The impact of VIIRS polarization sensitivity on ocean color

The sensitivity to polarized radiance input of the VIIRS instrument (Flight Unit 1 on NPP) has been extensively characterized and shown to be compliant with the sensor specifications [1]. We have rigorously modeled VIIRS measurements of polarized, top-of-atmosphere radiances, using Global Synthetic Data in open ocean regions and a VIIRS sensor model incorporating the polarization sensitivity and other sensor characterization data from thermal vacuum chamber tests. An atmospheric correction over ocean (ACO) algorithm is employed to retrieve the water-leaving radiances, L_w. Analysis of L_w retrieval performance indicates that the impact of polarization on relative errors is significant before any correction and is greatly reduced after the demonstrated correction for effects of polarization. The uncertainty in characterization of VIIRS polarization sensitivity induces errors in retrieved L_w in open oceans that are much smaller than the other errors, which are attributable to the inherent ACO algorithm errors and other sensor errors.