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The intensity and location of Sun glint in two Medium Resolution Imaging Spectrometer (MERIS) images was modeled using a radiative transfer model that includes elevation features as well as the slope of the sea surface. The results are compared to estimates made using glint flagging and correction approaches used within standard atmospheric correction processing code. The model estimate gives a glint pattern with a similar width but lower peak level than any current method, or than that estimated by a radiative transfer model with surfaces that include slope but not height. The MERIS third reprocessing recently adopted a new slope statistics model for Sun glint correction; the results show that this model is an outlier with respect to both the elevation model and other slope statistics models and we recommend that its adoption should be reviewed.

A fast graphics processing unit implementation of the finite-difference time-domain model was used to determine the computational effort required to accurately characterize the mean scattering functions of randomly orientated aspherical particles. The influence of the number of randomized rotational positions on the accuracy of the mean scattering phase function curve was appraised. In general, multiplying the number of orientations by 100 gives increased accuracy of factor 10. Dependent on particle shape, certain regions of the phase function were insensitive to particle orientation. In addition, an error in a key previous publication on scattering by aspherical particles was identified.