Estimation of propagation path delay

Dry air, water vapor, hydrometeors, and other particulates (sand, dust, aerosols) in the atmosphere introduce microwave propagation delays. These delays must be properly characterized to achieve the highest accuracy in Geodetic survey. This work examines the dependence of the meteorological parameters in determining propagation delay. It is found that variation of water vapor density with height in addition to temperature variation plays a critical role. It is shown that temperature lapse rate and wet adiabatic lapse rate play a major role.