya Zemlya . One of

1200-789: The Coast Mountains , Alaska Range , and Chugach Mountains of Alaska , British Columbia , and the Yukon Territory . The 6,500 km Stikine Icecap (located between the Stikine and Taku Rivers ) and the 2,500 km Juneau Icefield (located between Lynn Canal and the Taku River ) both straddle the British Columbian-Alaskan border. Farther north, the Kluane Icecap — which feeds

1260-603: The Mesolithic from 13500 cal BP to 8000 cal BP. During this time people began using oases . It is characterized by: Oasis II is equivalent to the Neolithic from 8000 cal BP to 5000 cal BP. People used the oases extensively. It was characterized by: Starting around 8000 cal BP there was a warm wet phase in the Gobi desert. By 7500 cal BP lake levels in the Western Gobi reached their peak. Around this time there

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1320-702: The Nemegt Basin in the northwestern part of the Gobi Desert (in Mongolia), which is noted for its fossil treasures, including early mammals , dinosaur eggs , and prehistoric stone implements , some 100,000 years old. Despite the harsh conditions, these deserts and the surrounding regions sustain many animal species. Some are even unique, including black-tailed gazelles , marbled polecats , wild Bactrian camels , Mongolian wild ass and sandplovers . They are occasionally visited by snow leopards , Gobi bears , and wolves . Lizards are especially well-adapted to

1380-679: The Sargent Icefield and the Harding Icefield . Throughout the Alaska Range there also large icefields (including one surrounding Denali ) which are mostly unnamed. In South America there are three main ice fields. The main ice field, known as Campo de Hielo Sur ( Southern Patagonian Ice Field ) is located at the Southern Patagonic Andes , and it is shared between Chile and Argentina . It

1440-496: The Taku Glacier . The icefield is home to over 40 large valley glaciers and 100 smaller ones. The Icefield serves as a tourist attraction with many travellers flown in by helicopter for quick walks on the 240-to-1,400-metre (790 to 4,590 ft) deep ice and the massive, awe-inspiring moist crevasses . The icefield, like many of its glaciers, reached its maximum glaciation point around 1700 and has been in retreat since. Much of

1500-531: The climate of the Gobi is one of great extremes, with rapid changes of temperature of as much as 35 °C (63 °F) in 24-hour spans. In southern Mongolia, the temperature has been recorded as low as −32.8 °C (−27.0 °F). In contrast, in Alxa , Inner Mongolia, it rises as high as 37 °C (99 °F) in July. Average winter minimums are a frigid −21 °C (−6 °F), while summertime maximums are

1560-536: The Ghashiun-Gobi and the Kuruk-tagh is determined by the aforementioned arrangements of the latitudinal valleys. Most of the principal streams, instead of flowing straight down these valleys, cross them diagonally and only turn west after they have cut their way through one or more of the transverse barrier ranges. To the highest range on the great swelling Grigory Grum-Grshimailo gives the name of Tuge-tau , its altitude being 2,700 m (8,858 ft) above

1620-710: The Gobi (known also as the Xitao or the "Little Gobi") encompasses the distance between the great northern loop of the Yellow River to the east, the Ejin River to the west, and the Qilian Mountains and narrow rocky chain of Longshou, 3,200 to 3,500 m (10,500 to 11,500 ft) in altitude, to the southwest. The Ordos Desert , which covers the northeastern portion of the Ordos Plateau (also near

1680-514: The Gobi are very cold and dry, making it unable to support much plant growth; this cold and dry weather is attributed to Siberian-Mongolian high pressure cells. Hence, the icy dust and snowstorms of spring and early summer plus early January (winter). The Gobi Desert is the source of many important fossil finds, including the first dinosaur eggs , twenty-six of which, averaging 23 centimetres (9 in) in length, were uncovered in 1923. Archeologists and paleontologists have done excavations in

1740-408: The Gobi, including Gobi Gurvansaikhan National Park , Great Gobi A and Great Gobi B Strictly Protected Area . The area is vulnerable to trampling by livestock and off-road vehicles (effects from human intervention are greater in the eastern Gobi Desert, where rainfall is heavier and may sustain livestock). In Mongolia, grasslands have been degraded by goats, which are raised by nomadic herders as

