Gangotri Glacier

Gangotri
Gangotri
	Gomukh, terminus of the Gangotri glacier. The Bhagirathi peaks rise in the background.
Type	Valley glacier
Location	India
Coordinates	30°50′N 79°10′E / 30.833°N 79.167°E

Gangotri glacier (Sanskrit and Hindi: गंगोत्री) is located in Uttarkashi District, Uttarakhand, India in a region bordering Tibet. This glacier, one of the primary sources of the Ganges, has a volume of over 27 cubic kilometers.^[1] The glacier is about 30 kilometres (19 miles) long and 2 to 4 km (1 to 2 mi) wide. Around the glacier are the peaks of the Gangotri Group, including several peaks notable for extremely challenging climbing routes, such as Shivling, Thalay Sagar, Meru, and Bhagirathi III. It flows roughly northwest, originating in a cirque below Chaukhamba, the highest peak of the group.

The terminus of the Gangotri Glacier is said to resemble a cow's mouth, and the place is called Gomukh or Gaumukh (gou, cow + mukh, face). Gomukh, which is about 19 km (11.8 mi) from the town of Gangotri, is the precise source of the Bhagirathi river, an important tributary of the Ganges. Gomukh is situated near the base of Shivling; in between lies the Tapovan meadow.

The Gangotri glacier is a traditional Hindu pilgrimage site. Devout Hindus consider bathing in the icy waters near Gangotri town to be a holy ritual, and many made the trek to Gomukh, with a few continuing on to Tapovan. One needs to trek from Gangotri till Gaumukh, passing Devgadh, Chirbhasa, Bhojwasa en route. Currently accommodation is available only at Bhojwasa, although forest check posts are present at both Chirbhasa and Bhowasa. The 2013 North Indian Floods destroyed much of this trail, and access is now a little difficult beyond Chirbhasa due to trail deterioration and a 2 km wide rockfall site.

Geology

A small shrine at Gaumukh, Gangotri glacier.

It is a valley-type glacier, situated in the Uttarkashi district of Garhwal Himalaya, Uttarakhand and it flows to the NW direction. This glacier is bound between 30°43'22"–30°55'49" (lat.) and 79°4'41"–79°16'34" (long.), extending in height from 4120 to 7000 m.a.s.l. This area is situated north of the Main Central Thrust (MCT) and is made up of bedrocks of granites, garnet mica schist, quartz biotite schist, kyanite schist, augen gneiss and banded augen gneiss.^[2] The glacier is composed of a variety of depositional features such as talus cones, snow-avalanche fans, snow-bridges, and dead ice mounds, and erosional features like pyramidal and conical peaks, serrated ridge crests, glacial troughs, smooth rock walls and tails, waterfalls, rock basins, gullies and glacial lakes. All along the Gangotri glacier, several longitudinal and transverse crevasses are formed along which ice blocks have broken down. The ablation zone of the Gangotri glacier is covered by a thick pile of supraglacial moraines and is characterized by several ice sections, melting into pools of supraglacial lakes. Because of subsidence and the fast degenerating nature of the glacier, its centre is full of supraglacial lakes. In this part of higher Himalaya, glacial melt-water dominates the fluvial system.

The total ice cover is approximately 200 km² and has about 20 km³ of ice in volume.^[3]

Tributaries

This glacier has three main tributaries, namely Raktvarn (15.90 km), Chaturangi (including Kalindi bamak) (22.45 km) and Kirti (11.05 km) and more than 18 smaller tributary glaciers. The Raktvarn system contains 7 tributary glaciers; among them Thelu, Swetvarn, Nilambar and Pilapani are important. Similarly the Seeta, Suralaya and Vasuki are the major tributaries which make up the Chaturangi system, while the Kirti system is made up of only three tributary glaciers. Besides these three major tributary systems, some other tributary glaciers of this area drain directly into the Gangotri glacier; among them Swachand, Miandi, Sumeru and Ghanohim are important. Four other glaciers, Maitri, Meru, Bhrigupanth and Manda drain into the river Bhagirathi. The total glacierized area of the catchment is 258.56 km², out of which the Gangotri system comprises 109.03 km², followed by Chaturangi (72.91 km²), Raktvarn (45.34 km²) and Kirti (31.28 km²). The remaining four glaciers contain 29.41 km² of glacierized area; among them maximum contribution is Bhirgupanth glacier (14.95 km²).

Retreat

Retreat of Gangotri Glacier

NASA, in conjunction with scientists from United States Geological Survey (USGS) and the National Snow and Ice Data Center (NSIDC), is developing a global inventory of all the world's glaciers to help researchers track each glacier's history. According to them, the Gangotri glacier, currently 30.2 km long and between 0.5 and 2.5 km wide, is one of the largest in the Himalayas. This glacier has been constantly receding since measurements began in 1780. Data for 61 years (1936–96) showed the total recession of Gangotri glacier as 1147 m, with an average rate of 19 m per year.^[4] However over the last 25 years into the 21st century it has retreated more than 850 meters (34 meters per year),^[5] and 76 meters between 1996 and 1999 (25 meters per year)^[6]^[7]

