A New Look at the Vertical Shear of the Geostrophic Wind. Part II: Thermal Wind and Moist Wind

Document Type : Original Research Article


Faculty member of ASMERC (Retired), Tehran, Iran


We can divide atmosphere into two mediums, barotropic and baroclinic. Due to horizontal gradient of density, baroclinic medium causes to produce various horizontal gradient of pressure with respect to height and implies various horizontal velocities at different layers of the atmosphere. Therefore; geostrophic wind varies with respect to height in this medium.

The horizontal gradient of density not only would produce by horizontal gradient of temperature, but also by horizontal gradient of humidity or combination of both.

If horizontal gradient of density would be by both horizontal gradient of temperature and horizontal gradient of humidity – as they are existing in natural air – in the case; vectorial difference of geostrophic wind with respect to height is; dense wind.

If horizontal gradient of density is related to gradient of temperature solely; vectorial difference between geostrophic wind from top level and bottom level of the layer is; thermal wind.

And if horizontal gradient of density is solely related to gradient of specific humidity; vectorial difference between geostrophic wind from top level and bottom level of the layer is; moist wind.

The purpose of this paper is confirmation of three versions of dense wind, introduction five particular types of thermal wind and present two prominent types of moist wind in natural medium of air. Formulae related to each type are derived and every one of them, represents effects of one type of variation of geostrophic wind with respect to height.


Main Subjects

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