Himalayas

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"Himalaya" redirects here. For other uses, see Himalaya (disambiguation).
Himalayas
Everest North Face toward Base Camp Tibet Luca Galuzzi 2006 edit 1.jpg
The north face of Mount Everest as seen from the path to the base camp in Tibet, China.
Highest point
Peak Mount Everest (Nepal & China)
Elevation 8,848 m (29,029 ft)
Coordinates 27°59′17″N 86°55′31″E / 27.98806°N 86.92528°E / 27.98806; 86.92528
Dimensions
Length 2,400 km (1,500 mi)
Geography
Himalayas Map.png
The general location of the Himalayas mountain range.
Countries
Range coordinates 28°N 82°E / 28°N 82°E / 28; 82
NASA Landsat-7 imagery of Himalayas

The Himalayas, or Himalaya, (/ˌhɪməˈl.ə/ or /hɪˈmɑːləjə/; Sanskrit: हिमालय, hima (snow) + ālaya (dwelling), Sanskrit word literally meaning, "abode of the snow"[1]) is a mountain range in South Asia separating the plains of the Indian subcontinent from the Tibetan Plateau.

The Himalayan range is home to the planet's highest peaks, including the highest, Mount Everest. The Himalayas include over a hundred mountains exceeding 7,200 metres (23,600 ft) in elevation. By contrast, the highest peak outside Asia – Aconcagua, in the Andes – is 6,961 metres (22,838 ft) tall.[2] The Himalayas have profoundly shaped the cultures of South Asia. Many Himalayan peaks are sacred in both Buddhism and Hinduism.

Besides the Greater Himalayas of these high peaks there are parallel lower ranges. The first foothills, reaching about a thousand meters along the northern edge of the plains, are called the Sivalik Hills or Sub-Himalayan Range. Further north is a higher range reaching two to three thousand meters known as the Lower Himalayan or Himachal or Mahabharat Range.

The Himalayas abut or cross five countries: India, Nepal, Bhutan, China, and Pakistan, with the first three countries having sovereignty over most of the range.[3] The Himalayas are 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.

Three of the world's major rivers, the Indus, the Ganges and the Tsangpo-Brahmaputra, rise in the Himalayas. While the Indus, and the Tsangpo-Brahmaputra rise near Mount Kailash, the Ganges rises in the Indian state of Uttarkhand. Their combined drainage basin is home to some 600 million people.

Lifted by the collision of the Indian tectonic plate with the Eurasian Plate,[4] the Himalayan range runs, west-northwest to east-southeast, in an arc 2,400 kilometres (1,500 mi) long. Its western anchor, Nanga Parbat, lies just south of the northernmost bend of Indus river, its eastern anchor, Namcha Barwa, just west of the great bend of the Tsangpo river. The range varies in width from 400 kilometres (250 mi) in the west to 150 kilometres (93 mi) in the east.

Ecology[edit]

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 and snow at the highest elevations. 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 very high snow line supports a variety of distinct plant and animal communities. For example the extremes of high altitude (low atmospheric pressure) combined with extreme cold allow extremophile organisms to survive.[5]

The unique floral and faunal wealth of the Himalayas is undergoing structural and compositional changes due to climate change. The increase in temperature may shift 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 tree species, especially rhododendron, apple and Myrica esculenta. The highest known tree species in the Himalayas is Juniperus tibetica located at 4,900 metres (16,080 ft) in Southeastern Tibet.[6]

Geology[edit]

The 6,000 km plus journey of the India landmass (Indian Plate) before its collision with Asia (Eurasian Plate) about 40 to 50 million years ago[4]

The Himalaya are among the youngest mountain ranges on the planet and consist mostly of uplifted sedimentary and metamorphic rock. According to the modern theory of plate tectonics, 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 Arakan Yoma highlands in Myanmar and the Andaman and Nicobar Islands in the Bay of Bengal were also formed as a result of this collision.

During the Upper Cretaceous, about 70 million years ago, the north-moving Indo-Australian Plate was moving at about 15 cm per year. About 50 million years ago this fast moving Indo-Australian plate had completely closed the Tethys Ocean, the existence of which has been determined by sedimentary rocks settled on the ocean floor, and the volcanoes that fringed its edges. Since both plates were composed of low density continental crust, they were thrust faulted and folded into mountain ranges rather than subducting into the mantle along an oceanic trench.[4] An often-cited fact used to illustrate this process is that the summit of Mount Everest is made of marine limestone from this ancient ocean.[7]

Today, the Indo-Australian plate continues to be driven horizontally below the Tibetan plateau, which forces the plateau to continue to move upwards. The Indo-Australian plate is still moving at 67 mm per year, and over the next 10 million years it will travel about 1,500 km into Asia. About 20 mm per year of the India-Asia convergence is absorbed by thrusting along the Himalaya southern front. This leads to the Himalayas rising by about 5 mm per year, making them geologically active. The movement of the Indian plate into the Asian plate also makes this region seismically active, leading to earthquakes from time to time.

