Estimation of Sargassum coverage and its submerged depth within a pixel: a case study for the Yellow sea with GOCI data

Abstract

In this study, we first make use of normalized difference vegetation index (NDVI) to detect all floating vegetation algae. Since S.horneri has high reflectance in near-infrared (NIR) band, the index shows a positive value. With NDVI only, however, S.horneri detection is challenging in turbid waters because NDVI is elevated by the high NIR signals due to mineral particles in turbid waters. So, in the next step, we employed an anomaly detection technique to increase the detection rate of S.horneri both in clear and turbid waters. Finally, we tried to estimate its coverage and submerged depth within a pixel.owever, S.horneri detection is challenging in turbid waters because NDVI is elevated by the high NIR signals due to mineral particles in turbid waters. So, in the next step, we employed an anomaly detection technique to increase the detection rate of S.horneri both in clear and turbid waters. Finally, we tried to estimate its coverage and submerged depth within a pixel.