This note describes the applications of visible- and infrared-remote sensing technique to water quality measurements in inner bays or ports.
　The remote sensing by LANDSAT satellite and aircraft with MSS(multi-spectral scanner), together with sea truth observation, were carried out simultaneously at the mouth of Tokyo Bay.
　The authors applied the statistical analyses to the data obtained from remote sensings and sea truth observation. It has been found that turbidity and temperature in upper layer are highly correlated with remote sensing data. From these results, the estimated features of temperature and turbidity distributions were obtained.
　An attempt was made to estimate the concentration of chlorophyll-a, which led to a conclusion that it is very difficult to measure chlorophyll-a from the remote sensing data. It was found, hwever, that the characteristic of spectral radiance obtained from visible-remote sensing image has a high correlation with the ocean color.