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16-737: The upper accumulation zones of the Brenva Glacier are enclosed by the Aiguille Noire de Peuterey , the Aiguille Blanche de Peuterey , Mont Blanc de Courmayeur , Mont Blanc , Mont Maudit , the Brenva Arête , the Tour Ronde , and the Aiguille de la Brenva . The Brenva Glacier is formed from three branches, and descends steeply in a south-easterly direction, passing through a narrow neck (known as

32-622: A col below the Tour Ronde, accessed from the Skyway Monte Bianco , but is only suitable for advanced freeride/snowboarders and skiers. The old tongue of the glacier reaches down low into the Val Veni and is easily reached on foot from Entrèves or Courmayeur. It takes about six hours for alpine climbers to reach the Brenva Bivouac from Courmayeur. Accumulation zone On a glacier ,

48-585: A further 7.8 to 9.9 million cubic metres of snow and ice. Four additional pre-20th century rockfall events have also been identified on the Brenva Glacier. These occurred in 1767 AD; the early 14th century; between 426 and 615 AD; and between 2750 and 2350 calendar years BP. Evidence for the glacier's re-advance in the past has been found in the form of ancient logs buried in moraine deposits. These indicate that those moraines themselves had once been exposed and forested, but then subsequently reburied by new moraines during another period of glacial advance. Retreat of

64-480: A very large rock promontory between the upper branches of the glacier, the Brenva Bivouac ( French : Bivouac de la Brenva ) is a very small mountain refuge providing bivouac shelter for up to five people. It is at an altitude of approximately 3140 metres above sea level. Open all year round, it is not attended, and is owned by the Italian Alpine Club . The upper slopes of the Brenva Glacier can be reached via

80-471: The accumulation zone is the area above the firn line, where snowfall accumulates and exceeds the losses from ablation , ( melting , evaporation , and sublimation ). The annual equilibrium line separates the accumulation and ablation zone annually. The accumulation zone is also defined as the part of a glacier's surface, usually at higher elevations, on which there is net accumulation of snow, which subsequently turns into firn and then glacier ice. Part of

96-422: The Brenva Glacier since 1988 has exposed its lateral moraines which served to channel the massive 1997 rock avalanche between them. By contrast, earlier advance of the glacier that has started in 1913 served to raise the ice level above the moraines, thus causing the rock in that avalanche to come to rest outside of the moraines. The major rockfall events on the Brenva Glacier have deposited so much rock debris that

112-693: The Club Alpino Italiano, along with Touring Club Italiano , published between 1908 and 2013 the Guida dei Monti d'Italia (in English Guidebook to the Italian mountains ), a series of guidebooks covering all the mountain ranges of Italy. Italian military troops adopted a grey-green uniform during World War I. Luigi Brioschi, president of the Milanese section of the C.A.I. (Italian Alpine Club) in 1905 introduced

128-494: The Pierre à Moulin) at 2,460 to 2,550 metres (8,070 to 8,370 ft) above sea level (asl), and then falls sharply as a serac field, before reforming as a broad rock-covered glacial tongue. Since 2004, the lower section below the serac field has become completely separated from the upper section, resulting in the active front of the glacier now being at 2,350 m (7,710 ft) asl – some 1,000 metres (3,300 ft) higher than it

144-471: The floor of Val Veny . It killed two skiers and built a 25 m (82 ft)-high dam of snow and ice which temporarily blocked the Dora Baltea river, whilst the air blast destroyed mature forest trees and buildings on the opposite side of the valley. The total volume of rock, snow and ice was estimated at four million cubic metres. Further investigation suggested that the avalanche was not caused directly by

160-403: The glacier has a recorded speed of flow of 180 metres (590 ft) per year. Minor rockfalls occur very frequently from the steep mountainsides above the Brenva Glacier. On 18 January 1997 a major rockfall occurred at around 3,725 m (12,221 ft) which initiated an enormous avalanche that travelled 5.5 km (3.4 mi) horizontally, descending over 2,285 m (7,497 ft) into

176-454: The glacier where snow builds up and turns to ice moves outward from there. This glaciology article is a stub . You can help Misplaced Pages by expanding it . Club Alpino Italiano The Club Alpino Italiano is the senior Italian alpine club which stages climbing competitions, operates alpine huts , marks and maintains paths, and is active in protecting the Alpine environment . It

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192-486: The greatest numbers of members came from Lombardy (88,057), Veneto (54,948), and Piedmont (51,396). Its most famous achievement is the 1954 Italian Karakoram expedition to K2 that made the first successful ascent of K2 . The CAI operates 388 mountain huts , 251 bivouacs and 118 smaller huts and shelters throughout the Italian Alps , for an overall capacity of over 23,500 beds. Among many other publications

208-447: The normal balance between the upper accumulation zone and lower ablation zone has been compromised. For example, the 1920 rock avalanche added so much additional material to the already rock-covered lower zone, that ablation was significantly reduced. This effectively insulated that part of the glacier, resulting in its advance by an extra 490 metres between 1920 and 1941, and at a time when other glaciers nearby were retreating. Located on

224-596: The rockfall, but through seismic shock causing seracs to collapse which, in turn, then initiated the snow and ice avalanche. The rock avalanche itself has been described as a classic example of a sturzstrom . The lower section of the Brenva Glacier is covered in rock – the remnants of earlier rockfalls in November 1920 from the east face of the Grand Pilier d'Angle . These were four separate events, consisting of between 2.4 to 3.6 million cubic metres of rock, which then mobilised

240-663: Was founded in Turin in 1863 by the then finance minister, and mountaineer, Quintino Sella ; together with the Swiss Alpine Club , founded in the same year, it is the second oldest Alpine Club in the world, only preceded by the British Alpine Club . After First World War and the annexation of Trento and Trieste to Italy, it absorbed the "Società degli Alpinisti Tridentini" and the "Società Alpina delle Giulie". As of 2020, it had 306.255 members, 512 sections and 316 sub-sections;

256-505: Was previously. As at 1989, the Brenva Glacier had a maximum length of 7.64 km (4.75 mi), and an area of 8.06 km (3.11 sq mi), making it the eighth largest in Italy by area. Like most alpine glaciers, it has been retreating since that time, and is now approximately 6.7 km (4.2 mi) in length, but still remains the second longest. It has an area of approximately 7 km (2.7 sq mi) and, in its upper region,

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