Moisture Flux
In terms of mixing ratio, horizontal transport/advection can be represented in terms moisture flux:
in which q is the mixing ratio. The value can integrated throughout the atmosphere to total transport of moisture through the vertical:
which is the density of air, P is pressure at the ground surface. For the far right definition, we have used Hydrostatic equilibrium approximation.
and its divergence (convergence) imply net evapotranspiration (precipitation) is adding (removing) moisture from the column:
which P, E, and the integral term are precipitation, evapotranspiration, and time rate of change of Precipitable water; all represented in terms of mass per unit area (one can convert to more typical units in length such as mm by multiplying the density of liquid water and the correct length unit conversion factor).
Read more about this topic: Moisture Advection
Famous quotes containing the word flux:
“Existence is no more than the precarious attainment of relevance in an intensely mobile flux of past, present, and future.”
—Susan Sontag (b. 1933)