Red tide detection by means of peak shift of remote sensing reflectance and possibility of red tide detection with polarized radiance measurements

摘要

A method for detection of red tide by means of remote sensing reflectance peak shift is proposed together with suspended solid influence eliminations. Although remote sensing reflectance peak is situated at around 550nm for sea water without suffered from red tide, the peak is shifted to the longer wavelength when sea water is suffered from red tide. Based on this fact, it is capable to detect red tide using high wavelength resolution of spectral-radiometers. The proposed system uses web camera with band-pass filter on the optics surface. Acquired imagery data can be transmitted through wireless LAN to Internet terminal and can be archived in server through Internet. Validity of the proposed method is confirmed with the system deployed in Ariake Sea which is situated in northern Kyushu, Japan. Also a method for red tide detection with satellite imagery data is attempted with suspended solid influence eliminations. Furthermore, a possibility of red tide detection with polarized radiance measurements is discussed through polarization camera derived sue surface imagery data, in particular, for non-spherical shape of red tide.