Phenological eyes network (PEN) is designed as a validation campaign of satellite remote sensing data for terrestrial ecosystem observation. This project has started in several carbon-flux observatories of AsiaFlux projects. Main part of PEN consists of three core instruments : Automatic-capturing Digital Fisheye Camera (ADFC), HemiSpherical Spectro-Radiometer (HSSR) and SunPhotometer (SP). ADFC serves images mainly for a phenological study, sky condition and leaf area index (LAI). HSSR provides vegetation spectral parameters and a photosynthetically active radiation. SP provides atmospheric parameters for an atmospheric correction of satellite images. In combination with these PEN observations and flux or ecosystem research, validation study of ecosystem remote sensing will be enhanced in various aspects, namely, radiative quality check as well as ecological standpoints. PEN is an open project and welcomes involvements from various groups.
