Snow

Snow
/snoh/, n.
Sir Charles Percy (C. P. Snow), 1905-80, English novelist and scientist.
[1665-75]

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I
Solid form of water that crystallizes in the atmosphere and falls to the Earth, covering about 23% of the Earth's surface either permanently or temporarily.

Snowflakes are formed by crystals of ice that generally have a hexagonal pattern. Snow cover has a significant effect on climate and on plant, animal, and human life. By increasing the reflection of solar radiation and interfering with the conduction of heat from the ground, it induces a cold climate. The low heat conduction protects small plants from the effects of the lowest winter temperatures; on the other hand, late disappearance of snow in the spring delays the growth of plants.
II
(as used in expressions)
Snow Charles Percy
Baron Snow of the City of Leicester

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      the solid form of water that crystallizes in the atmosphere and, falling to the Earth, covers, permanently or temporarily, about 23 percent of the Earth's surface.

      A brief treatment of snow follows. For full treatment, see climate: Snow and sleet (climate).

      Snow falls at sea level poleward of latitude 35° N and 35° S, though on the west coast of continents it generally falls only at higher latitudes. Close to the equator, snowfall occurs exclusively in mountain regions—at elevations of about 4,900 m (16,000 feet) or higher.

      Snow cover has a significant effect on climate and on plant, animal, and human life. By increasing the reflection of solar radiation and interfering with the conduction of heat from the ground, it induces a cold climate. The low heat conduction protects small plants from the effects of the lowest winter temperatures; on the other hand, the late disappearance of snow in the spring delays the growth of plants. When snow melts in the spring, the resulting runoff feeds rivers and supplies water for irrigation and other human enterprises. Heavy snowfalls can severely hinder transporation in variable moderate climates but provides a firm surface for travel in remote Arctic, Antarctic, and mountainous areas, using traditional dogsleds or snowshoes or modern snowmobiles.

 Snowflakes are formed by crystals of ice that generally have a hexagonal pattern, often beautifully intricate (see video—>). The size and shape of the crystals depend mainly on the temperature and the amount of water vapour available as they develop. At temperatures above about -40° C (-40° F), ice crystals form around minute particles of dust or chemical substances that float in the air; at lower temperatures, crystals form directly from water vapour. If the air is humid, the crystals tend to grow rapidly, develop branches, and clump together to form snowflakes. In colder and drier air, the particles remain small and compact. Frozen precipitation has been classified into seven forms of snow crystals and three types of particles—graupel (granular snow pellets, also called soft hail), sleet (partly frozen ice pellets), and hail (hard spheres of ice).

      The texture and density of fallen snow undergo constant change. Snow on the ground tends to become increasingly dense, and, where it survives spring and summer melting for years, it may turn into ice and form a glacier. On hillsides when temperature changes reduce the coherence of snow particles in the snow cover, gravity and viscosity may overcome friction, causing snow slides and avalanches.

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Universalium. 2010.

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Look at other dictionaries:

  • Snow — Snow, n. [OE. snow, snaw, AS. sn[=a]w; akin to D. sneeuw, OS. & OHG. sn[=e]o, G. schnee, Icel. sn[ae]r, snj[=o]r, snaj[=a]r, Sw. sn[ o], Dan. snee, Goth. snaiws, Lith. sn[ e]gas, Russ. snieg , Ir. & Gael. sneachd, W. nyf, L. nix, nivis, Gr. acc.… …   The Collaborative International Dictionary of English

  • Snow — bezeichnet: das englische Wort für Schnee Snow (Fluss), einen Fluss Snow (Codec), einen Wavelet basierenden Videocodec Snow (Musiker), einen kanadischen Rapper Snow (Album), das sechste Studioalbum von Spock s Beard Snow ist der Familienname… …   Deutsch Wikipedia

  • SNOW (E. P.) — SNOW EDGAR PARKS (1905 1972) Durant plus d’une décennie, Edgar Snow fut sans doute le plus aventureux et le plus entreprenant des journalistes en Chine et il est indiscutablement le premier à avoir témoigné de l’importance d’une révolution en… …   Encyclopédie Universelle

  • Snow — (en inglés nieve), puede referirse a: John Snow (1813–1858), médico inglés; John W. Snow (n. 1939), 73º secretario del Tesoro de los Estados Unidos; La Isla Snow en la Antártida; El sobrenombre de Darrin O Brien (n. 1969), músico de reggae… …   Wikipedia Español

  • snow — snow; snow·do·nian; snow·i·ly; snow·i·ness; snow·less; snow·man; snow·mo·bil·ing; snow·mo·bile; snow·mo·bil·er; snow·mo·bil·ist; …   English syllables

  • snow — [snō] n. [ME < OE snaw, akin to Ger schnee < IE base * sneigwh , to snow, * snoigwhos, snow > OIr snechta, Russ snieg, L nix (gen. nivis)] 1. particles of water vapor which when frozen in the upper air fall to earth as soft, white,… …   English World dictionary

  • snow´i|ly — snow|y «SNOH ee», adjective, snow|i|er, snow|i|est. 1. having snow: »a snowy day. 2. covered with snow: »a snowy roof …   Useful english dictionary

  • snow|y — «SNOH ee», adjective, snow|i|er, snow|i|est. 1. having snow: »a snowy day. 2. covered with snow: »a snowy roof …   Useful english dictionary

  • SNOW — 1.0 and 2.0 are two word based synchronous stream ciphers developed by Thomas Johansson and Patrik Ekdahl at Lund University. SNOW 1.0, originally simply SNOW, was submitted to the NESSIE project. The cipher has no known intellectual property or… …   Wikipedia

  • Snow — Snow, v. t. To scatter like snow; to cover with, or as with, snow. Donne. Shak. [1913 Webster] …   The Collaborative International Dictionary of English

  • snow — ► NOUN 1) atmospheric water vapour frozen into ice crystals and falling in light white flakes or lying on the ground as a white layer. 2) (snows) falls of snow. 3) a mass of flickering white spots on a television or radar screen, caused by… …   English terms dictionary

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