The atmospheric geoid effects in Stokes' formula

The application of Stokes' formula requires that the atmospheric effect on the gravity anomaly is removed. We show that this direct effect reaches abo ut -40 cm over the Himalayas and Antarctica. The restoring of the atmospher ic masses yields the indirect atmospheric effect, reaching about -20 cm for the same regions. Consequently, the total atmospheric effect on the geoid is of the order of - 60 cm. However, for most areas close to sea level, the correction is within a few centimetres. Furthermore, the total atmospheric geoid effect is derived for the truncated as well as the modified Stokes f ormula. It is emphasized that the traditional (IAG) approach to adding a di rect atmospheric effect to gravity may lead to a serious geoid bias in the truncated Stokes formula. However, as all the parameters of the bias are kn own, it can easily be corrected. In contrast, we suggest that the total atm ospheric effect on the geoid be determined separately. In this approach the bias is avoided.