REMOTE SENS. ENVIRON. 45:177-191 (1993) Water Quality Monitoring by Thematic Mapper in Coastal Environments. A Performance Analysis of Local Biooptical Algorithms and Atmospheric Correction Procedures S. Tassatt Institute for Remote Sensing Applications, Commission of the European Communities, Joint Research Centre-Ispra Establishment, Italy M. Ribera d'Alcal6 Biological Oceanography Laboratory, Stazione Zoologica "A. Dohrn; Napoli The Thematic Mapper (TM) sensor's ability to monitor localized phenomena associated with an- thropogenic pollution in coastal waters has been investigated with reference to experimental data collected on a test site in the Gulf of Naples. In situ measurements yielded the biooptical algorithms for chlorophyll and sediment retrieval as well as an optical model for the computation of the subsurface reflectance as a function of water composition, specific to the site. The algorithms" performance was assessed through a sensitivity analysis, taking into account the correlation among chlorophyll, sediment, and yellow substance contents, as well as the stratification characteristics of the water body. Sensitivity analysis techniques were similarly used to evaluate the performance in the coastal environment of three atmospheric correction mod- Address correspondence to S. Tassan, Inst. for Remote Sensing Applications, Commission of the European Communities, Joint Re- search Centre-Ispra Establishment, 21020 Ispra, Italy. Received 1 April 1992; revised 18 October 1992. 0034-4257 / 93 / $6.00 @Elsevier Science Publishing Co. lnc., 1993 655 Avenue of the Americas, New York, NY 10010 els, which assume uniform aerosol load and compo- sition, uniform aerosol composition, and varying aerosol load and composition, respectively. A com- parison with sea-truth data collected for the Land- sat overpass of 22 June 1988 showed a satisfactory correspondence between measured concentrations and concentrations retrieved from the TM data using the above atmospheric correction procedures and "local" biooptical algorithms. Consistent with the indications of the sensitivity analysis, the best agreement was obtained by the atmospheric model assuming varying aerosol load and composition. INTRODUCTION After the demise of the Coastal Zone Color Scan- ner (CZCS) (Hovis, 1981) in 1986, no other color sensor specifically designed for marine applica- tion has come into operation. The launch of the Sea-Viewing Wide-Field-of-View Sensor (Sea- WiFS) has been postponed several times and is 177