1800-532: The Han-gai ( Obruchev 's Gobi formation) which are characteristic of the southern parts of eastern Mongolia, are absent here or occur only in one locality, near the Shara-muren river. They are greatly intersected by gullies or dry watercourses. Water is scarce, with no streams, no lakes, no wells, and precipitation falls seldom. The prevailing winds blow from the west and northwest, and the pall of dust overhangs

1860-520: The Ice Fields of the Darwin Range, which is located on the western ( Chilean ) portion of Tierra del Fuego proper . Gobi Desert The Gobi Desert ( Mongolian : Говь , ᠭᠣᠪᠢ , / ˈ ɡ oʊ b i / ; Chinese : 戈壁 ; pinyin : gēbì ) is a large, cold desert and grassland region located in northern China and southern Mongolia . It is the sixth largest desert in

Juneau Icefield - Misplaced Pages Continue

1920-535: The Juneau Icefield are Devils Paw , Nelles Peak , Emperor Peak , The Snow Towers , Taku Towers , Camp 15 Peak , and the Mendenhall Towers . 58°36′N 134°30′W  /  58.600°N 134.500°W  / 58.600; -134.500 Ice field Ice fields are formed by a large accumulation of snow which, through years of compression and freezing, turns into ice. Because of

1980-522: The Lake Bosten, though parted from it by the drift-sand desert of Ak-bel-kum (White Pass Sands), has at first a west-northwest to east-southeast strike, but it gradually curves round like a scimitar towards the east-northeast and at the same time gradually decreases in elevation. At 91° east, where the principal range of the Kuruk-tagh system wheels to the east-northeast, four of its subsidiary ranges terminate, or rather die away somewhat suddenly, on

2040-554: The brink of a long narrow depression (in which Sven Hedin sees a northeast bay of the former great Central Asian lake of Lop-nor), having over against them the écheloned terminals of similar subordinate ranges of the Pe-shan (Boy-san) system (see below). The Kuruk-tagh is throughout a relatively low, but almost completely barren range, being entirely destitute of animal life, save for hares, antelopes and wild camels, which frequent its few small, widely scattered oases. The vegetation, which

2100-428: The central parts, until the bordering mountains are reached, trees and shrubs are utterly absent. Clay and sand are the predominant formations; the watercourses, especially in the north, being frequently excavated 2 to 3 m (6 ft 7 in to 9 ft 10 in) deep. In many places in the flat, dry valleys or depressions farther south, beds of loess , 5 to 6 m (16 to 20 ft) thick, are exposed. West of

2160-468: The climate of the Gobi Desert, with approximately 30 species distributed across its southern Mongolian border. The most common vegetation in the Gobi desert is shrubs adapted to drought. These shrubs included gray sparrow's saltwort ( Salsola passerina ), gray sagebrush , and low grasses such as needle grass and bridlegrass . Due to livestock grazing, the amount of shrubs in the desert has decreased. Several large nature reserves have been established in

2220-541: The country as in the Taklamakan and the desert of Lop . Characteristic of the flora are wild garlic, Kalidium gracile , wormwood , saxaul , Nitraria schoberi , Caragana , Ephedra , saltwort and the grass Lasiagrostis splendens . The taana wild onion Allium polyrrhizum is the main browse eaten by many herd animals, and Mongolians claim that this is essential in producing the proper, hazelnut-like notes of camel airag (fermented milk). The vast desert

2280-437: The depressions lie mostly between 900 and 1,000 m (3,000 and 3,300 ft) above sea-level. Further south, between Iren-dutiasu-nor and the Yellow River , comes a region of broad tablelands alternating with flat plains, the latter ranging at altitudes of 1000–1100 m and the former at 1,070 to 1,200 m (3,510 to 3,940 ft). The slopes of the plateaus are more or less steep and are sometimes penetrated by "bays" of

2340-829: The foot of the mountains, with barren shingle. Although on the whole a level country with a general altitude of 1,000 to 1,500 m (3,300 to 4,900 ft), this section, like most other parts of the Gobi, is crowned by a network of hills and broken ranges of at least 300 m in elevation. The vegetation is confined to a few varieties of bushes and a dozen kinds of grasses and herbs, the most conspicuous being saxaul ( Haloxylon ammondendron ) and Agriophyllum gobicum . The others include prickly convolvulus , field wormwood ( Artemisia campestris ), acacia , Inula ammophila , Sophora flavescens , Convolvulus ammanii , Peganum and Astragalus species, but all dwarfed, deformed and starved. The fauna consists of little but antelope, wolf, fox, hare, hedgehog, marten, numerous lizards and

