DETERMINATION OF SUSPENDED SEDIMENT CONCENTRATIONS FROM CZCS DATA

About one hundred images of the southeastern Mediterranean coastal wat ers, which were produced by the NimBus-7 CZCS, have been used to study the circulation pattern of the region. This paper is aimed (1) to ada pt and calibrate an optical model for determining suspended sediment c oncentrations for the study area; and (2) to demonstrate the applicati on of an interpolation technique for creating a continuous spectrum fr om a small number of multispectral image channels. The study area is c haracterized by relatively high suspended sediments and very low chlor ophyll concentrations. The optical model which was found to be suitabl e for estimating suspended sediment concentrations (C(sm)) from the cz cs data has the form of C(sm) = 1. 4 + 1.6([Lu(550) -Lu(670)]1.7/[Lu(4 40)/Lu(550)]), where Lu is the upwelling radiance for the various wave lengths. This model meets the fundamental requirements of low sensitiv ity to both chlorophyll and atmospheric variation remaining after corr ection. A method of estimating the continuous spectrum, based on a sma ll number of multispectral image channels, along a transect crossing a front of optical density variation was developed. The spectral featur es of the water reflectance were analyzed. Results show that this meth od enables one to determine, with adequate sensitivity, the parameters of water quality of the region.