Prognose der oberflächennahen Grundwassertemperatur in Sachsen-Anhalt

Information on groundwater temperature (GWT) is often sparse and only available as point data from monitoring wells. For large-scale spatially distributed estimates of GWT, satellite data are a suitable complement to conventional interpolation. This method utilizes the thermal coupling between land surface and the shallow subsurface. In this study, the distribution of GWT in Saxony-Anhalt is characterized. Based on remote sensing data and measurements from 436 wells, the GWT field is estimated with a spatial resolution of 500 m. In addition to the GWT and the land surface temperature, further variables are used, which influence the GWT and thus increase the accuracy of the estimation. Compared to previous studies, the results show the highest resolution and accuracy (RMSE = 0.74 K) for current GWT estimates. The methodology produces good results for all land cover classes (RMSE = 0.55 − 1 K). However, outliers show that a higher resolution is needed to detect local hotspots more reliably.