Derived groundwater storage (GWS) measured in water thickness equivalent over the land areas of the Great Lakes Basin using the Center for Space Research (CSR) release 04 (RL04) (top) and GeoForschungsZentrum (GFZ) release 04 (RL04) (bottom) Gravity Recovery and Climate Experiment (GRACE) models. Each model incorporates three soil moisture, snow, and lake (SMSL) water storage fields that have different land-surface models.
