Correction of sun glint effect on MIVIS data of the Sicily campaign in July 2000

To assess the suspended and dissolved matter in water in the visible and near infrared spectral regions it is necessary
to estimate with adequate accuracy the water leaving radiance. Consequently radiance measured by a remote
sensor has to be corrected from the atmospheric and the sea surface effects consisting in the path radiance
and the sun and sky glitter radiance contributions. This paper describes the application of the sun glint correction
scheme on to airborne hyperspectral MIVIS measurements acquired on the area of the Straits of Messina
during the campaign in July 2000. In the Messina case study data have been corrected for the atmospheric effects
and for the sun-glitter contribution evaluated following the method proposed by Cox and Munk (1954,
1956). Comparison between glitter contaminated and glitter free data has been made taking into account the radiance
profiles relevant to selected scan lines and the spectra of different pixels belonging to the same scan line
and located out and inside the sun glitter area. The results show that spectra after correction have the same profile
as the contaminated ones, although, at this stage, free glint data have not yet been used in water constituent
retrieval and consequently the reliability of such correction cannot be completely evaluated.

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