Acronym Definition BRDF Bidirectional Reflectance Distribution Function CSS Calibration Support Segment DCC Deep Convective Cloud GCC GSICS Coordination Centre CGMS Coordination Group for Meteorological Satellites GDWG GSICS Data Management Working Group GPAP GSICS Product Acceptance Procedure GPRC GSICS Production and Research Centre GRWG GSICS Research Working Group GSICS Global Space-based Inter-calibration System PSF Point Spread Function QA4EO Quality Assurance Framework for Earth Observation ROLO Robotic Lunar Observatory RTM Radiative Transfer Model SI International System of Units SNO Simultaneous Nadir Observation SRF Spectral Response Function TOA Top of Atmosphere