Suspended solids analysis using ERTS-A data

The magnetic digital tapes of the imagery obtained by ERTS-A on September 23, 1972, have been analyzed for selected areas of the Potomac River. A statistical analysis of all four bands has been carried out. The results show that band III is useful in determining the water-to-land interface. Data on bands II suggest the existence of three distinct types of water—those having low, medium, and high reflecti vity. From previously published results and ground truth measurements the areas of hight reflectivity were identified as containg high concentrations of suspended solids. Areas of low reflectivity were identified as having relatively lower concentrations of suspended solids. A commonly used computer technique with some additional refinements has been used to generate thematic maps which identify the above areas and show their geographical distribution.