Measurements of vertical distributions of velocities and water qualities in Sendai sound in summer using a mobile oceanographical observation platform

Abstract

A mobile oceanographical observation platform, which can measure vertical distributions of water qualities of coastal water and velocities, has been developed in this study. This system was deployed 12 km off Abukuma river mouth in Sendai sound in summer of 2010. The observation results have shown the characteristic three layer structures; the surface layer with low salinity and high water temperature, the middle layer with the salinity maximum, high DO concentration and large mean diameter of SPM and the bottom layer with stable lower temperature and relative high Chlorophyll a. The comparisons of these vertical distributions with the results of water quality survey around Sendai sound and Jyoban coast have suggested that the three layer structure was generated by the intrusion of offshore saline water into the middle layer of Sendai sound.