All meteorological and oceanographic textbooks unintentionally define the Earth gravitation outside the solid Earth through treating the Earth as a point-mass located at the Earth center containing the entire Earth mass or assuming the Earth with uniform mass density. Combination of such simplified gravitational and centrifugal accelerations leads to the effective gravity geff. The geopotential surface corresponding to geff (called the effective geopotential surface) is the ellipsoidal surface. The true Earth gravitation outside the solid Earth is the volume integration of gravitation of all point-masses inside the Earth. Combination of true gravitational and centrifugal accelerations leads to the true gravity g. The geopotential surface corresponding to g (called the true geopotential surface) and respect to the Earth ellipsoidal reference surface is the geoid, which varies approximately from -106 m to 86 m worldwide. The true gravity g minus the effective gravity geff is the gravity disturbance vector, δg = g – geff, which is a major variable in geodesy and solid Earth dynamics. Contrarily, δg is neglected completely in dynamics of atmosphere and ocean. In this study, the true gravity g replaces the effective gravity geff in atmospheric dynamic equations. Seven non-dimensional numbers are proposed to identify the magnitude of horizontal gravity disturbance vector (δg)⊥versus traditional horizontal forcing terms such as pressure gradient force and Coriolis force. These non-dimensional numbers are calculated from two publicly available and independent datasets with the geoid undulation (N) from the static gravity field model EIGEN-6C4 and long-term mean geopotential height (Z), wind velocity (u, v), and temperature (T) at 12 pressure levels in troposphere from the NCEP/NCAR reanalyzed climatology. The results demonstrate (δg)⊥ nonnegligible in hydrostatic equilibrium, geostrophic wind, geostrophic vorticity, Q vector, and Omega equation.