Glacier Blanc
| Glacier Blanc | ||
|---|---|---|
 The Glacier Blanc with the Barre des Écrins |
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| location | Hautes-Alpes , France | |
| Mountains | Pelvoux , Western Alps | |
| Type | Valley glacier | |
| length | 5.9 km (2002) | |
| surface | 5.34 km² (2002) | |
| Exposure | Northeast / tongue southeast | |
| Altitude range | 4015 m - 2400 m (highest point on the Dôme de Neige ) | |
| Tilt | ⌀ 16.7 ° (30%) | |
| width | ⌀ 0.8 km; Max. 1 km | |
| Ice thickness | Max. 250 m (2005) | |
| Coordinates | 44 ° 56 '29 " N , 6 ° 22' 50" E | |
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| drainage | via Torrent du Glacier Blanc , Gyr , Gyronde , Durance and Rhône to the Mediterranean | |
The Glacier Blanc is a glacier in the French department of Hautes-Alpes . It owes its name (»White Glacier«) to the fact that - unlike the neighboring Glacier Noir (»Black Glacier«) - its surface appears immaculately clean due to the absence of moraine debris.
Glaciers that are largely free of moraine debris are generally referred to in French as glacier blanc .
geography
The Glacier Blanc has its origin on the north side of the most southwestern four-thousand-meter peak in the Alps , the 4102 m high Barre des Écrins . It is separated from the southern Glacier Noir by the Crête de l'Encoula (different spelling: Crête de l'Encula ) called the ridge, which crosses from the Barre des Écrins to the Pointe du Serre Subeyran . The upper part of the glacier is sometimes referred to as the Glacier de l'Enc (o) ula after this ridge ; in some older maps this name is used for the entire glacier.
With its (in 2002) 5.9 km long tongue, the Glacier Blanc is the longest glacier in the Écrins massif . However, its area of 5.34 km² (2002) does not come close to that of Glacier de la Girose and Glacier du Mont-de-Lans , which form a common system. The Glacier Blanc is a typical valley glacier that initially stretches in a north-easterly direction below the bar, before its tongue turns to the south-east in an ice break. Its average slope is about 30%. However, it is significantly lower in the flat central part than in the north flank of the Barre des Écrins or in the lower tongue area with the icefall.
The glacier is bounded on its orographic left side by the peaks of Roche Faurio ( 3730 m ), Pic de Neige Cordier ( 3614 m ) and the Montagne des Agneaux ( 3664 m ). The Crête de l'Encoula stretches as a southern boundary from the Barre des Écrins via Barre Noir ( 3661 m ), Pointe Mettrier ( 3664 m ), Pointe de la Grande Sagne ( 3660 m ) to the Pointe du Serre Subeyran ( 3472 m ). Small side glaciers are embedded between the peaks that surround the glacier basin and feed the main stream.
In its central part, the main stream (without side glaciers) of Glacier Blanc is about 800 to 1000 meters wide. The greatest ice depth is at the Refuge des Écrins up to 250 meters; it has thus decreased by around 30 meters since 1985. The glacier flows in its central area at a speed of around 40 (in the mid-80s of the last century 50), in the area of the lower tongue of about 30 meters per year. The reaction period that elapses until the bottom tongue reacts to significantly changed conditions in the nutrient area by pushing or retreating is about 6 years for Glacier Blanc. From its origin at an altitude of over 4000 m to the glacier gate at currently around 2400 m (2002: 2315 m ), the Glacier Blanc overcomes an altitude difference of around 1600 meters.
The firn line that separates the nutrient zone from the Zehrgebiet lies at Glacier Blanc on the north-facing slopes at around 2750 m , on the south-facing flanks at around 2950 m . The mass balance of the glacier has not yet been fully investigated.
The Glacier Blanc drains into the Mediterranean via the Torrent du Glacier Blanc , the Gyr , the Gyronde , the Durance and finally the Rhône .
Development
From the Pré de Madame Carle with the Refuge Cézanne , where the road from the village of Ailefroide in Vallouise ends at a large car park, an alpine, well-traveled hiking trail leads up to the Refuge du Glacier Blanc ( 2542 m ), which is within sight of the glacier tongue. Around 100 meters below the hut, the path passes the Ancien Refuge Tuckett , a small accommodation building from the late 19th century. The primitive hut, which is now used as an exhibition object, was built right next to a large stone slab, which previously served as a bivouac site for those developing the area. After the English mountaineer Francis Fox Tuckett , the refuge was named Hotel Tuckett with British humor .
