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The main goal of this study is to develop and test an algorithm for determining the moment of inertia and angular momentum of a tectonic plate based on the processing of time series of daily solutions of continuous GNSS (Global Navigation Satellite System) stations. The proposed algorithm consists of four consecutive stages: reformatting data to the internal format; dividing the plate into cells and determining their masses; determining the rotation poles and distances from cells to the poles; calculating the plate’s moment of inertia and angular momentum. The algorithm uses freely available time series of daily solutions from continuous GNSS stations or any other data prepared in a similar format. The algorithm is tested for determining the moment of inertia and angular momentum of the Antarctic plate based on the processing of time series of daily solutions of continuous GNSS stations for the period 1995–2021. It is confirmed that the Antarctic Plate’s rotation poles, moment of inertia, and angular momentum are dynamic parameters. However, additional calculations and in-depth comprehensive analysis are required to determine the causes of such dynamics. As a result of comparing, the dynamics of changes in the Antarctic Plate’s rotation poles partially compensate for the unevenness of the Earth's rotation to keep the angular momentum of the Earth constant.

The aim of this study is modeling the dependence of maximum velocity of the Trooz Glacier (Kyiv Peninsula, West Antarctica) on air temperature. For this purpose, we processed a time series of meteorological observations at the Akademik Vernadsky station and the ice flow velocity of the Trooz Glacier. The ice velocities were determined from the synthetic aperture radar images, acquired by the Sentinel-1 satellite, for the period from May 2015 to November 2022. The SAR images were processed in the SNAP (Sentinel Application Platform) program using the Offset Tracking method. As a result, 219 ice flow velocity maps were obtained. During the studied period, the maximum velocities varied from 2.64 m/day (August 19, 2015) to 4.05 m/day (April 18, 2020). A functional dependence between the temperature data from the Akademik Vernadsky station and the remotesensing data on the air temperature above the glacier’s surface was established. We combined the three parameters (time series of the maximum velocities of the glacial flow, remote temperature measurements above the glacier, and direct temperature measurements at the Akademik Vernadsky station) in a linear model. In order to increase the accuracy of the modeling, an a posteriori optimization was carried out. As a result, the average error in determining the maximum velocity of the glacier reduced from 23 cm/day to 17 cm/day.

The main purpose of this work is to study and analyze the coordinate time series of the first Ukrainian permanent Global Navigation Satellite System (GNSS) station in Antarctica — Antarctic Station Academic Vernadsky (ASAV). We also aimed to do a comprehensive study of geophysical factors on the coordinate time series values and determine the values of the displacement components of this GNSS station. Processing of measurements was performed using the software Bernese GNSS Software v.5.2. The Bernese Processing Engine (BPE) module and the RNX2SNX (RINEX-TO-SINEX) processing algorithm were used to obtain daily solutions of permanent GNSS station ASAV. Daily solutions of the permanent GNSS station ASAV and the vector of its displacements were determined in the coordinate system IGb08. The vector of the permanent GNSS station ASAV has a northeasterly direction. The obtained results are consistent with the model of tectonic plate movements of this region. To study the characteristic periods of harmonic oscillations of coordinate time series of permanent GNSS station ASAV due to various geophysical factors. A set of studies was conducted, which included the development of an algorithm and a package of applications for processing time series and determining optimal curves that most accurately describe them. Thus, for each time series, the original equation is used to determine the optimal period of oscillation. As a result, an anomalous distribution of fluctuations in the values of permanent GNSS station ASAV with different periods was revealed — this indicates the complex nature of the influence of geophysical factors on the spatial location and confirms the need for systematic studies of such factors on the stability and displacement of GNSS station. It is established that the permanent GNSS station ASAV is exposed to seasonal oscillations, associated with changes in environmental conditions.