GMD Perspective : the quest to improve the 1 evaluation of groundwater representation in 2 continental to global scale models 3 4

ions Crucial for groundwater depletion and sustainability studies National scale data highly variable in quality; downscaling uncertain de Graaf et al. 2014 Döll et al. 2014 National-scale data down-scaled to grid Streamflow or spring flow observations Widely available at various scales; low flows can be related to groundwater Challenging to quantify the flows between groundwater and surface water from streamflow Global Runoff Data Centre (GRDC) or other data sources; large to small basin; Olarinoye et al. 2020 point measurements of spring flow https://doi.org/10.5194/gmd-2021-97 Preprint. Discussion started: 20 April 2021 c © Author(s) 2021. CC BY 4.0 License.