BATHYMETRY MAPPING USING HYPERSPECTRAL DATA: A CASE STUDY OF YAMADA BAY, NORTHEAST JAPAN
- 1Asia Air Survey Co., Ltd., 1-2-2 Manpukuji, Asao, Kawasaki, Kanagawa 215-0004 Japan
- 2Japan Space Systems, 3-5-8 Shibakoen, Minato-ku, Tokyo 105-0011 Japan
Keywords: CASI-1500h, inversion method, semi-analytical model, simulation, seagrass meadow, shallow water
Abstract. This study aims to examine if the inversion method using hyperspectral data is applicable in Japan. Nowadays, overseas researchers are mainly applied an inversion method for accurately estimating water depth. It is able to gain not only water depth, but also benthic spectral reflection and inherent optical properties (IOPs) at the same time, based on physics-based radiative transfer theory for hyperspectral data. It is highly significant to understand the possibility to develop the application in future for coastal zone of main island, which is a common water quality in Japan, but there is not any case study applied this method in Japan. The study site of Yamada bay in Iwate Prefecture is located in northeast of Japan. An existed analytical model was optimized for mapping water depth in Yamada bay using airborne hyperspectral image and ground survey data which were simultaneously acquired in December, 2015. The retrieved remote-sensing reflectance (Rrs) is basically qualitatively appropriate result. However, when compared with all ground survey points, the retrieved water depth showed low correlation, even though ground points which are selected sand bottom indicates high relationship. Overall, we could understand the inversion method is applicable in Japan. However, it needs to challenge to improve solving error-caused problems.