Figure 3.

(a) Pore-water salinity measured during June 9^th at four depths (0–0.05 m, 0.05–0.1 m, 0.1 m–0.15 m, and 0.15 m–0.2 m) at PW1 location along with the measurements of tide and groundwater table. (b) Observed salinity profile at the top 5 cm layer of the beach at different times. Two values 160 g/l and 220 g/l are not reported in the figure for visual clarity. They contributed to the average value. (c) Simulated salinity contour at 11:30 AM on May 19^th. White dashed lines denote moisture content (percentage by volume) and the white solid line denotes groundwater table. The velocity vectors indicate only the pore-water velocity direction, but not its magnitude. Also, note that due to the exaggeration of the vertical scale, the velocity vectors do not appear perpendicular to the beach surface (as the beach slope was visually increased). Extremely high pore-water salinity was measured at PW1 at the top 5 cm; in contrast, pore-water salinity at other depths and/or locations was almost the same as seawater (shown in Figure S6). The simulated contour indicates that a high saline layer was formed along the beach surface due to evaporation.