During the last ice age, there was a connected ice stream of glaciers between Kangchenjunga in the east and Nanga Parbat in the west.[8] In the west, the glaciers joined with the ice stream network in the Karakoram, and in the north, joined with the former Tibetan inland ice. To the south, outflow glaciers came to an end below an elevation of 1,000–2,000 metres (3,300–6,600 ft).[8][9] While the current valley glaciers of the Himalaya reach at most 20 to 32 kilometres (12 to 20 mi) in length, several of the main valley glaciers were 60 to 112 kilometres (37 to 70 mi) long during the ice age.[8] The glacier snowline (the altitude where accumulation and ablation of a glacier are balanced) was about 1,400–1,660 metres (4,590–5,450 ft) lower than it is today. Thus, the climate was at least 7.0 to 8.3 °C (12.6 to 14.9 °F) colder than it is today.[10]

Hydrology[edit]

Indus River
The Himalayan range at Yumesongdong in Sikkim, in the Yumthang River valley

The Himalayas have the third largest deposit of ice and snow in the world, after Antarctica and the Arctic.[11] The Himalayan range encompasses about 15,000 glaciers, which store about 12,000 km3 (3000 cubic miles) of fresh water.[12] Its glaciers include the Gangotri and Yamunotri (Uttarakhand) and Khumbu glaciers (Mount Everest region), and Zemu (Sikkim).

Owing to the mountains' latitude near the Tropic of Cancer, the permanent snow line is among the highest in the world at typically around 5,500 metres (18,000 ft).[13] In contrast, equatorial mountains in New Guinea, the Rwenzoris and Colombia have a snow line some 900 metres (2,950 ft) lower.[14] The higher regions of the Himalayas are snowbound throughout the year, in spite of their proximity to the tropics, and they form the sources of several large perennial rivers, most of which combine into two large river systems:

  • The western rivers combine into the Indus Basin, of which the Indus River is the largest. The Indus begins in Tibet at the confluence of Sengge and Gar rivers and flows southwest through India and then through Pakistan to the Arabian Sea. It is fed by the Jhelum, the Chenab, the Ravi, the Beas, and the Sutlej rivers, among others.
  • Most of the other Himalayan rivers drain the Ganges-Brahmaputra Basin. Its main rivers are the Ganges, the Brahmaputra and the Yamuna, as well as other tributaries. The Brahmaputra originates as the Yarlung Tsangpo River in western Tibet, and flows east through Tibet and west through the plains of Assam. The Ganges and the Brahmaputra meet in Bangladesh, and drain into the Bay of Bengal through the world's largest river delta,the Sunderbans.[15]

The easternmost Himalayan rivers feed the Ayeyarwady River, which originates in eastern Tibet and flows south through Myanmar to drain into the Andaman Sea.

The Salween, Mekong, Yangtze and Huang He (Yellow River) all originate from parts of the Tibetan plateau that are geologically distinct from the Himalaya mountains, and are therefore not considered true Himalayan rivers. Some geologists refer to all the rivers collectively as the circum-Himalayan rivers.[16] In recent years, scientists have monitored a notable increase in the rate of glacier retreat across the region as a result of global climate change.[17] For example, Glacial lakes have been forming rapidly on the surface of the debris-covered glaciers in the Bhutan Himalaya during the last few decades. Although the effect of this will not be known for many years, it potentially could mean disaster for the hundreds of millions of people who rely on the glaciers to feed the rivers of northern India during the dry seasons.[18] Some of the lakes present a danger of a glacial lake outburst flood. The Tsho Rolpa glacier lake in the Rolwaling Valley is rated as the most dangerous in Nepal.[19][20]

Lakes[edit]

A high Himalayan lake at an altitude of around 5,000 metres Sikkim, India

The Himalayan region is dotted with hundreds of lakes. Most lakes are found at altitudes of less than 5,000 m, with the size of the lakes diminishing with altitude. Tilicho Lake in Nepal in the Annapurna massif is one of the highest lakes in the world. Pangong Tso, which is spread across the border between India and China, and Yamdrok Tso, located in central Tibet, are amongst the largest with surface areas of 700 km², and 638 km², respectively. Other notable lakes include Gurudongmar Lake, in North Sikkim, and Lake Tsongmo, near the Indo-China border in Sikkim.

