Back to: "F"
fog
- Definição1
- Suspension of very small, usually microscopic water droplets in the air, generally reducing the horizontal visibility at the Earth's surface to less than 1 km.
- Fonte1
- WORLD METEOROLOGICAL ORGANIZATION. International Meteorological vocabulary. 2nd ed. Geneva, 1992. (WMO, n.182). Disponível em: < https://library.wmo.int/index.php?lvl=notice_display&id=220#.XeauGOhKiUk >. Acesso em: 22 mar. 2022.
- Definição2
- The meteorological condition in which the horizontal visibility at the earth’s surface is less than 1000 m because of suspended small droplets or ice crystals in the air. Relative humidity in this case is generally 100% but not less than 95%. Fog is formed by the cooling of the air by contact and mixing or, occasionally, through saturation of the air by increasing water content.
- Fonte2
- KUMAR, Bharat (ed.). An illustrated dictionary of aviation. New York: McGraw-Hill, c2005. 752 p.
- Fonte3
- AMERICAN METEOROLOGICAL SOCIETY. Glossary of meteorology. [S.l., última modificação 05 oct. 2015]. Disponível em: < http://glossary.ametsoc.org/wiki/Main_Page >. Acesso em: 22 mar. 2022.
- Fonte4
- INTERNATIONAL CIVIL AVIATION ORGANIZATION. Manual of runway visual range observing and reporting practices. 3rd. ed. Montreal, 2005. (Doc. 9328 AN/908).
- Nota adicional1
- Acronym in English: FG.
- Nota adicional2
- According to U.S. weather observing practice, fog that hides less than 0.6 of the sky is called ground fog. If fog is so shallow that it is not an obstruction to vision at a height of 6 ft above the surface, it is called simply shallow fog. In aviation weather observations fog is encoded F, and ground fog GF.
- Nota adicional3
- Fog is easily distinguished from haze by its higher relative humidity and gray color. Haze does not contain activated droplets larger than the critical size according to Köhler theory.
- Nota adicional4
- Fog (FG) is forecast when the visibility is expected to be less than 5/8 mile.
- Contexto
- The humidity rise is always very rapid and starts from the lowest levels in the case of a dense sea fog. Fog associated with a frontal warm advection causes the humidity to rise first at upper levels.
- Mist and fog are, in many parts of the world, the primary causes for visibility restrictions of operational significance.
- Vicinity of the aerodrome (followed by FG = fog, FC = funnel cloud, SH = shower, PO = dust/sand whirls, BLDU = blowing dust, BLSA = blowing sand, BLSN = blowing snow, DS = duststorm, SS = sandstorm, TS = thunderstorm or VA = volcanic ash, e.g. VCFG = vicinity fog)
- Subárea1
- Meteorology
- Related Term
- haze
- mist
- Português
- nevoeiro