2400-470: The great northern loop of the Yellow River) is part of this ecoregion within the middle basin of three great depressions into which Potanin divides the Gobi. "Topographically," says Nikolai Przhevalsky , "it is a perfectly level plain, which in all probability once formed the bed of a huge lake or inland sea." He concludes this based on the level area of the region as a whole, the hard saline clay and

2460-842: The icefield is contained within the Tongass National Forest . Since 1948, the Juneau Icefield Research Program has monitored glaciers of the Juneau Icefield. On the west side of the icefield, from 1946-2009, the terminus of the Mendenhall Glacier has retreated over 700 metres (0.43 mi). Eight kilometers to the north, the Herbert Glacier has retreated 540 m (0.34 mi), while Eagle Glacier retreated 700 m (0.43 mi), Gilkey Glacier 3,500 m (2.2 mi) and Llewellyn Glacier 2,800 m (1.7 mi). On

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2520-757: The immense Malaspina and Hubbard Glaciers as well as the Bagley Icefield — sits upon the British Columbia-Yukon Territory-Alaska border and surrounds most of the Saint Elias Mountains as well as both Mount Saint Elias and Mount Logan ; it extends as far west as the Copper River . There are also large ice fields located in the Kenai Peninsula - Chugach Mountains area, such as

2580-533: The increasing aridity between 3500 cal BP and 3000 cal BP there was a decline in human habitation in the Gobi desert. Prehistoric petroglyphs have been found in Southern Mongolia in 1997. The Gobi had a long history of human habitation, mostly by nomadic peoples. The name of Gobi means desert in Mongolian. The region was inhabited mostly by Mongols , Uyghurs , and Kazakhs . The Gobi Desert as

2640-426: The kracenard pine rallies, running perpendicular and far from one another. As they proceed south, they transcend and transpose, sweeping back on east and west respectively, with Lake Bosten in between. These two ranges mark the northern and the southern edges respectively of a great swelling, which extends eastward for nearly twenty degrees of longitude. On its northern side, the Chol-tagh descends steeply, and its foot

2700-521: The level of the sea and some 1,200 m (3,937 ft) above the crown of the swelling itself. This range he considers to belong to the Choltagh system, whereas Sven Hedin would assign it to the Kuruk-tagh. This last, which is pretty certainly identical with the range of Kharateken-ula (also known as the Kyzyl-sanghir , Sinir , and Singher Mountains ), that overlooks the southern shore of

2760-472: The lowlands. As the border-range of the Hyangan is approached, the country steadily rises up to 1,370 m (4,490 ft) and then to 1,630 m (5,350 ft). Here small lakes frequently fill the depressions, though the water in them is generally salty or brackish. Both here and for 320 km (199 mi) south of Ulaanbaatar, streams are frequent and grass grows more or less abundantly. Through all

2820-614: The more celebrated North American ice fields is the Columbia Icefield located in the Rocky Mountains between Jasper and Banff , Alberta . Easy access by road contributes to the status of this ice field as one of the most visited in North America, although it is actually a comparatively small ice field within the huge and largely ice-free American Cordillera . Many particularly expansive ice fields lie in

2880-439: The name of Ghashuun-Gobi or "Salt Desert". It is some 130 to 160 km (81 to 99 mi) across from north to south, and is traversed by a number of minor parallel ranges, ridges and chains of hills. Down its middle runs a broad stony valley, 40 to 80 km (25 to 50 mi) wide, at an elevation of 900 to 1,370 m (2,950 to 4,490 ft). The Chol-tagh, which reaches an average altitude of 1,800 m (5,900 ft),

2940-703: The north to the Kunlun , Altyn-Tagh , and Qilian mountain ranges, which form the northern edges of the Tibetan Plateau , on the south. A relatively large area on the east side of the Greater Khingan range, between the upper waters of the Songhua (Sungari) and the upper waters of the Liao-ho, is reckoned to belong to the Gobi by conventional usage. Some geographers and ecologists prefer to regard