The mountain lakes are known to geographers as tarns if they are caused by glacial activity. Tarns are found mostly in the upper reaches of the Himalaya, above 5,500 metres.[21]

Impact on climate[edit]

The Himalayas have a profound effect on the climate of the Indian subcontinent and the Tibetan plateau. They prevent frigid, dry Arctic winds blowing south into the subcontinent, which keeps South Asia much warmer than corresponding temperate regions in the other continents. It also forms a barrier for the monsoon winds, keeping them from traveling northwards, and causing heavy rainfall in the Terai region. The Himalayas are also believed to play an important part in the formation of Central Asian deserts, such as the Taklamakan and Gobi.[22]

Religion[edit]

The Taktsang Monastery, also known as the "Tiger's Nest"
Pass in Ladakh with the typical Buddhist prayer flags and chorten
The Himalayas between India and Tibet illustrated in the Jami' al-tawarikh.

In Hinduism, the Himalayas have been personified as the god Himavat, father of Ganga and Parvati.[23]

Several places in the Himalayas are of religious significance in Hinduism, Jainism, Sikhism, and Buddhism. A notable example of a religious site is Paro Taktsang, where Padmasambhava is said to have founded Buddhism in Bhutan.[24]

A number of Tibetan Buddhist sites are situated in the Himalayas, including the residence of the Dalai Lama. There were over 6,000 monasteries in Tibet.[25] The Tibetan Muslims had their own mosques in Lhasa and Shigatse.[26]

Gallery[edit]

Panoramic view of Langtang Range

See also[edit]

References[edit]

  1. ^ "Definition of Himalayas". Oxford Dictionaries Online. Retrieved 9 May 2011. 
  2. ^ Yang, Qinye; Zheng, Du (2004). Himalayan Mountain System. ISBN 9787508506654. Retrieved 7 August 2007. 
  3. ^ Bishop, Barry. "Himalayas (mountains, Asia)". Encyclopaedia Britannica. Retrieved 1 October 2012. 
  4. ^ a b c The Himalayas: Two continents collide, USGS
  5. ^ Hogan, C. Michael (2010). "Archaea". In Monosson, E.; Cleveland, C. Encyclopedia of Earth. Washington DC: National Council for Science and the Environment. 
  6. ^ Miehe, Georg; Miehe, Sabine; Vogel, Jonas; Co, Sonam; Duo, La (May 2007). "Highest Treeline in the Northern Hemisphere Found in Southern Tibet". Mountain Research and Development 27 (2): 169–173. doi:10.1659/mrd.0792. Archived from the original on 6 June 2013. 
  7. ^ A site which uses this dramatic fact first used in illustration of "deep time" in John McPhee's book Basin and Range
  8. ^ a b c Kuhle, M. (2011). "The High Glacial (Last Ice Age and Last Glacial Maximum) Ice Cover of High and Central Asia, with a Critical Review of Some Recent OSL and TCN Dates". In Ehlers, J.; Gibbard, P.L.; Hughes, P.D. Quaternary Glaciation – Extent and Chronology, A Closer Look. Amsterdam: Elsevier BV. pp. 943–965.  (glacier maps downloadable)
  9. ^ Kuhle, M (1987). "Subtropical mountain- and highland-glaciation as ice age triggers and the waning of the glacial periods in the Pleistocene". GeoJournal 14 (4): 393–421. doi:10.1007/BF02602717. 
  10. ^ Kuhle, M. (2005). The maximum Ice Age (Würmian, Last Ice Age, LGM) glaciation of the Himalaya – a glaciogeomorphological investigation of glacier trim-lines, ice thicknesses and lowest former ice margin positions in the Mt. Everest-Makalu-Cho Oyu massifs (Khumbu- and Khumbakarna Himal) including informations on late-glacial-, neoglacial-, and historical glacier stages, their snow-line depressions and ages. "Tibet and High Asia (VII): Glaciogeomorphology and Former Glaciation in the Himalaya and Karakorum". GeoJournal (Dordrecht: Kluwer) 62 (3–4): 193–650. doi:10.1007/s10708-005-2338-6. 
  11. ^ "The Himalayas". Nature on PBS. Retrieved 21 January 2014. 
  12. ^ "the Himalayan Glaciers". Fourth assessment report on climate change. IPPC. 2007. Retrieved 22 January 2014. 
  13. ^ Shi, Yafeng; Xie, Zizhu; Zheng, Benxing; Li, Qichun (1978). "Distribution, Feature and Variations of Glaciers in China". World Glacier Inventory (Riederalp Workshop). 
  14. ^ Henderson-Sellers, Ann; McGuffie, Kendal. The Future of the World's Climate: A Modelling Perspective. pp. 199–201. ISBN 9780123869173. 
  15. ^ "Sunderbans the world's largest delta". gits4u.com. 
  16. ^ Gaillardet, J; Métivier, F.; Lemarchand, D.; Dupré, B.; Allègre, C. J.; Li, W.; Zhao, J. (2003). "Geochemistry of the Suspended Sediments of Circum-Himalayan Rivers and Weathering Budgets over the Last 50 Myrs" (PDF). Geophysical Research Abstracts 5 (13617): 13617. Bibcode:2003EAEJA....13617G. Retrieved 4 November 2006. 
  17. ^ "Vanishing Himalayan Glaciers Threaten a Billion". Planet Ark. 5 June 2007. Retrieved 17 April 2009. 
  18. ^ "Glaciers melting at alarming speed". People's Daily Online. 24 July 2007. Retrieved 17 April 2009. 
  19. ^ Photograph of Tsho Rolpa
  20. ^ Tsho Rolpa
  21. ^ Drews, Carl. "Highest Lake in the World". Retrieved 14 November 2010. 
  22. ^ Devitt, Terry (3 May 2001). "Climate shift linked to rise of Himalayas, Tibetan Plateau". University of Wisconsin–Madison News. Retrieved 1 November 2011. 
  23. ^ Dallapiccola, Anna (2002). Dictionary of Hindu Lore and Legend. ISBN 0-500-51088-1. 
  24. ^ Pommaret, Francoise (2006). Bhutan Himlayan Mountains Kingdom (5th ed.). Odyssey Books and Guides. pp. 136–7. ISBN 978-9622178106. 
  25. ^ "Tibetan monks: A controlled life". BBC News. 20 March 2008. 
  26. ^ "Mosques in Lhasa, Tibet". People's Daily Online. 27 October 2005. 

