Flow depths were measured using Laser-induced fluorescence (LIF) (Sue et al., 2006). Fluorescent dye was added to the water, with a concentration of approximately 0.1 mg/l and illuminated by the Nd-YAG Laser. The emitted light from the fluorescent dye was recorded by a Kodak Megaplus ES1.0 b/w digital video camera fitted with a 50 mm fixed focal length lens and a Hasselblad orange filter. The camera was aligned with the 1:10 slope of the beach and rotated forwards so that the camera view was at all times above the free surface (Fig. 4).
water
Fluorescent dye
approximately 0.1 mg/l
mg/l
lens
fixed focal length
50 mm
mm
beach
slope
1:10