A dataset of long daily TWS changes over Europe, inferred from vertical displacements measured by GPS

Vertical displacements of Earth’s crust recorded by a set of permanent stations of Global Positioning System (GPS) antennas are used to infer the gridded changes in Terrestrial Water Storage (TWS) using elastic loading theory. Spatial resolution of the resulting gridded TWS changes is dependent on the number of displacement observations available for the region. For several regions around the world, including Europe, dense networks of GPS stations may guarantee high spatial resolution of the inferred gridded TWS changes, far exceeding the spatial resolution of gridded TWS changes that can be obtained from the Gravity Recovery and Climate Experiment (GRACE) observations. Similarly, the daily temporal resolution of gridded TWS changes that we can infer using daily GPS displacements is extremely competitive with monthly GRACE solutions. Both improvements allow for the analysis of regional sub-monthly TWS changes. In this presentation, we showcase a dataset of daily gridded TWS changes over Europe, inferred from vertical displacements measured by more than 4,000 GPS stations across Europe, for a period of 1994-2023. We use the vertical displacements provided by the Nevada Geodetic Laboratory (NGL) and analyze them thoroughly to eliminate the displacements showing apparent changes unrelated to hydrology. We then divide the displacements into three temporal scales of short-term, seasonal and long-term changes to enhance a better understanding of the resulting gridded TWS changes and classify this set of GPS stations into hydrological benchmarks. We then use this benchmark dataset and invert the displacement time series into gridded TWS changes over Europe. We perform several comparisons on regional and local spatial scales with GRACE, hydrological models, and other datasets, and prove that the resulting TWS changes may enhance future analyses of regional hydrological changes.