POSTER SESSION 3
15:30–17:30, Wednesday, September 16
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1220 | POSTER 31
CAPTURING SPATIAL AND TEMPORAL GRADIENTS OF OPTICAL WATER TYPES IN A RIVER SYSTEM
Monitoring optical variability in large rivers is crucial for advancing aquatic optics and for enhancing our understanding of hydrological processes, water quality dynamics, and land-sea interactions. We present a one-year analysis of continuous hyperspectral radiometric measurements collected by a WISPstation spectroradiometer installed on the Po River, approximately 95 km upstream of the Northern Adriatic Sea. In situ data were processed through an automated workflow including quality control and sky-glint correction to retrieve remote sensing reflectance (Rrs). Daily mean Rrs spectra were used to identify six Optical Water Types (OWTs), representing distinct river optical conditions linked to different hydrological and discharge regimes and associated variations in suspended and dissolved substances. The temporal occurrence of OWTs exhibited strong variability from daily to seasonal scales, demonstrating the capability of continuous radiometric observations for capturing optical dynamics. The OWT classification was applied to Sentinel-2 imagery atmospherically corrected with ACOLITE RadCOR using a Spectral Angle Mapper approach. Resulting maps describe the spatial distribution of riverine optical conditions along the land-sea continuum, enabling synoptic observations of gradients and frontal structures. Under flood events, regions of freshwater influence driven by plume transport and mixing are clearly delineated in the coastal area and distinguished from marine waters. Pixels not associated with any riverine OWT predominantly reflected estuarine or marine optical conditions, suggesting a potential proxy for detecting tidal influence and saltwater intrusion. This study demonstrates how autonomous radiometry combined with satellite observations supports scalable monitoring of large rivers and assessment of climate and discharge-driven changes in transitional environments.
Gian Marco Scarpa, CNR-ISMAR, [email protected], https://orcid.org/0000-0002-5061-5607
Federica Braga (Presenting), CNR, [email protected], https://orcid.org/0000-0002-4131-9080
Debora Bellafiore, CNR-ISMAR, [email protected], https://orcid.org/0000-0003-2442-3916
Vittorio Brando, CNR-ISMAR, [email protected], https://orcid.org/0000-0002-2193-5695
Francesca De Pascalis, CNR-ISMAR, [email protected], https://orcid.org/0000-0002-1694-882X
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
