Surface roughness and wave slope statistics from the multi-spectral polarimetric imaging of the ocean surface

Abstract

The polarization of light in Ocean Color (OC) applications provides important information about atmospheric parameters, water composition, and the ocean surface. The Stokes vector components and the degree of linear polarization of light contain useful information about the air-water interface, including ocean surface roughness. We present polarimetric measurements and analysis of the ocean wave slopes at several bands. Data is acquired with a Teledyne DALSA camera, which uses a polarizer-on-chip focal plane of 1232 × 1028 super-pixels, where each pixel is made of four subpixels with 0-, 90-, 45- and 135-degrees orientation of polarization. We present a modified version of the Polarization Slope Sensing (PSS) technique [Zappa et al., 2008] for the non-contact detection of wave slopes and demonstrate a good performance of the updated algorithm in several conditions where the original technique was not applicable. Derived wave slopes are presented for various aquatic and atmospheric environments, including during VIIRS Cal/Val cruises and at a near-shore pier. The results are shown to be consistent with theoretical wave slope models.