An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

A prefix meaning → pressure used in the formation of compound words, such as → baroclinic, → barometer, → barotropic.

Baro- combining form of Gk. baros "weight;" cognate with Pers. bâr "weight," gerân "heavy;" cf. Skt. guru, L. gravis; PIE *gwere- "heavy;" L. brutus "heavy, dull, stupid, brutish;" Skt. bhara- "burden, load," bharati "he carries;" PIE *bher- "carry, give birth."

Fešâr-, → pressure.

Of, pertaining to, or characterized by → baroclinicity. Sometimes called → barocline.

→ baro-; → -cline; → -ic.

1) A type of instability occurring within a rapidly → rotating star where non-axisymmetric motions can separate surfaces of constant pressure from → equipotential surfaces.
2) A hydrodynamic instability associated with a baroclinic layer of the atmosphere. It arises from temperature variation along the pressure surfaces. Baroclinic instability is associated with the vertical → shear of the mean flow, which is related to the horizontal temperature gradient by the thermal wind equation. Instabilities in a baroclinic region grow by converting potential energy associated with the mean horizontal temperature gradient into kinetic energy through ascending warm air and descending cold air (Rasmussen & Turner (eds.), Polar Lows, Cambridge Univ. Press, 2003).

→ baroclinic; → instability.

The state of stratification in a fluid in which surfaces of constant pressure do not coincide with those of constant density, but intersect. Where baroclinicity is zero, the fluid is → barotropic. Same as baroclinity.

→ baroclinic; → -ity.

Instrument for measuring the atmospheric pressure. It is used in determining height above sea level and predicting changes in weather.

→ baro- + → -meter.

A law which describes the vertical pressure distribution in the lower parts of Earth's atmosphere. The atmospheric pressure decreases exponentially from any reference surface as the altitude increases.

→ barometer; → law.

In a fluid, conditions where surfaces of constant pressure are parallel to surfaces of constant temperature. This state is equivalent to zero → baroclinicity.

→ baro-; → -tropic.

A gas whose density is a function solely of pressure.

→ barotropic; → gas.

A hydrodynamical instability that arises when the horizontal → shear gradient becomes very large. Barotropic instabilities grow by extracting kinetic energy from the mean flow field.

→ barotropic; → instability.

A state of a fluid in which the surfaces of constant density coincide with surfaces of constant pressure (isobaric).

→ barotropic gas.