Fig. 2: Groundwater recharge volumes and trends.
From: Living within the safe and just Earth system boundaries for blue water
a, Average annual groundwater recharge volume derived from GRACE59, representing the safe and just volume of groundwater that can be drawn down annually (including natural groundwater discharge and anthropogenic extraction). b, The trend in annual recharge volume between 2003 and 2016, showing where annual recharge is declining (red areas) or increasing (blue areas). Grey hatching in b shows where there has been an associated decline in annual rainfall. Light grey hatching shows regions where declines have been below the 10th percentile (<5.5 mm yr−1) while darker grey hatching shows where declines in rainfall have been above this threshold.