3000-410: The principal ranges, divide the region into a series of long; narrow valleys, mostly parallel to one another and to the enclosing mountain chains, which descend like terraced steps, on the one side towards the depression of Lukchun and on the other towards the desert of Lop. In many cases these latitudinal valleys are barred transversely by ridges or spurs, generally elevations en masse of the bottom of

3060-399: The ranges from 200 to 500 m (660 to 1,640 ft) higher, though in a few cases they reach altitudes of 2,400 m (7,900 ft). The elevations do not form continuous chains, but make up a congeries of short ridges and groups rising from a common base and intersected by a labyrinth of ravines, gullies, glens, and basins. But the tablelands , built up of the horizontal red deposits of

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3120-432: The route from Ulaanbaatar to Kalgan , the country presents approximately the same general features, except that the mountains are not so irregularly scattered in groups but have more strongly defined strikes, mostly east to west, west-north-west to east-south-east, and west-south-west to east-north-east. The altitudes are higher, those of the lowlands ranging from 1,000 to 1,700 m (3,300 to 5,600 ft), and those of

3180-479: The sand-strewn surface and, lastly, the salt lakes which occupy its lowest parts. For hundreds of kilometers, nothing can be seen but bare sands; in some places, they continue so far without a break that the Mongols call them Tengger (i.e. sky). These vast expanses are absolutely waterless, nor do any oases relieve the unbroken stretches of yellow sand, which alternate with equally vast areas of saline clay or, nearer

3240-594: The snow and glaciers of the high mountains break through barren foothill ranges and flow out into an immense, hollow plain. Here the rivers begin to straggle and fan out, and form great marshes with dense reed-beds. Westerners call this terrain the Dzungarian desert. The Chinese also call it a desert, but the Mongols call it a 'gobi'—that is, a land of thin herbage, more suitable for camels than for cows, but capable also, if herds are kept small and moved frequently, of sustaining horses, sheep, and goats. The herbage comprises

3300-752: The south side of the icefield, the Norris Glacier retreated 1,740 m (1.08 mi), the East Twin Glacier 1,100 m (0.68 mi), the West Twin Glacier 570 m (0.35 mi) with only the Taku Glacier advancing. Surveys reveal the Taku as one of the deepest glaciers of the sub-temperate icefields surveyed at nearly 1,370 metres (4,490 ft) thick. This glacier was advancing in 1890 when viewed by John Muir and had

3360-434: The susceptibility of ice to gravity, ice fields usually form over large areas that are basins or atop plateaus, thus allowing a continuum of ice to form over the landscape uninterrupted by glacial channels. Glaciers often form on the edges of ice fields, serving as gravity-propelled drains off the ice field which is in turn replenished by snowfall. While an ice cap is not constrained by topography, an ice field is. An ice field

3420-399: The valley. Where such elevations exist, there is generally found, on the east side of the transverse ridge, a cauldron-shaped depression, which some time or other has been the bottom of a former lake, but is now nearly a dry salt-basin. The surface configuration is in fact markedly similar to that which occurs in the inter-mount latitudinal valleys of the Kunlun Mountains . The hydrography of

3480-426: The western area of the Gobi region (as defined above): the basin of the Tarim in Xinjiang and the desert basin of Lop Nor and Hami ( Kumul ), as forming a separate and independent desert, called the Taklamakan Desert . Much of the Gobi is not sandy, instead resembling exposed bare rock. The Gobi is overall a cold desert, with frost and occasionally snow occurring on its dunes . Besides being quite far north, it

3540-399: The world . The name of the desert comes from the Mongolian word gobi , used to refer to all of the waterless regions in the Mongolian Plateau ; in Chinese, gobi is used to refer to rocky, semi-deserts such as the Gobi itself rather than sandy deserts. The Gobi measures 1,600 km (1,000 mi) from southwest to northeast and 800 km (500 mi) from north to south. The desert

3600-439: Was meadow steppe vegetation around lakes. In Ulaan Nuur there may have been shrubby riparian woodlands. Oasis III is equivalent to the Bronze Age from 5000 cal BP to 3000 cal BP. It is characterized by: Bronze Age herder burials have been found in the Gobi desert, as well as Karasuk bronze knives, and Mongolian deer stones . Between 5000 cal BP and 4500 cal BP there was a period of desertification . Due to

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