An acquisition system was developed to measure the above water polarized radiance. This system consists of one irradiance sensor for downwelling irradiance, one radiance sensor oriented at 40° from the zenith to measure sky radiance and three radiance sensors looking down at 40° from the nadir to measure above water radiance. In order to obtain the polarized radiance, polarizers with orientation of 0°, 90° and 45° respectively were placed in front of the three radiance sensors. The whole system was installed on the bow of the boat for continuous observations of above water polarized radiance along the ship's track during a recent cruise in the NY Bight area. Water optical properties were measured by an optical package towed from a small R/V. In order to obtain the degree of polarization (DOP) of the water body, the contribution of the sky radiance must be first removed and this process has to be done for all components of the Stokes vector. Using a model employing the polarized Fresnel coefficients of the interface the polarized component of reflection is estimated from the direct measurement of sky radiance and downwelling irradiance data. These components are then subtracted from the measured values to obtain the water contribution. The DOP of the ocean body is then related to the in - water IOPs.
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