avalanche


Also found in: Dictionary, Thesaurus, Medical, Legal, Acronyms, Wikipedia.
Related to avalanche: Avalanche breakdown

avalanche,

rapidly descending large mass of snow, ice, soil, rock, or mixtures of these materials, sliding or falling in response to the force of gravity. Avalanches, which are natural forms of erosion and often seasonal, are usually classified by their content such as a debris or snow avalanche. Speeds can reach over 200 mi per hr (300 km per hr). They are triggered by such events as earthquake tremors, human-made disturbances, or excessive rainfall on high gradient slopes, often where materials are loosely consolidated or weathered. Avalanches of snow result when weak layers within a snowpack fail to support the weight of the snow above it and collapse, causing the overlying snow to break free and flow downhill. Destruction from avalanches results both from the avalanche wind (the air pushed ahead of the mass) and from the actual impact of the avalanche material.

avalanche

A process such as that in which a single ionization leads to a large number of ions. The electrons and ions produced ionize more atoms, so that the number of ions multiplies quickly. See Geiger counter.

Avalanche

 

(Russian lavina, from the German Lawine, from the Late Latin labina, “landslide”), masses of snow on mountain slopes that begin moving and slide downward.

Avalanches may occur in all mountain regions where there are stable snow covers. Snow accumulated on mountain slopes is freed when (1) the slopes are overloaded with snow during a storm or as a result of low cohesive force between new snow and the underlying surface in the first two days after a snowfall ends (dry snow avalanches); (2) a water lubricant is formed between the bottom surface of the snow and the underlying surface of the slope during thaws or rains (wet snow avalanches); or (3) a loose layer consisting of disconnected deep-lying frost crystals forms in the lower parts of the snow stratum (sublimation diaphthore-sis avalanches). The reason for the loosening is that temperatures are higher in the lower snow horizons, and water vapor moves from there to the higher (and colder) horizons. This causes evaporation of snow in the warm horizon, and it becomes the slide horizon.

Three types of avalanches may be distinguished, depending on the nature of snow movement along the slopes: osovy (snowslide) avalanches, which slide along the entire surface of the slope without channels; chute avalanches, which move in hollows, ravines, and eroded furrows; and leaping avalanches, which fall freely from ledges. The average speed of avalanches is 20–30 m per sec. The fall of an avalanche is usually accompanied by a low whistle (if dry snow is falling), by a scraping sound (if the snow is wet), or by a deafening roar (if an avalanche wind occurs). The frequency of avalanches and their size depend on the morphology of the avalanche. Chute avalanches from deep hollows occur frequently but are not large; avalanches rarely originate by disruption of cirques, but when they do, such avalanches reach huge proportions. The remains of avalanches usually form névé basins.

Avalanches have enormous destructive force. They cause major disasters and prevent the normal operation of roads, industrial installations, and sports facilities. Preventive measures include maintaining a mountain avalanche service and mountain engineering surveillance, forecasting the time when avalanches will come down, and artificially setting off avalanches by firing guns and by setting off explosions. Engineering protective measures consist in preventing snow from sliding in avalanche channels by planting trees on the slopes and reinforcing them with support structures, using guide dikes to divert avalanches from the objects being protected, and running the avalanches over the object by means of suspended covers and tunnels. In areas subject to avalanches special maps are compiled indicating regions with significant, medium, and slight danger and also regions with potential danger—areas that are safe at the present time but could become dangerous if forests were cut, earth were removed from the slopes, and so on.

REFERENCES

Tushinskii, G. K. Ledniki, snezhniki, laviny Sovetskogo Soiuza. Moscow, 1963.
Losev, K. S. Laviny SSSR. Leningrad, 1966.
Lavinoopasnye raiony Sovetskogo Soiuza. Moscow, 1970.
Inzhenernaia gliatsiologiia. Moscow, 1971.
Karta lavinoopasnykh raionov Sovetskogo Soiuza. Moscow, 1971.

G. K. TUSHINSKII

What does it mean when you dream about an avalanche?

An avalanche signifies being overwhelmed, especially by emotions that could not be experienced or previously expressed owing to the “frozen” nature of the individual.

avalanche

[′av·ə‚lanch]
(electronics)
The cumulative process in which an electron or other charged particle accelerated by a strong electric field collides with and ionizes gas molecules, thereby releasing new electrons which in turn have more collisions, so that the discharge is thus self-maintained. Also known as avalanche effect; cascade; cumulative ionization; electron avalanche; Townsend avalanche; Townsend ionization.
Cumulative multiplication of carriers in a semiconductor as a result of avalanche breakdown. Also known as avalanche effect.
(hydrology)
A mass of snow or ice moving rapidly down a mountain slope or cliff.

avalanche

1. 
a. a fall of large masses of snow and ice down a mountain
b. a fall of rocks, sand, etc.
2. Physics a group of ions or electrons produced by a single ion or electron as a result of a collision with some other form of matter

Avalanche

(dreams)
The material which makes up the avalanche is snow, and snow is frozen water. Water symbolizes your emotions, the unconscious, and, at times, life itself. Therefore, this dream is about rapidly and violently descending emotions and thoughts. Emotions which may have been repressed have finally been unlocked and may be overwhelming you. You may have this dream during emotionally turbulent times of your life, or in your dreams you may be remembering and reliving some difficult emotional experiences. Old dream interpretation books say that burial in an avalanche may result in good luck in the near future. Therefore, they think that it is a dream of the contrary.
References in classic literature ?
The avalanche had shaken and slid a little forward, but it did not yet crash down.
Once more also we were able to communicate with Zambo, who had been terrified by the spectacle from afar of an avalanche of apes falling from the edge of the cliff.
The danger was not from rock and avalanche, but from something yet more romantic.
I fell under that titular avalanche a torn and blighted thing.
Amid this tornado, an entire caravan, disorganized, broken, and overthrown, was disappearing beneath an avalanche of sand.
His proofs were corrected; and the volume was to come out among the publications of the early spring, when the public might be supposed to have recovered from the avalanche of Christmas books.
The hounds at the same moment rushed into the grotto like an avalanche, and the depths of the cavern were filled with their deafening cries.
The grapnel smashed down a steeply sloping roof, followed by an avalanche of broken tiles, jumped the street amidst shrieks and cries, and smashed into a plate-glass window with an immense and sickening,impact.
It was necessary to let the French reach Shamshevo quietly without alarming them and then, after joining Dolokhov who was to come that evening to a consultation at a watchman's hut in the forest less than a mile from Shamshevo, to surprise the French at dawn, falling like an avalanche on their heads from two sides, and rout and capture them all at one blow.
Dorothea's feelings had gathered to an avalanche, and there could be no further preparation.
At my words the others of the first line, who had been interested spectators of my tactics, seized upon great boulders or bits of rock, whichever came first to their hands, and, without, waiting for a command from Gr-gr-gr, deluged the terrified cave men with a perfect avalanche of stone.
A veritable avalanche of savage beasts rolled over him and threw him heavily to the ground.