The article describes the procedure for transformation between old and new horizontal geodetic datum in Bosnia and Herzegovina. Two triangle-based methods were used for transformation, which are based on irregular and regular triangular network. For development of transformation models two set of points were used, one for developing models (around 1200 points), and other for testing (around 850 points). Prior to development, all points were tested at presence of outliers, and outliers are marked in the points database. Results shows that large part of distortions in old triangulation network can be modeled with used methods. Maximal positional standard deviations with best model are 4.5 and 6.4 cm for two sets of points, respectively, while maximal positional discripencies are 30 and 40 cm for two sets of points. Each method has some advantages and disadvantages which are shown in this article. It is shown that the number, spatial distribution and quality of input data are crucial for development of highly accurate transformation model. Also, as an important contribution of this work, some problematic areas with irregular distortions are identified. Finally, some recommendations are given for improvement of developed models.

Due to its dispersive nature, ionosphere causes a group delay or phase acceleration of the signals from Global navigation satellite systems - GNSS. Despite the progress of GNSS positioning methods, the ionospheric refraction is still one of the greatest source of the errors in the geodetic positioning and navigation. Different phenomenons oft he space weather: solar wind, geomagnetic storm, solar radiation, can damage GNSS, and electric power distribution networks but That is why it's important to establish research and monitoring methods of the space weather. The subject of this paper is the investigation of ionosphere and space weather. Procedure of constructing a SID (engl. Sudden ionospheric disturbances) monitor station are described. The analysis showed that ionosphere monitoring station in Sarajevo, SRJV_ION 0436, was able to detect increased solar radiation.

Troposphere plays crucial role for geodetic comunity, which can primarly be seen in its influence on GNSS observations. At the same time, troposhpere is the place where almost all hidrometeorological phenomena that effect our everyday life occure. Scientists have found a way to use systematic influence that troposphere has on GNSS signal and turn it into meteorological indicator, water vapor quantity. In this paper term of GNSS meteorology is described, as well as its basic classification and application.