fog

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For more information on fog, visit Britannica.com.

A cloud comprising waterdroplets or (less commonly) ice crystals formed near the ground and resulting in a reduction in visibility to below 0.6 mi (1 km). This is lower than that occurring in mist, comprising lower concentration of waterdroplets, and haze, comprising smaller-diameter aerosol particles.

Fog results from the cooling of moist air below its saturation (dew) point. Droplets form on hygroscopic nuclei originating from ocean spray, combustion, or reactions involving trace chemicals in the atmosphere. Visibility is reduced even more when such nuclei are present in high concentrations and faster cooling rates activate a larger fraction of such nuclei. Thus, polluted fog, with more numerous smaller droplets, results in lower visibility for a given water content. See also Dew point.

Haze, the precursor to fog and mist, forms at relative humidity below 100% to about 80%. It is composed of hygroscopic aerosol particles grown by absorption of water vapor to a diameter of about 0.5 micrometer, concentration 1000 to 10,000 per cubic centimeter. Fog and mist form as the relative humidity increases just beyond saturation (100%), so that larger haze particles grow into cloud droplets with a diameter of 10 μm and a concentration of several hundred per cubic centimeter. Fog and mist are a mix of lower-concentration cloud droplets and higher-concentration haze particles. By contrast, smog is formed of particles of 0.5–1-μm diameter, produced by photochemical reactions with organic vapors from automobile exhaust. See also Atmospheric chemistry; Humidity; Smog.

In computer graphics, simulating the effects of fog, smoke and haze. Similar to alpha blending, fogging is very computational. If the operation is performed in the graphics accelerator, the results are displayed considerably faster. See alpha blending.

A Fogged Image

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Photographic defect caused by a deposit of silver on the image areas, creating a cloudy area. Fog is caused by incorrect exposure of the film or by a poorly balanced chemical developing solution. Photographs with fog are usually discarded.

noun

1. A thick, heavy atmospheric condition offering reduced visibility because of the presence of suspended particles: brume, haze, mist, murk, smaze. See clear/unclear.
2. A stunned or bewildered condition: befuddlement, bewilderedness, bewilderment, daze, discombobulation, muddle, mystification, perplexity, puzzlement, stupefaction, stupor, trance. See awareness/unawareness.

verb

To make dim or indistinct: becloud, bedim, befog, blear, blur, cloud, dim, dull, eclipse, gloom, mist, obfuscate, obscure, overcast, overshadow, shadow. See clear/unclear.

Definition: heavy mist which reduces visibility
Antonyms: clearness

n

Definition: mental unclarity; obscurity
Antonyms: clarity, cognizance, understanding

v

Definition: muddle, obscure
Antonyms: clear up, explain

A cloud of water droplets suspended in the air, limiting visibility to less than 1000 m. Fog forms when a layer of air close to a surface becomes slightly supersaturated and produces a layer of cloud, that is, when vapour-laden air is cooled below dew point. In advection fog, this cooling is brought about as warm, moist air passes over cold sea currents, such as the Labrador current. Radiation fog forms during cloudless autumn nights when strong terrestrial radiation causes ground temperatures to fall. Moist air is chilled by contact with the ground surface. The fog lingers until it is dispersed by warm sunlight.

Where cold air streams cross warm waters, steam fog forms. This is common when relatively warm surface air over lakes in frost hollows convects into the cold katabatic airflow above it, and is also the mechanism behind Arctic sea smoke. Frontal fog forms when fine rain falling at a warm front is chilled to dew point as it falls through cold air at ground level. Hill fog is not true fog.

Fog, a darkening of part or all of a negative (or lightening of a transparency) that is not part of the optical image. There are three main kinds: light fog, caused by stray light leaking into the camera (or processing area); chemical fog, caused by faulty processing (usually contamination of one solution by another); and age fog, caused by inappropriate storage (too warm, too humid, too long). All show different symptoms, and once the particular category has been identified it is usually easy to determine the cause. But the subsequent rescue of an important image may require many hours of computer time.

— Graham Saxby

Fog represents a sense of being lost and confused-not knowing where one is going. Fog can also symbolize the realm of the unconscious, which one may be exploring or attempting to navigate in a dream. Finally, a fog can obscure things, for good or bad.

1. a colloid system in which the dispersion medium is a gas and the dispersed particles are liquid.
2. regrowth after harvesting of a cereal crop. Called also aftermath, feg.
3. obscuring opacity on an x-ray film.

• basic f. — blackening of an unexposed x-ray film after development.
• f. fever — see atypical interstitial pneumonia.
• x-ray f. — local or general exposure to extraneous radiation, light or chemical action which is additional to the true photographic image. Leads to spoiling of the x-ray image.

