The aim. The aim of the research in this paper is to determine the components of zenith tropospheric delay for different stations in Ukraine and comparing them with each other. Method. When determination the tropospheric delay it is obtained as a sum of dry and wet components. Calculations of components of zenith troposphere delay were implemented by integral method using data upper-air sounding of atmosphere. Since the dry component is more predictable, an important task was to determine the impact of wet part on the total amendment, whereas the wet component is largely dependent on weather changes. Results. For calculation of the components of tropospheric delay there were used data of upper-air sounding of atmosphere received on the territory of Ukraine, in particular on meteorological stations of Lviv, Kiev, Odessa and Kharkiv during 2015 year. These data were supplemented to the upper limit of the neutral atmosphere with the data the Standard Model of the atmosphere (CMA-81). On the base of the received atmospheric profiles there were made the calculations of dry and wet components of zenith tropospheric delay. Using results of calculations diagrams of changes of dry and wet components were obtained that gives possibility to compare features and character of these changes during the year period at various stations. Scientific novelty. Currently, the researches of change of tropospheric delay in GNSS measurements results is actual because it is related to the issue of more accurate account of the impact of troposphere on satellite measurements, and therefore with increasing of accuracy of determination of points coordinates on the Earth's surface. The actuality of the issue lies in the fact, that today there has not been yet formulated a holistic approach taking into account regional climatic peculiarities or conditions of the troposphere and their corresponding when calculating the value of delay. The practical significance. Obtained results can be used further for creation of regional models of change of troposphere delays, and to predict the impact of troposphere on the GNSS measurements. The diagrams of change of values of zenith tropospheric delay gave the opportunity to evaluate its change during the year period and to compare the values on different stations.
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