Research on drawing the distribution envelope of green tide in the Yellow Sea based on satellite remote sensing

Abstract

Since 2007, the continuous large-scale outbreaks of green tides in the Yellow Sea have caused severe impacts on the marine ecological environment and marine economy. Satellite remote sensing monitoring information provides crucial support for emergency decision-making in green tide disasters. The existing monitoring envelope for green tide distribution is drawn using buffer analysis, but the excessive number of vertices poses a significant computational burden for drift prediction. Therefore, this paper developed a method for green tide distribution envelope mapping based on remote sensing images. Firstly, the green tide coverage information was extracted using the NDVI threshold method. Then, the green tide distribution envelope was mapped based on coverage using buffer analysis. Finally, the envelope simplification algorithm based on edge length and vertex angle characteristics (SM-SAC) proposed in this paper was applied to simplify the distribution envelope. This model (SM-SAC) can effectively simplify the vertices, thereby improving the efficiency of green tide distribution drift prediction and providing technical support for developing emergency decision-making plans for green tide disasters.