Glacier Blanc
Encyclopedia
| Glacier Blanc | |
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| The Glacier Blanc and the Barre des Écrins Barre des Écrins The Barre des Écrins is a mountain in the French Alps, the highest point of the Massif des Écrins, and the most southerly alpine peak in Europe that is higher than 4,000 metres.- Geography :... |
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| Location | Hautes-Alpes Hautes-Alpes Hautes-Alpes is a department in southeastern France named after the Alps mountain range.- History :Hautes-Alpes is one of the original 83 departments created during the French Revolution on 4 March 1790... , France France The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France... |
| Range Mountain range A mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain... |
Pelvoux Pelvoux Pelvoux is a commune in the Hautes-Alpes department in the Provence-Alpes-Côte d'Azur region in southeastern France.Pelvoux was bidding to be the French candidate city for the 2018 Winter Olympics.-Population:-External links:* *... , Western Alps |
| Glacier Glacier A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight... type |
Valley glacier |
| Length | 5.9 km (2002) |
| Area | 5.34 km² (2002) |
| Ice depth | up to 250 m (2005) |
| Height | to (Dôme de Neige Barre des Écrins The Barre des Écrins is a mountain in the French Alps, the highest point of the Massif des Écrins, and the most southerly alpine peak in Europe that is higher than 4,000 metres.- Geography :... ) |
| Geographical location | 44°56′29"N 6°22′50"E |
The Glacier Blanc is a glacier
Glacier
A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...
in the French
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
département of Hautes-Alpes
Hautes-Alpes
Hautes-Alpes is a department in southeastern France named after the Alps mountain range.- History :Hautes-Alpes is one of the original 83 departments created during the French Revolution on 4 March 1790...
. Its name (which means "white glacier") derives from the fact that – unlike the nearby Glacier Noir
Glacier Noir
The Glacier Noir is a glacier in the Massif des Écrins in the French Alps. It is located in the département of Hautes-Alpes.- Geography :...
("black glacier") – its surface appears pristinely white due to an absence of morainic
Moraine
A moraine is any glacially formed accumulation of unconsolidated glacial debris which can occur in currently glaciated and formerly glaciated regions, such as those areas acted upon by a past glacial maximum. This debris may have been plucked off a valley floor as a glacier advanced or it may have...
debris.
A glacier that is largely free of such moraines is generally described in French as a glacier blanc.
Geography
The Glacier Blanc begins on the northern slopes of the most southwesterly of the four-thousanderFour-thousander
A four-thousander is a mountain summit that is at least 4,000 metres above sea level. Because the highest peaks in Europe fall into this category, the summits of four-thousanders are popular in Europe with climbers and mountaineers as climbing goals...
s in the Alps
Alps
The Alps is one of the great mountain range systems of Europe, stretching from Austria and Slovenia in the east through Italy, Switzerland, Liechtenstein and Germany to France in the west....
, the high Barre des Écrins
Barre des Écrins
The Barre des Écrins is a mountain in the French Alps, the highest point of the Massif des Écrins, and the most southerly alpine peak in Europe that is higher than 4,000 metres.- Geography :...
. It is separated from the Glacier Noir to the south by the crest of Crête de l'Encoula (or Crête de l'Encula), that runs from the Barre des Écrins to the Pointe du Serre Subeyran. The upper part of the glacier is sometimes named Glacier de l'Enc(o)ula after this arête
Arete
Areté is the term meaning "virtue" or "excellence", from Greek ἈρετήArete may also be used:*as a given name of persons or things:**Queen Arete , a character in Homer's Odyssey.***197 Arete, an asteroid....
; on several older maps this name is used for the whole glacier.
With its 5.9 km-long tongue (in 2002), the Glacier Blanc is the longest glacier in the Massif des Écrins
Massif des Écrins
The mountains of the Massif des Écrins form the core of the Écrins National Park in France.-Mountains:*Barre des Écrins 4102 m*La Meije 3983 m*Ailefroide 3954 m*Mont Pelvoux 3946 m*Pic Sans Nom 3913 m*Pic Gaspard 3883 m*Le Râteau 3809 m...
and the largest in the southern French Alps. Its area of 5.34 km² (2002) is not, however, as great as that of the Glacier de la Girose and the Glacier du Mont-de-Lans, which form a common system. The Glacier Blanc is a typical valley glacier, which initially runs in a curve towards the northeast below the Barre, before its tongue turns southeast, becoming an icefall
Icefall
An icefall is a portion of some glaciers characterized by rapid flow and a chaotic crevassed surface. Perhaps the most conspicuous consequence of glacier flow, icefalls occur where the glacier bed steepens and/or narrows...
. Its average incline is about 30 %, but it is flatter in its central section than on the north slope of the Barre des Écrins or in the icefall of its lower section.
The glacier is bounded on its orographically left-hand side by, inter alia, the summits of the Roche Faurio , Pic de Neige Cordier and the Montagne des Agneaux . The Crête de l'Encoula forms the southern boundary, running from the Barre des Écrins over Barre Noir , Pointe Mettrier and Pointe de la Grande Sagne to the Pointe du Serre Subeyran . Between the peaks that surround the glacial basin are smaller side glaciers that feed the main stream.
