Figure 5.
e-vector orientation versus absolute solar zenith angle (SZA = θs) measured in clear waters at eight azimuthal angles of 8°, 53°, 98°, 143°, 188°, 233°, 278° and 323° defined from the north towards the east. (a,b) Viewing zenith angle (VZA = θp) = 30° and 70°, respectively, at 2 m depth (sea-floor depth = 6 m), and (c) VZA = 90° at 5 m depth (sea-floor depth = 28 m). The red line represents the horizon, the green lines represent angle of refraction into the water (for real refractive index = 1.337, wavelength = 450 nm), and the blue lines represent the margins of Snell's window ± 48.4°. Measurements at VZA = 90° at 2 m depth are not presented, as they exhibit negligible differences from the measurements at 5 m depth.