Spectral Discrimination of Pumice Rafts in Optical MSI Imagery

Pumice rafts are considered to be a long-range drifting agent that promotes material exchange and the dispersal of marine species. Large ones can also interfere with vessel navigation have negative impact on social economy ecosystems. Synoptic observations from Multispectral Instrument (MSI) on-board Sentinel-2, spatial resolution up 10 m, provide an excellent means monitor track pumice rafts. In this study, use Spectral-Feature-Based Extraction (SFBE) algorithm automatically discriminate extract ocean surface submarine volcano eruptions was proposed. Specifically, Raft Index (PRI) developed based spectral signatures in MSI imagery identify potential features. After pre-processing, PRI image then subjected series per-pixel object-based processes rule out false-positive detections, including shallow water, striped edges, mudflats, cloud edges. The SFBE showed performance extracting successfully applied near Fiji Yasawa islands 2019 Hunga Tonga island 2022, overall extraction accuracy 95.5% proportion pixels mis-extracted as <3%. robustness has been tested proved through applying it data comparing its output results previous studies. timely accurate detection using proposed here is expected important information aid response actions ecological assessments, will lead better understanding fate pumice.