Summer Land-Atmosphere Coupling over Europe: A Comparative Evaluation of Observation-based Datasets

Abstract. Land–atmosphere coupling has long been recognized to modulate the surface fluxes partitioning in transitional evaporative regimes, where soil moisture anomalies control evapotranspiration. However, globally available in-situ observations for these variables remain limited. This study provides a comprehensive assessment of the similarities, dissimilarities, and limitations among gridded observations-based datasets of surface soil moisture, evapotranspiration, potential evapotranspiration, and 2-meter air temperature across Europe. The analysis focuses on the IPCC-defined regions of Northern Europe, Eastern Europe, Western-Central Europe, and the Mediterranean during summer (June–August) for the recent 20-year period (2003–2022), and evaluates and compares the representation of land–atmosphere coupling across the different datasets. Results show that the temporal variation of the state variables and the spatial variability of land–atmosphere coupling are mostly consistent across the different datasets. On the other hand, relevant differences in absolute values and seasonal variations can be identified. Some datasets exhibit systematically distinct annual cycle patterns compared to others across variables and regions, which is also reflected in their coupling representation in both temporal and spatial structures.