Further reading[edit]

  • Aitken, Bill, Footloose in the Himalaya, Delhi, Permanent Black, 2003. ISBN 81-7824-052-1
  • Berreman, Gerald Duane, Hindus of the Himalayas: Ethnography and Change, 2nd rev. ed., Delhi, Oxford University Press, 1997.
  • Bisht, Ramesh Chandra, Encyclopedia of the Himalayas, New Delhi, Mittal Publications, c2008.
  • Everest, the IMAX movie (1998). ISBN 0-7888-1493-1
  • Fisher, James F., Sherpas: Reflections on Change in Himalayan Nepal, 1990. Berkeley, University of California Press, 1990. ISBN 0-520-06941-2
  • Gansser, Augusto, Gruschke, Andreas, Olschak, Blanche C., Himalayas. Growing Mountains, Living Myths, Migrating Peoples, New York, Oxford: Facts On File, 1987. ISBN 0-8160-1994-0 and New Delhi: Bookwise, 1987.
  • Gupta, Raj Kumar, Bibliography of the Himalayas, Gurgaon, Indian Documentation Service, 1981
  • Hunt, John, Ascent of Everest, London, Hodder & Stoughton, 1956. ISBN 0-89886-361-9
  • Isserman, Maurice and Weaver, Stewart, Fallen Giants: The History of Himalayan Mountaineering from the Age of Empire to the Age of Extremes. Yale University Press, 2008. ISBN 978-0-300-11501-7
  • Ives, Jack D. and Messerli, Bruno, The Himalayan Dilemma: Reconciling Development and Conservation. London / New York, Routledge, 1989. ISBN 0-415-01157-4
  • Lall, J.S. (ed.) in association with Moddie, A.D., The Himalaya, Aspects of Change. Delhi, Oxford University Press, 1981. ISBN 0-19-561254-X
  • Nandy, S.N., Dhyani, P.P. and Samal, P.K., Resource Information Database of the Indian Himalaya, Almora, GBPIHED, 2006.
  • Palin, Michael, Himalaya, London, Weidenfeld & Nicolson Illustrated, 2004. ISBN 0-297-84371-0
  • Swami Sundaranand, Himalaya: Through the Lens of a Sadhu. Published by Tapovan Kuti Prakashan (August 2001). ISBN 81-901326-0-1
  • Swami Tapovan Maharaj, Wanderings in the Himalayas, English Edition, Madras, Chinmaya Publication Trust, 1960. Translated by T.N. Kesava Pillai.
  • Tilman, H. W., Mount Everest, 1938, Cambridge University Press, 1948.
  • 'The Mighty Himalaya: A Fragile Heritage,’ National Geographic, 174:624–631 (November 1988).
  • Turner, Bethan, et al. Seismicity of the Earth 1900–2010: Himalaya and Vicinity. Denver, United States Geological Survey, 2013.

External links[edit]