Fig. 3: Modern validation of noble gas isotope-derived water table depths.
From: Deglacial water-table decline in Southern California recorded by noble gas isotopes
Water-table depth estimates derived from groundwater noble gas isotope measurements are compared to historical water-level observations near two adjacent wells sampled in March 2018 near Fresno, California. Depths are relative to the land surface. Historical records from within a 10-km radius of the sample site were included, except for those from the highly populated city center, which dropped substantially in the mid-20th century (Supplementary Fig. 4). Multiple age tracers were used to determine probable recharge ages (Supplementary Fig. 5).
