The Stokes vector components and the degree of linear polarization of light reflected from the air-water interface contain information about the roughness of the ocean surface, which is correlated with the wave slope statistics and may be used to retrieve it using the Polarization Slope Sensing (PSS) method (Zappa et al., 2008). This statistic is a part of the radiative transfer simulations in the atmospheric correction of the ocean color satellites and other applications. A modification of the method, which minimizes the impact of upwelling light on polarimetric measurements of the reflected light was applied by using Teledyne DALSA camera equipped with a Sony sensor, where each of 1232x1028 pixels had four subpixels with 0-, 90-, 45- and 135-degrees orientation of polarization. In addition, a filter wheel with several color filters was installed in front of the camera, allowing to measure wave slope characteristics at several spectral bands. Shipborne measurements during VIIRS Cal/Val cruises in the Gulf of Mexico and in Hawaii and from a helicopter at several heights during the CCNY cruise in the Chesapeake Bay showed the advantage of the proposed modified polarimetric slope sensing technique. Measured variances of the wave slopes were mostly in the range predicted by Cox-Munk relationships with corresponding standard deviations.
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