*Hiroki Mizuochi1, Satoshi Tsuchida1, Satoru Yamamoto1, Minoru Urai1, Moe Matsuoka1, Ayame Ikeda1, Koki Iwao1
(1.National Institute of Advanced Industrial Science and Technology)
Keywords:Cross calibration, Hyperspectral Imager Suite (HISUI), Coastal environmental monitoring
Hyperspectral remote sensing provides detailed spectral features of the Earth’s surface and have revealed a wide range of applications in environmental monitoring. One of the recent spaceborne hyperspectral imagers, the Hyperspectral Imager Suite (HISUI), was installed on the International Space Station (ISS) in 2019 and had acquired several hundred thousand scenes up to now. In this study, we provide recent results of cross- and inter-band calibration activities to ensure inter-band consistency and time-series stability of HISUI radiance data. Using well-calibrated reference sensors (the Moderate Resolution Imaging Spectroradiometer; MODIS) with correction of difference in spectral response function, spatial resolution, sensor geometry from HISUI, we revealed time-series change in sensor sensitivity of HISUI from 2021 to 2023. In particular, substantial discrepancy between the visible to near-infrared (VNIR) and short-wave infrared (SWIR) domains was reported, contributing to update of HISUI calibration parameters to create spectrally consistent product. We further discuss potential applications of spaceborne hyperspectral imagers to shallow-water environmental monitoring, including benthic cover classification, water depth mapping, and water quality (e.g., chl-a) estimation.