Accuracy Analysis of the Heights in Reference Networks in Bosnia and Herzegovina

Abstract

Modern Satellite geodesy methods allows the collection of geospatial information with high accuracy and resolutions that were not imaginable half a century ago. Thus, Global Navigation Satellite Systems ensure the point positioning with 3D accuracy below 1 cm, globally. On the other hand, satellite gravimetric missions have made global mapping of the Earth’s gravity field, with incomparable accuracy and resolution. A large number of global geopotential models are estimated from the collected geospatial data. Traditional geodetic methods used in the 19th and 20th centuries, such as the trigonometric networks, determined the point positions and heights applying optical method, with planned positioning accuracy of 10 cm. A classic terrestrial method of precise leveling still has unprecedented accuracy of 1–2 mm/km, but this method is expensive and time-consuming. The availability of precise modern data made it possible to analyze the accuracy of the conventional terrestrial methods. This paper is inspired by previous research, which showed that in the trigonometric networks of the first and second orders in Bosnia and Herzegovina blunders in trigonometric point’s heights exist. This paper is a result of the research of the accuracy of the height of the trigonometric points of the third and fourth order in network of Bosnia and Herzegovina, which are still in the official use. Based on the points with coordinates available in both, modern global and classical local reference systems, investigation the two Global a Geopotential Models: Earth Gravitational Model - EGM2008 and A High-Resolution Global Gravity Combination Model Including GOCE Data - EIGEN6C presented. Total number of points whose deviations from official ones exceed the threshold of 30 cm is 18, or 4.52% of the total 398 points analyzed.