Refraction in bilateral trigonometric leveling. Defi nition of corrections

Abstract

The practical application of bilateral trigonometric leveling in geodetic measurements is limited by the effect of atmospheric refraction. If this effect is eliminated, the accuracy of bilateral measurements can be comparable to the results of precise geometric leveling. By applying the similarity and modeling method to the problem of accounting for refraction in leveling and also taking into account the conditions of interaction of the optical beam with the physical processes taking place in the surface layer, these limitations can be minimized. The solution of the problem of determining corrections due to the influence of refraction in bilateral trigonometric leveling by simulation of the quantities participating in the process, obtained through joint geodetic and meteorological measurements, as well as the main provisions – in unilateral leveling, which are the basis for the method of bilateral measurements. Practical examples show the features of calculation of corrections, depending on the state of thermal stratification of the surface layer of the atmosphere.