| Yellow sea attacked by large-scale green macroalgal blooms in summer every year since 2008, and caused tremendous damages to marine ecology and the economy of coastal cities. As a result, many scholars at home and abroad have done a lot of research on green macroalgal blooms. Their work main focused on remote sensing algorithms and three-dimensional marine monitoring systems, but there is little studies for the mechanism of algal blooms with remote sensing. Algae growth and reproduction related to many environmental elements, such as temperature, salinity,light, etc., where the temperature is an important factor for algal generation. Thus,this research will study about sea surface temperature varies during marcoalgal blooms processes.This study researched about sea surface temperature varies during marcoalgal blooms processes in yellow sea based on MODIS(Moderate-Resolution Imaging Spectroradiometer) satellite remote sensing data. First, we extracted the spectral characteristics of enteromorpha, sargassum and water column from MODIS image and established a Macroalgae Index(MI) which can be used to identify macroalgae.And then we extracted sea surface temperature of enteromorpha, sargassum and water column during the macroalgal blooms processes, and analyzed about sea surface temperature varies. Finally, according to the relationship between sea surface temperature and MI during macroalgal blooms processes in algae regions and non-algae regions changes, we analyzed the sea surface temperature changes during the algae outbreaks. The primary research work of this study is as follows:(1) During the processes of algae blooms, sea surface temperature have no significant changes in the before and after outbreak days, while change significantly in the outbreak days.(2) Sea surface temperature of the algae outbreak days is higher than the temperature of the outbreak before and after. Algae regions have different temperature amplitudes, this maybe mainly affected by distribution of algae biomass and density.(3) Sea surface temperature of the algae outbreak days is 3 ℃ higher than the temperature of the outbreak before and after, and sea surface temperature after the outbreak higher than the temperature before the outbreak. Sea surface temperature of algae region is about 1 ℃ higher than temperature of around water columns during algae outbreak days. |
