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Abstract. For nearly 3 decades, geodetic Global Navigation Satellite System (GNSS) measurements in Antarctica have provided direct observations of bedrock displacement, which is linked to various geodynamic processes, including plate motion, post-seismic deformation, and glacial isostatic adjustment (GIA). Previous geodynamic studies in Antarctica, especially those pertaining to GIA, have been constrained by the limited availability of GNSS data. This is due to the fact that GNSS data are collected by a wide range of institutions and network operators, with the raw observational data either not publicly available or scattered across various repositories. Further, the metadata necessary for rigorous data processing have often not been available or reliable. Consequently, the potential of GNSS observations for geodynamic studies in Antarctica has not been fully exploited yet. Here, we present consistently processed coordinate time series for GNSS sites in Antarctica and the sub-Antarctic region for the time span from 1995 to 2021. The data set is composed of 286 continuous and episodic sites, with 258 sites having a time span longer than 3 years. The coordinate time series were obtained from a combination of four independent processing solutions using different GNSS software and products, allowing the identification of inconsistencies in individual solutions. From these, we infer a reliable and robust combined solution. A key issue was the thorough reassessment of station metadata to minimise artefacts and biases in the coordinate time series. The resulting data set provides coordinate time series with unprecedented spatiotemporal coverage, promising significant advancements in future geodynamic studies in Antarctica. The data set is freely available at https://doi.org/10.1594/PANGAEA.967515 (Buchta et al., 2024a). 

Abstract The Patagonia Icefields (PIF) are the largest non-polar ice mass in the southern hemisphere. The icefields cover an area of approximately 16,500 km 2 and are divided into the northern and southern icefields, which are ~ 4000 km 2 and ~ 12,500 km 2 , respectively. While both icefields have been losing mass rapidly, their responsiveness to various climate drivers, such as the El Niño-Southern Oscillation, is not well understood. Using the elastic response of the earth to loading changes and continuous GPS data we separated and estimated ice mass changes observed during the strong El Niño that started in 2015 from the complex hydrological interactions occurring around the PIF. During this single event, our mass balance estimates show that the northern icefield lost ~ 28 Gt of mass while the southern icefield lost ~ 12 Gt. This is the largest ice loss event in the PIF observed to date using geodetic data.