Drift path of green tide and the impact of typhoon “Chan-hom” in the Chinese Yellow Sea based on GOCI images in 2015

Abstract

Since 2007, green tide disasters have occurred in Chinese Yellow Sea for 11 consecutive years. The continuous outbreak of green tides has caused various degrees of economic loss and ecological damage to coastal areas. In this study, we use GF1-WFV (GaoFen No.1-Wide Field of View) high resolution images and GOCI (Geostationary Ocean Color Imager) images comprehensively. NDVI (Normalized vegetation index), linear decomposition model of mixed pixels (LDMMP) and artificially assisted interpretation methods were used to monitor the green tide eruptions in the Yellow Sea in 2015. The impact of the typhoon “Chan-hom” on the green tide growth process and drift path were analyzed for the first time. The results showed that: The accuracy of extracting green tide area by LDMMP method is higher than that of NDVI. Based on GOCI images, the distribution of green tides in the study area in 2015 was obtained using the LDMMP method; From May to August, the green tide in the Yellow Sea has undergone the process of “emergence-development-explosion-decline-disappearance”; Typhoon “Chan-hom” changed the path of the green tide continuing to the north to a certain extent and drifted to the southeast, causing the center of the green tide to move to Lianyungang Eastern waters.