At a certain height in the mountains more than a meter of snow falls during the year. Snow accumulates and is compressed into ice. The resulting ice slowly slides down the gorge, taking its shape. Small glaciers flow at a speed of about 10 meters per year. The snow that accumulated above during the winter periods, and the melting of ice in the summer form the circulation process. Glaciers change every year. New cracks are created and old cracks disappear.
Glaciers, the formation of glaciers, forms of glacial cracks, melting glaciers, a diagram of the forms of mountainous terrain.
The upper part of the glaciers is the area where the process of accumulation of snow cover occurs. The combination of repeated processes of freezing, skalavin, the movement of the glacier, breaking off pieces of rock, and their further flow (transfer) downward leads to the formation of moraines.
A transverse crack that appears between the summit take-off or a steep slope and the main horizontal part of the glacier is called the bergschrund. In summer, the snow or snow line is the transition zone of a part of a glacier covered with snow (closed glaciers) to a part of a glacier without snow cover (open glaciers).
When the angle of the glacier sharply increases, its surface cracks, forming flakes and towers of unstable pieces of ice (blocks), reaching a height of ten or more meters. These pieces of ice are called seraks, and glaciers in this place are called icefalls..
Transverse cracks form when the angle of the glacier does not change sharply. Such cracks perpendicular to the glacier reach 50-40 meters in depth and often have different expansion (opening and narrowing cracks).
Longitudinal cracks form in places where the melting of the central part of the glacier occurs rather than along the edges. Forcing him to slide faster along the slope. The edges of the glacier, clinging to the rocks, contribute to the formation of perpendicular cracks.
Ice crack shapes.
This is the name of its lower part, sliding along the gorge and ending with a moraine or “ram’s foreheads”.
These are smooth rocky outcrops, usually with a positive angle, remaining on the terrain after the glacier has melted. Characterized by the absence on them of any relief for climbing.
“Nunatak” (grenl. Nunataaq).
A rocky peak, mountain ridge or hill protruding above the surface of the ice sheet or mountain glacier completely surrounded by ice.
A thawing crack in the upper part of the firn field (densely packed, grainy and partially recrystallized snow) or a glacier formed under the influence of a warm air stream from the rocks. Such a crack forms between a rock and a snow-ice slope..
Scheme of mountain relief.
Glaciers melt after climate change. Since the mid-20th century, glaciers have receded sharply due to melting due to global warming. From the end of the 1880s to 2011, the Bezengi glacier retreated by more than 1.7 km, and from the beginning to the middle of the 19th century by 2.5 km.
These changes seriously affect the state of the routes:
The early discovery of cracks and bergschrights complicates the approach of many routes.
Many snow routes today turn into ice or vice versa, completely melt.
Melting ice contributes to rockfall formation.
Access to many overnight stays becomes difficult due to overcoming the melted steps of the glacier.
Based on the book School of mountaineering, a training manual.