Two hours walk above stands the refuge of the Écrins to 3170 m height on a promising rock pulpit high above the Glacier Blanc. A large part of the ascent to the hut leads directly over the glacier and can only be mastered by fully equipped high alpinists due to the risk of crevasses falling. The high-alpine base with 119 camps is often hopelessly overcrowded in the high season.
From La Bérarde ( 1713 m ), the alpine center in the Haut Vénéon, you reach the Glacier Blanc via the Col des Écrins ( 3367 m ), which closes the Val de Bonne Pierre . It is a day tour with difficulty PD. The western approach to the Col is steep and demanding, although wire ropes make it easier to secure in the upper part. On the eastern side, the Glacier Blanc extends right up to the narrow notch.
Historical development
Like almost all Alpine glaciers, the tongue of Glacier Blanc is melting back. In earlier times, most recently in 1866, it formed a single glacier system with its southern neighbor, the debris-covered Glacier Noir, whose tongues united above the Pré de Madame Carle. During the Little Ice Age , the combined ice bodies reached their maximum extent in 1815 and ended roughly at the height of the Cézanne hut ( 1874 m ).
Today (2010) the tongue of Glacier Blanc lies at an altitude of about 2400 m . For the 20th century, the decline is estimated at around 1 km, which was accompanied by a loss of area of around 2 km². Between 1989 and 1999 alone, the glacier lost around 210 meters, another 300 meters followed in the years up to 2006. The ice thickness decreased by an average of 13.5 meters between 1981 and 2002, with an estimated loss of 70 million m³ of ice.
Web links
- Les cahiers thématiques du Parc national des Écrins - N ° 1 - Les glaciers. (PDF) Parc national des Écrins, December 2005, accessed on October 14, 2010 (French).
- Hervé Cortot, Marcel Chaud: Le glacier Blanc. (doc) L'Association des Professeurs de Biologie et Géologie Aix-Marseille, July 2005, archived from the original on September 4, 2011 ; Retrieved September 29, 2010 (French, contains a nice graphic representation of a longitudinal section through the glacier).
- Extensive information on Glacier Blanc on vallouimages.com (French)
- Information on Glacier Blanc from l'école de Magnières, l'Académie de Nancy-Metz (French)
Individual evidence
- ↑ a b c d See Les cahiers thématiques du Parc national des Écrins - N ° 1 - Les glaciers. (PDF) (No longer available online.) Parc national des Écrins, December 2005, archived from the original on November 10, 2010 ; Retrieved October 14, 2010 (French). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ a b c Website of the municipality of Pelvoux in Vallouise ( Memento of the original from November 26, 2006 in the web archive archive.today ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ a b c d e Antoine Rabatel, Jean-Pierre Dedieu, Emmanuel Thibert, Anne Letréguilly, Christian Vincent: 25 years (1981-2005) of equilibrium-line altitude and mass-balance reconstruction on Glacier Blanc, French Alps, using remote- sensing methods and meteorological data. (PDF) Journal of Glaciology, Vol. 54, No. 185, pp. 307-314, 2008, accessed September 30, 2010 (English).
- ↑ a b c d Hervé Cortot, Marcel Chaud: Le glacier Blanc. (doc) L'Association des Professeurs de Biologie et Géologie Aix-Marseille, July 2005, archived from the original on September 4, 2011 ; Retrieved September 29, 2010 (French, contains a nice graphic representation of a longitudinal section through the glacier).
- ↑ The at fr: Glacier Blanc and information on Glacier Blanc from l'école de Magnières, l'Académie de Nancy-Metz ( Memento of the original of July 21, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked . Please check the original and archive link according to the instructions and then remove this notice. Said speeds of up to 350 meters per year appear to be far too high.
- ↑ Page no longer available , search in web archives: Tim Stott, Professor of Physical Geography & Outdoor Education, Liverpool John Moores University
- ↑ According to another source, 1876 is named as the year Glacier Blanc and Glacier Noir separated, cf. Les cahiers thématiques du Parc national des Écrins - N ° 1 - Les glaciers, page 18. (PDF) (No longer available online.) Parc national des Écrins, December 2005, archived from the original on November 10, 2010 ; Retrieved October 14, 2010 (French). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ^ Robert Vivian: Le glacier Blanc. (PDF) (No longer available online.) Revue de géographie alpine, Année 1967, Volume 55, Numéro 55-4, pp. 729–732, 1967, archived from the original on September 24, 2015 ; Retrieved September 28, 2010 (French). Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Anne Letréguilly and Louis Reynaud: Past and forecast fluctuations of Glacier Blanc. (PDF) Annals of Glaciology 13, International Glaciological Society, pp. 159–163, 1989, accessed on September 28, 2010 (English).
- ↑ See explanations on vallouimages.com
