The aim of the present paper is to investigate further the previously observed dichotomy in the Adriatic waters influenced by the Po river. To that end, an existing algorithm for pigment concentration retrieval has been improved and applied to the reprocessing of selected summer 1981 and winter 1981/1982 images of the Adriatic Sea. The sensitivity loss correction procedure has been included in the retrieval algorithm and rendered coherent with the atmospheric correction model. The model was also updated to allow for multiple Rayleigh scattering, and site-specific calibrated for case 2 waters of the Northern Adriatic. Our analysis of the images reinforces the previous finding (Clement et al., 1987) that two types of CZCS-derived patterns can be observed on the Adriatic shelf: one, elongated, trapped along the Italian coastline; and another wide, irregularly spread into the basin interior. However, according to our results, the two patterns are not seasonally restricted, i. e. both may occur in summer and in winter. In summer, when the Northern Adriatic is stratified, the Po-influenced waters spread at the surface into the basin interior. A lower Po discharge may restrain the river-affected waters to a narrow coastal band. In winter, when the Northern Adriatic is vertically well mixed, the river-affected waters remain confined to the Italian coastal strip all the way down the shelf edge and into the Southern Adriatic. However, strong episodes of spatially heterogeneous bura wind can provoke intrusions into the basin interior.