Baltoro Glacier

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Baltoro Glacier
Aerial view of the Baltoro Glacier

Aerial view of the Baltoro Glacier

location Gilgit-Baltistan ( Pakistan )
Mountains Karakoram
Type Valley glacier
length 62 km
surface 524 km²
Exposure West from Concordiaplatz
Altitude range 6000  m  -  3400  m
Tilt ⌀ 2.2 ° (4%)
width ⌀ 2.1 km; Max. 3.1 km (at camp Gore I )
Ice thickness ⌀ 225 m
Coordinates 35 ° 44 '  N , 76 ° 32'  E Coordinates: 35 ° 44 '  N , 76 ° 32'  E
Baltoro Glacier (Karakoram)
Baltoro Glacier
drainage BralduShigarIndus
From Urdokas on the south side of the glacier the view goes upstream to Broad Peak (left) and Gasherbrum IV (right)

From Urdokas on the south side of the glacier the view goes upstream to Broad Peak (left) and Gasherbrum IV (right)

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The Baltoro Glacier is a glacier in the highest part of the Eastern Karakoram .

It is located in Baltistan , the eastern division of the Gilgit-Baltistan Territory in northern Pakistan . With a length of 62 kilometers and an area of ​​524 km² including the side glaciers, it is one of the largest valley glaciers in the world.

Larger settlements are far away. Despite its difficult access, it is possibly the most visited glacier in the area. On the one hand, this is due to the fact that with K2 and the highest peaks of the Gasherbrum group, all four eight-thousanders of the Karakoram are in its immediate vicinity. On the other hand, the valley of the Baltoro is considered to be probably the most spectacular mountain valley in the world.

European researchers first reached the Baltoro Glacier in the middle of the 19th century; Adolf Schlagintweit was probably the first in August 1856.

course

Baltoro Glacier from the ISS

The central point of the Baltoro Glacier is Concordiaplatz , where the two largest spring glaciers meet: the Upper Baltoro Glacier from the south and the Godwin-Austen Glacier from the north converge here and change their direction of flow westwards. The highest point and beginning of the glacier system is the Conway saddle ( 6044  m ). This upper part of the Baltoro Glacier is also known as the " Abruzzi Glacier ". Shortly before Concordiaplatz, the Upper Baltoro Glacier, the Vignegletscher , which leads to Gondogoro La west of the Chogolisa and offers an alternative exit from the Baltoro Valley, is joined by another important side glacier.

In the course below Concordiaplatz, the Baltoro Glacier is nestled between the Baltoro Muztagh in the north and the Masherbrum Mountains in the south, two of the highest mountain ranges in the Karakoram. Numerous other larger side glaciers unite with the Baltoro glacier: in the north these include Younghusband , Muztagh , Dunge and Trango glaciers , in the south Biarchedi , Yermanendu and Mandu glaciers are to be mentioned.

The glacier ends a little above the Paiju Camp at an altitude of 3400 m. The Braldu River, a tributary of the Shigar , which flows into the Indus near Skardu, has its source in the glacier .

glaciology

The longest distance of the glacier system is 62 km and ranges from a height of 6200 m near the Conway saddle to the tongue end 2800 meters below Paiju. The average width of the glacier is 2.1 km, the greatest width of 3.1 km is at Camp Gore I a little above the confluence of the Yermanendu Glacier. With an average gradient of only 3.9%, the glacier is quite flat compared to others in the Karakoram. In some areas it is particularly flat, for example a little south of Concordiaplatz, where the glacier falls only 21 m over a distance of two kilometers. On the other hand, the glacier is very uneven across the direction of the river. In the lower section, height fluctuations in the range of 25 meters over a horizontal distance of 140 m are not uncommon.

The end of the glacier has shifted several times over the past hundred years, but no clear trend is discernible, certainly none on a scale comparable to that of the Alpine glaciers. Measurements in 2004 come to the conclusion that the end of the glacier has only retreated by 65 meters since 1904. At the glacier tongue, the contribution of the two large source glaciers - the Godwin Austen and Upper Baltoro Glaciers - is around 40%, around 45% come from the Trango Glacier, which only flows in five kilometers above. The shifting of the end of the tongue therefore only says something about the mass budget of the entire glacier to a limited extent.

On the basis of various maps and satellite images from 1999 to 2001, the total area of ​​the glacier system, including all side glaciers that are in contact with the main glacier, was determined to be 524 km². However, only firn areas with flow characteristics were included, i.e. no areas above the bergschrund . The equilibrium line , i.e. the border between the nutrient area and the glacier's consumption area , lies in the area of ​​the Godwin-Austen glacier above 5300 m, in the area of ​​the Upper Baltoro Glacier even above 5500 m. With 29%, only a small part of the actual glacier belongs to the nutrient zone. Due to avalanches and wind movements, however, the firn areas above the actual glacier make a significant contribution to the mass budget. The total area of ​​such firn fields lying above the equilibrium line amounts to an additional 351 km², a large part of which must be included in the calculation of the mass budget of the glacier. The total area of ​​the catchment area of ​​the glacier is 1500 km², based on the end of the glacier at Paiju.

Since the large glaciers of the Karakoram make a significant contribution to supplying the semi-arid regions of Central Asia in particular with water during the dry seasons, it is of interest how the glaciers react to climate change . Investigations in 2004 showed that the Baltoro Glacier has hardly changed in the last 100 years and has responded comparatively little to climate change. One reason is likely that the glacier is relatively heavily covered with rubble. Surprisingly, however, the mass balance above Concordiaplatz at the Upper Baltoro Glacier, which has hardly any debris cover, is almost balanced. This can possibly be explained by the high contribution from avalanches and wind movements.

Web links

Commons : Baltoro Glacier  - Collection of Images, Videos, and Audio Files

Individual evidence

  1. a b c d e f g h i j k l C. Mayer, A. Lambrecht, M. Belò, C. Smiraglia, G. Diolaiuti: Glaciological characteristics of the ablation zone of Baltoro glacier, Karakoram, Pakistan. In: Annals of Glaciology. 43: 123–131, 2006 ( Summary ( Memento of the original from October 12, 2013 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this note. ) @1@ 2Template: Webachiv / IABot / www.ingentaconnect.com
  2. ^ MP Searle: Geology and Tectonics of the Karakoram Mountains. Chichester 1991, p. 271.
  3. ^ Günter Oskar Dyhrenfurth, Hettie Dyhrenfurth, Hans Ertl, André Roch: Baltoro: a Himalaya book. Page 21, B. Schwabe & co, 1939
  4. ^ W. Hagg, L. Braun: The influence of glacier retreat on water yield from high mountain areas: comparison of Alps and central Asia. In: C. De Jong, R. Ranzi, D. Collins (Eds.): Climate and hydrology in mountain areas. , Wiley & Sons, Chichester 2005, pp. 263-275, 2005, ISBN 0-470-85824-9