Notes

^ Gyan Marwah. "Ganges - A River of No Return?". the-south-asian.com. Archived from the original on 16 September 2013. Retrieved 24 June 2007.
^ Metcalfe, R. P., Geol. Soc. London, 1993, 74, 495–509.
^ Vohra, C. P., in The Himalayas: Aspects of Change (eds Lall, J. S. and Moddie, A. D.), Oxford University Press, New Delhi, 1981, pp 138–151.
^ Ajay K. Naithani, H. C. Nainwal, K. K. Sati and C. Prasad: Geomorphological evidences of retreat of the Gangotri glacier and its characteristics. Current Science, 2001, Vol. 80, No. 1, 87-94. http://www.ias.ac.in/currsci/jan102001/87.pdf Archived 17 October 2020 at the Wayback Machine
^ Sharma, M. C. and Owen, L. A., J. Quat. Sci. Rev., 1996, 15, 335–365.
^ article at Earth Observatory driven by NASA Archived 31 December 2009 at the Wayback Machine, found below a sat image illustration dated 2001
^ Lal, P.; Vaka, D. S.; Rao, Y. S. (15 November 2018). "Mapping Surface Flow Velocities of Siachen and Gangotri Glaciers Using Terrasar-X and Sentinel-1A Data by Intensity Tracking". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences. IV-5: 325–329. doi:10.5194/isprs-annals-IV-5-325-2018.

References

Bali, R., Awasthi, D.D. and Tiwari, N.K.2003 Neotectonic control on the geomorphic evolution of the Gangotri Glacier Valley, Garhwal Himalaya, Gondwana Research, 2003, Vol, 6 (4) pp. 829–838.
Awasthi, D.D., Bali, R. and Tiwari, N.K. 2004. Relative dating by lichenometric and Schmidt Hammer techniques in the Gangotri glacier valley, Uttarkashi District, Uttaranchal. Spl. Pub. Pal. Soc. Ind no. 2 pp. 201– 206.
Awasthi, D.D., Bali, R. and Tiwari, N.K. 2004. Growth rate of Lichen Dimelaena Orina in the Gangotri Glacier valley, Uttarkashi District, Uttaranchal: Some Significant Observations Geol. Sur. Ind. Spl. Pub. No. 80.
Singh, Dhruv Sen 2004. Late Quaternary Morpho-Sedimentary Processes in the Gangotri Glacier Area, Garhwal Himalaya, India. Geol Surv India Spl. Pub. No.80, 2004: 97-103.
Singh, Dhruv Sen and Mishra. A. 2002. Gangotri Glacier System, Garhwal Himalaya: An analysis using GIS technique. Aspects of Geology and Environment of the Himalaya. Edited by Pant, C. C. and Sharma, A. Gyanodaya Prakashan, Nainital, India, pp 349–358.
Singh, Dhruv Sen and Mishra. A. 2002. Role of Tributary glaciers on landscape modification in the Gangotri Glacier area, Garhwal Himalaya, India. Current Science, 82 (5), 101-105. http://www.ias.ac.in/currsci/mar102002/567.pdf
Singh, Dhruv Sen and Mishra, A. 2001. Gangotri Glacier characteristics, retreat and processes of sedimentation in the Bhagirathi valley. Geological Survey of India Spl. Pub.No.65 (III), 17-20.
Lal, P.; Vaka, D. S.; Rao, Y. S. (15 November 2018). "Mapping Surface Flow Velocities of Siachen and Gangotri Glaciers Using Terrasar-X and Sentinel-1A Data by Intensity Tracking". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences. IV-5: 325–329. doi:10.5194/isprs-annals-IV-5-325-2018.

External links

Retreat of the Gangotri Glacier, an article from NASA's Earth Observatory
Gaumukh and Gangotri Art Photos
Save Gangotri, highlights localized ecological damage and conservation efforts in the region
Geomorphological evidences of retreat of the Gangotri glacier and its characteristics, A Study by Department of Geology, HNB Garhwal University
283 photos 1280x960 of trekking from Gangotri to Gaumukh. You can see the retreat of the Gangotri glacier on picture gomukh141.jpg

[gangotri-1] Gyan Marwah. "Ganges - A River of No Return?". the-south-asian.com. Archived from the original on 16 September 2013. Retrieved 24 June 2007.

[2] Metcalfe, R. P., Geol. Soc. London, 1993, 74, 495–509.

[3] Vohra, C. P., in The Himalayas: Aspects of Change (eds Lall, J. S. and Moddie, A. D.), Oxford University Press, New Delhi, 1981, pp 138–151.

[4] Ajay K. Naithani, H. C. Nainwal, K. K. Sati and C. Prasad: Geomorphological evidences of retreat of the Gangotri glacier and its characteristics. Current Science, 2001, Vol. 80, No. 1, 87-94. http://www.ias.ac.in/currsci/jan102001/87.pdf Archived 17 October 2020 at the Wayback Machine

[5] Sharma, M. C. and Owen, L. A., J. Quat. Sci. Rev., 1996, 15, 335–365.

[6] rticle at Earth Observatory driven by NASA Archived 31 December 2009 at the Wayback Machine, found below a sat image illustration dated 2001

[7] Lal, P.; Vaka, D. S.; Rao, Y. S. (15 November 2018). "Mapping Surface Flow Velocities of Siachen and Gangotri Glaciers Using Terrasar-X and Sentinel-1A Data by Intensity Tracking". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences. IV-5: 325–329. doi:10.5194/isprs-annals-IV-5-325-2018.

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