# Barotropic

In

meteorology , a**barotropic**atmosphere is one in which the pressure depends only on the density and vice versa, so that isobaric surfaces (constant pressure surfaces) are alsoisopycnic surfaces (constant density surfaces). The isobaric surfaces will also beisothermal surfaces, hence (from thethermal wind equation ) thegeostrophic wind is independent of height. Hence the motions of a rotating barotropic fluid are strongly constrained.A "barotropic flow" is a generalization of the barotropic atmosphere described above: It is a flow in which the pressure is a function of the density only and vice versa. In other words, it is a flow in which isobaric surfaces are isopycnic surfaces and vice versa. One may have a barotropic flow with a non-barotropic fluid, but a barotropic fluid must always follow a barotropic flow. Examples include barotropic layers of the oceans, an isothermal ideal gas or an

isentropic ideal gas.Barotropic fluids are also important idealized fluids in astrophysics, such as in the study of stellar interiors or of the interstellar medium. One common class of barotropic model used in astrophysics is a polytropic fluid. Typically, the barotropic assumption is not very realistic.

Contrast baroclinic. In particular, for a barotropic fluid or a barotropic flow (such as a barotropic atmosphere), the baroclinic vector is always zero.

**References*** James R Holton, "An introduction to dynamic meteorology", ISBN 0-12-354355-X, 3rd edition, p77.

* Marcel Lesieur, "Turbulence in Fluids: Stochastic and Numerical Modeling", ISBN 0-7923-0645-7, 2e.

* D. J. Tritton, "Physical Fluid Dynamics", ISBN 0-19-854493-6.**See also***

Atmospheric dynamics

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### Look at other dictionaries:

**barotropic**— /bar euh trop ik/, adj. (of a fluid) having a density that is a function only of pressure. [BARO + TROPIC] * * * … Universalium**barotropic**— adjective in which the pressure of the atmosphere is dependent upon its density only … Wiktionary**barotropic**— /bar euh trop ik/, adj. (of a fluid) having a density that is a function only of pressure. [BARO + TROPIC] … Useful english dictionary**Barotropic cyclone**— Barotropic cyclones are those where isotherms are parallel to height lines on a map at a constant pressure surface, or at the surface, parallel to isobars. Tropical cyclones and cut off cyclones (occluded and formerly occluded cyclones) both… … Wikipedia**Barotropic vorticity equation**— A simplified form of the vorticity equation for an inviscid, divergence free flow, the barotropic vorticity equation can simply be stated as:frac{D eta}{D t} = 0,where frac{D}{D t} is the material derivative and:eta = zeta + fis absolute… … Wikipedia**barotropic fluid**— a barotropic fluid is one whose pressure and density are related by an equation of state that does not contain the temperature as a dependent variable. Mathematically, the equation of state can be expressed as p = p(r) or r = r(p) … Mechanics glossary**barotropic effect**— barotropinis reiškinys statusas T sritis fizika atitikmenys: angl. barotropic effect vok. barotropes Phänomen, n rus. баротропическое явление, n; баротропное явление, n pranc. phénomène barotrope, m … Fizikos terminų žodynas**BEMPEX**— Barotropic Electromagnetic and Pressure Experiment (Academic & Science » Ocean Science) … Abbreviations dictionary**fluid**— barotropic fluid compressible fluid incompressible fluid inviscid fluid irrotational fluid laminar fluid non turbulent fluid Newtonian fluid perfect fluid rotational fluid Stokesian fluid … Mechanics glossary**Atmospheric model**— A 96 hour forecast of 850 mbar geopotential height and temperature from the Global Forecast System An atmospheric model is a mathematical model constructed around the full set of primitive dynamical equations which govern atmospheric motions. It… … Wikipedia