In its centre section the main stream (excluding side glaciers) of the Glacier Blanc is about 800 to 1000 metres wide. The greatest depth of ice occurs at the Refuge des Écrins
Refuge des Écrins
Refuge des Écrins is a refuge in the Alps....
where it is up to 250 metres deep; some 30 metres less than it was in 1985. The glacier flows at a speed of around 40 metres per year in its central section (in the mid-1980s it moved at 50 m/yr) and at about 30 metres per year near its snout. Its reaction time, i.e. the time that elapses before the foot of the glacier advances or retreats due to major changes in conditions in the accumulation zone, is about 6 years in the case of the Glacier Blanc. From its head at over high to its foot, currently (2010) at about (2002: ) the Glacier Blanc descends through a height of around 1,600 metres.
The firn line on the Glacier Blanc, which separates the accumulation zone from the ablation zone
Ablation zone
Ablation zone refers to the low altitude area of a glacier or ice sheet where there is a net loss in ice mass due to melting, sublimation, evaporation, or calving. The ablation zone is delineated by the equilibrium line altitude , or snow line, which separates the ablation zone and the high...
, lies on the northern slopes at a height of about , and on the southern flanks at about . The glacier's mass balance
Mass balance
A mass balance is an application of conservation of mass to the analysis of physical systems. By accounting for material entering and leaving a system, mass flows can be identified which might have been unknown, or difficult to measure without this technique...
, an indicator of its health, has not been fully investigated.
The Glacier Blanc drains via the Torrent du Glacier Blanc, the Gyr, the Gyronde, the Durance
Durance
The Durance is a major river in south-eastern France.Its source is in the south-western Alps, in Montgenèvre ski resort near Briançon and it flows south-west through the following départements and cities:* Hautes-Alpes: Briançon, Embrun.* Alpes-de-Haute-Provence: Sisteron, Manosque.* Vaucluse:...
and finally the Rhône
Rhône
Rhone can refer to:* Rhone, one of the major rivers of Europe, running through Switzerland and France* Rhône Glacier, the source of the Rhone River and one of the primary contributors to Lake Geneva in the far eastern end of the canton of Valais in Switzerland...
into the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
.
Access
From Pré de Madame Carle and its Refuge Cézanne hut, where the road from the village of AilefroideAilefroide
The Ailefroide is a mountain in the Massif des Écrins in the French Alps, and is the third highest peak in the Dauphiné Alps after the Barre des Écrins and La Meije. It lies at the south-western end of the Mont Pelvoux–Pic Sans Nom–Ailefroide ridge....
in the Vallouise
Vallouise
Vallouise is a commune in the Hautes-Alpes department in southeastern France.-Population:-References:*...
ends at a large car park, a popular alpine walking trail runs up to the Refuge du Glacier Blanc , from where the glacier is visible. Around 100 metres lower down the trail passes the Ancien Refuge Tuckett, a small accommodation hut from the end of the 19th century. This primitive hut that, today, is an exhibit, was built immediately next to a large stone slab that had hitherto acted as a camping place from which the area could be explored. The shelter was named the Hotel Tuckett, after the alpinist Francis Fox Tuckett
Francis Fox Tuckett
Francis Fox Tuckett FRGS was an English mountaineer. He was vice-president of the Alpine Club from 1866 to 1868, and a Fellow of the Royal Geographical Society.-Life and family:...
.
Two hours by foot further on the Refuge des Écrins is situated high above the Glacier Blanc on a prominent rocky 'pulpit', at a height of , with expansive views of the area. The hut trail runs for the most part immediately above the glacier and should only be attempted by fully equipped high-altitude alpinists because of the danger of falling into a crevasse
Crevasse
A crevasse is a deep crack in an ice sheet rhys glacier . Crevasses form as a result of the movement and resulting stress associated with the sheer stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement...
. The high alpine base with 119 beds is often overbooked during the peak season.
From La Bérarde , the alpinist centre in the Haut Vénéon, the Glacier Blanc may be reached over the Col des Écrins at the end of the Val de Bonne Pierre. This is a day's tour at grade
Grade (climbing)
In rock climbing, mountaineering and other climbing disciplines, climbers give a climbing grade to a route that concisely describes the difficulty and danger of climbing the route...
PD. The western approach to the col is steep and challenging, although wire cables improve safety in its upper section. On the eastern side the Glacier Blanc reaches right up to the narrow wind gap.
Historic development
As with almost all alpine glaciers, the foot of the Glacier Blanc has retreated. In earlier times, most recently in 1866., it formed a single glacial system with its southern neighbour, the moraine-covered Glacier Noir, whose streams joined one another above the Pré de Madame Carle. During the Small Ice Age the combined ice system reached its maximum extent in 1815 and ended roughly at the height of the Cezanne Hut .As of 2010 the tongue of the Glacier Blanc lies at a height of about . In the 20th century it is estimated that it retreated by about 1 km, accompanied by a reduction in area of some 2 km². Between 1989 and 1999 alone the glacier lost about 210 metres; it retreated a further 300 metres in the years to 2006. The ice thickness in the centre reduced during the period from 1981 to 2002 by 13.5 metres, an estimated loss in volume of 70 million m³ of ice.