Estimation of lunisolar correction in precise levelling

Abstract

Under the effect of the celestial bodies the deflection of vertical induces changes in the levelled height difference. It is necessary to evaluate this effect in highprecision levelling data. The largest impact is due celestial bodies closest to the Earth - the Moon and the Sun. Revised formulas for calculating lunisolar correction derived by using tide generating potential. Dependency of lunisolar correction from lunar phase, azimuth of the levelling line and correction rate of change was analysed. The analysis could be used to improve the estimation of celestial bodies’ effect on height difference determined by geometric levelling.