Fig. 4
(a) Locations of groundwater observation wells at which data are published in the literature. Red and blue colors indicate declining and increasing trends, respectively, in annual groundwater, whereas the grey color indicates either no significant change or groundwater data are available for less than 5 years. We used Mann-Kendall with Sen Slope method to calculate the trend. The time period of available datasets along with trend significance is provided in Table S1, (b) daily discrete groundwater depth at 5 locations in Laos from 01-Oct-2011 to 31-Oct-2012, digitized from Vote et al.155, (c) yearly groundwater depth at 7 locations in Thailand from 2004 to 2020, digitized from Muenratch et al.55, (d) daily discrete GW depth from 1996 to 2008 at 2 locations in Cambodia, digitized from Johnston et al.142, and (e) monthly GW depth from 1991–2015 at 7 location in Mekong Delta, Vietnam, digitized from Minderhoud et al.46.
