Plastic Litter Project 2026
Project Description
The main goal of PLP2026 is to acquire a series of Sentinel-2 images that will enable the extraction of pure-pixel spectral signatures of reference materials representative of floating marine plastic litter. A pure pixel refers to a 10 × 10 m Sentinel-2 pixel that is entirely covered by the artificial target, with no contribution from the surrounding seawater. The resulting pure-pixel spectral signatures will enable the application of spectral classification methods without the need for spectral unmixing procedures.
To successfully acquire pure-pixel spectral signatures, our team constructed floating targets consisting of white HDPE mesh with white plastic bottles positioned at their center to provide buoyancy. The targets are deployed in the Gulf of Gera, on the island of Lesvos, for a period of 2–4 months using a dedicated mooring system similar to those employed in commercial aquaculture facilities. The mooring system and buoy specifications comply with maritime regulations and ensure the safe, stable, and long-term deployment of the targets.
The selected white HDPE mesh serves as the reference material because of its composition and color, as white HDPE items are among the most frequently encountered types of marine plastic litter. In addition, the material is lightweight, durable, and practical for constructing large-area targets required for satellite observations.
The target design includes surface areas of 18 m², 45 m², and 90 m², corresponding to specific fractional coverage percentages of PRISMA and Sentinel-2 pixels. These dimensions were selected to evaluate the detection limits of both sensors under realistic field conditions, spanning a range of target sizes that extends beyond the detection thresholds reported in previous studies.
Expected Outcomes
The continued development of a remote sensing database and spectral library containing representative spectral signatures of floating marine litter. This dataset will provide a valuable resource for the development, calibration, and validation of remote sensing algorithms for the detection and quantification of floating marine litter.
Further identification and quantification of the factors influencing the remote sensing detectability of floating marine litter, together with an assessment of the limitations of current satellite and unmanned aerial system (UAS) platforms and sensors. The findings will contribute to defining the technical specifications and observational requirements—such as radiometric, spatial, and spectral resolution—of future satellite missions dedicated to the detection and long-term monitoring of floating marine litter.