• Disasters and Phenomena - fog: thick mist or vapor suspended in lower atmosphere near ground
• Confusion

Dansk (Danish)
1.
n. - tåge, omtågethed
v. tr. - indhylle i tåge, gøre uklar, forvirre
v. intr. - dækkes af tåge

idioms:

• fog bank    tågebanke
• in a fog    i en dis

2.
n. - eftergrøde, vintergræs, mos

Nederlands (Dutch)
mist, verwarring, sluier (op foto), nasleep, schuim (voor vuurbestrijding), donkere sfeer, oorzaak van donkerte, lang gras, met mist/sluier omhullen, besluieren (foto), met mist/sluier bedekt worden, mistsignalen plaatsen, met lang gras laten begroeien, lang gras te eten geven

Français (French)
1.
n. - brouillard, confusion, (Météo) brouillard, (fig) brouillard, (Phot) voile
v. tr. - voiler (un film), embrumer, embuer (littér), brouiller, embrouiller, noyer le poisson
v. intr. - embuer, voiler, s'embuer, (Phot) se voiler

idioms:

• fog bank    banc de brume
• in a fog    dans le brouillard

2.
n. - repousse de l'herbe (sur un champ pâturé ou tondu), hautes herbes sèches (qui subsistent après la saison des pâturages)

Deutsch (German)
1.
n. - Nebel
v. - vernebeln, beschlagen

idioms:

• fog bank    Nebelbank
• in a fog    bei Nebel

2.
n. - Verwirrung

Ελληνική (Greek)
n. - ομίχλη, καταχνιά, θολούρα
v. - θολώνω, περιπλέκω, σκεπάζω με ομίχλη, συγχύζω

idioms:

• fog bank    (μετεωρ.) μέτωπο ή μάζα ομίχλης
• in a fog    είμαι ανίδεος, είμαι στο σκοτάδι

Italiano (Italian)
nebbia

idioms:

• fog bank    banco di nebbia

Português (Portuguese)
n. - nevoeiro (m)
v. - enevoar(-se)

idioms:

• fog bank    banco (m) de nevoeiro
• in a fog    confuso ou perplexo

Русский (Russian)
туман, затуманивать

idioms:

• fog bank    полоса морского тумана
• in a fog    в тумане, потеряться, в растерянности

Español (Spanish)
1.
n. - bruma, niebla, neblina
v. tr. - envolver en niebla, empañar
v. intr. - ponerse brumoso, hacerse confuso

idioms:

• fog bank    banco de niebla, niebla espesa
• in a fog    en un mar de confusiones, no saber que hacer

2.
n. - crecimiento del pasto después de la cosecha, musgo

Svenska (Swedish)
n. - efterslåtter, vintergräs, mossa (skotsk), dimma, villrådighet (bildl.)
v. - låta boskap beta av vintergräset, göra dimmig, göra förvirrad (bildl.), bli suddig (foto), lägga ut knallsignaler (järnv.)

中文（简体）(Chinese (Simplified))
1. 雾, 烟雾, 尘雾, 雾气, 迷惑, 困惑, 以雾笼罩, 使模糊, 使困惑, 使形成雾翳, 被雾笼罩, 变得模糊

idioms:

• fog bank    雾层
• in a fog    困惑的, 像在雾中的

2. 雾, 烟雾, 尘雾, 雾气, 迷惑, 困惑

中文（繁體）(Chinese (Traditional))
1.
n. - 霧, 煙霧, 塵霧, 霧氣, 迷惑, 困惑

2.
n. - 霧, 煙霧, 塵霧, 霧氣, 迷惑, 困惑
v. tr. - 以霧籠罩, 使模糊, 使困惑, 使形成霧翳
v. intr. - 被霧籠罩, 變得模糊

idioms:

• fog bank    霧層
• in a fog    困惑的, 像在霧中的

한국어 (Korean)
1.
n. - 안개, 연기, 먼지
v. tr. - ~을 안개로 덮다, 어둡게 하다
v. intr. - 안개가 끼다

idioms:

• in a fog    어찌 할 줄을 몰라, 오리무중에

2.
n. - (겨울 벌판에 있는) 마른 풀

日本語 (Japanese)
n. - 霧, 曇り, 濃霧, 当惑
v. - 霧で覆う, 曇らせる, 混乱させる

idioms:

• fog bank    霧峰
• in a fog    途方に暮れて, 五里霧中で

العربيه (Arabic)
‏(الاسم) ضباب (فعل) بشوش‏

עברית (Hebrew)
n. - ‮ערפל, כתם (בסרט)‬
v. tr. - ‮טישטש, כיסה בערפל‬
v. intr. - ‮התערפל, היטשטש‬
n. - ‮גדילת עשב לאחר קיצוצו, עשב גבוה שהושאר בשדות בחורף‬