In meteorology and physical oceanography, advection often refers to the horizontal transport of some property of the atmosphere or ocean, such as heat, humidity or salinity, and convection generally refers to vertical transport (vertical advection). Because of the specific use of the term convection to indicate transport in association with thermal gradients, it is probably safer to use the term advection if one is uncertain about which terminology best describes their particular system. Thus, although it might seem confusing, it is technically correct to think of momentum being advected by the velocity field in the Navier-Stokes equations, although the resulting motion would be considered to be convection. More technically, convection applies to the movement of a fluid (often due to density gradients created by thermal gradients), whereas advection is the movement of some material by the velocity of the fluid. The term advection often serves as a synonym for convection, and this correspondence of terms is used in the literature. In meteorology and physical oceanography, advection often refers to the transport of some property of the atmosphere or ocean, such as heat, humidity (see moisture) or salinity.Īdvection is important for the formation of orographic clouds and the precipitation of water from clouds, as part of the hydrological cycle.ĭistinction between advection and convection It does not include transport of substances by molecular diffusion.Īdvection is sometimes confused with the more encompassing process of convection, which is the combination of advective transport and diffusive transport. Advection requires currents in the fluid, and so cannot happen in rigid solids. The fluid's motion is described mathematically as a vector field, and the transported material is described by a scalar field showing its distribution over space. In general, any substance or conserved, extensive quantity can be advected by a fluid that can hold or contain the quantity or substance.ĭuring advection, a fluid transports some conserved quantity or material via bulk motion. Here the fluid may be any material that contains thermal energy, such as water or air. Another commonly advected quantity is energy or enthalpy. An example of advection is the transport of pollutants or silt in a river by bulk water flow downstream. The properties that are carried with the advected substance are conserved properties such as energy. Generally the majority of the advected substance is also a fluid. The properties of that substance are carried with it. In the field of physics, engineering, and earth sciences, advection is the transport of a substance or quantity by bulk motion of a fluid. JSTOR ( May 2022) ( Learn how and when to remove this template message).Unsourced material may be challenged and removed. Please help improve this article by adding citations to reliable sources. deur mis vasgekeer deur mis vertraag طائِرَه غير قادِره على الطيران بسبب الضباب задържан от мъгла preso pelo nevoeiro uvázlý v mlze durch Nebel behindert opholdt på grund af tåge ακινητοποιημένος λόγω ομίχλης inmovilizado por la niebla uduvangis گرفتار در مه sumussa pris dans la brume תְּקוּע בִגלָל הַעֲרָפֶל कोहरे से हुई परेशानी zaustavljen (nepokretan) zbog magle ködben veszteglő terhambat kabut tepptur vegna þoku fermo 霧に閉じこめられた 안개에 쌓인 negalintis skristi/plaukti dėl rūko miglas aizkavēts penuh kabus door mist opgehouden fast/innstilt pga.This article needs additional citations for verification. Unable to move or function because of fog. Wreaths of white fog walked like ghosts in the haunted meadow -John Greenleaf Whittier.There’s a fog at the waists of the trees, like a sash -William Matthews.Puffs of white fog which hung there like frozen cabbage -Donald McCaig.Night fog thick as terry cloth -Maxine Kumin.
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