Development of an automated hyperspectral system to monitor hyperspectral reflectance and sun-induced chlorophyll fluorescence with directional and hemispheric view geometries simultaneously

Simultaneous observations of directional and hemispherical reflectance and emission are valuable to understand canopy structural and physiological dynamics. However, employing both observation geometries concurrently to measure either reflectance or sun-induced chlorophyll fluorescence (SIF) remains challenging and therefore has rarely been explored with continuous observations. Here, we designed and implemented the enhanced RotaPrism system, an automated instrument that integrates a hyperspectral sensor for reflectance measurements and a hyperspectral sensor with much higher spectral resolution for SIF retrieval, enabling monitoring of both hemispherical and directional viewing geometries. We installed this system at a rice paddy and a mixed forest site, collecting spectral data continuously throughout the growing season. We assessed instrumental uncertainty through quality control prot…