# Moisture-continuity equation

From AMS Glossary

## moisture-continuity equation

The water vapor storage equation as applied to the atmosphere.

The general form of the equation is written where

*I*is the atmospheric moisture inflow,*E*the evapotranspiration from the ground,*O*the atmospheric moisture outflow,*P*precipitation, and*dS*/*dt*the time rate of change of moisture storage in the portion of the atmosphere under consideration. In practice the equation is more commonly applied to a finite interval of time and the various terms become mean values in this interval.