LAUSR

Marine litter patches were detected from Sentinel-2 offshore Hawaii's Big Island (Hawaii) within 10 miles from the coast in the prevalent windward direction (NE), for a total sea surface of 3.0 km2. The patches have a filament-like shape with different orientation, lengths of several kilometers and width from tens to hundreds of meters. A comparison with the typical spectra of "sargassum" and "seaweed" patches emphasized differences in the red edge portion of the spectrum for large part of the filaments. Frequency of plastic pollution on Hawaiian beaches and spectral characteristics of the filaments suggest these patches largely consist of plastic debris. A detection method of plastic litter for Sentinel-2 data resampled at 20 m resolution based on the analysis of the red edge bands is proposed.