The word atmosphere is derived from two Greek words, atmos and spheria. Atmos means vapour and spheria means sphere or spherical earth as its extended meaning. Atmosphere, therefore, means the gaseous envelope surrounding the earth.
Hydrometeorology is the study of that atmospheric process, which affects the hydrologic characters of a region.
The permanent constituents of air, in gaseous form, are: (1) nitrogen—78%, (2) oxygen—21% and (3) inert gases 1%. The variable constituents may be in the solid, liquid or gaseous form.
Water is one of these variable constituents, ...