SYNOPSIS SURFACE SNOW AND ICE CLOUDS HAVE IMPORTANT IMPACTS ON THE EARTH S RADIATION BUDGET. THE SINGLE-SCATTERING PROPERTIES NAMELY THE PHASE FUNCTION SINGLE-SCATTERING ALBEDO AND EXTINCTION EFFICIENCY OF ICE CRYSTALS ARE FUNDAMENTAL TO THE RADIATIVE TRANSFER AND REMOTE SENSING OF ICE CLOUDS AND SNOW. ICE CRYSTALS IN CLOUDS AND SNOW PARTICLES ARE EXTREMELY COMPLICATED. THEIR OPTICAL PROPERTIES ARE SIGNIFICANTLY DIFFERENT FROM EQUIVALENT ICE SPHERES. IT IS NECESSARY TO USE APPROPRIATE OPTICAL PROPERTIES OF ICE CRYSTAL AND SNOW PARTICLES IN RADIATIVE TRANSFER SIMULATIONS AND REMOTE SENSING CONCERNING ICE CLOUDS AND SNOW. OUR RESEARCH GROUP AT TEXAS A&M UNIVERSITY HAS DEVELOPED UNIQUE CAPABILITIES FOR SIMULATING THE OPTICAL PROPERTIES OF ICE CRYSTALS AND HAS BEEN LEADING IN THIS SPECIFIC RESEARCH AREA. FOR THIS PROJECT WE PROPOSE BUILDING ON EXISTING ON RESEARCH TO SIMULATE THE OPTICAL PROPERTIES OF ICE/SNOW PARTICLES IN SUPPORT OF THE NASA CERES (CLOUDS AND THE EARTH S RADIANT ENERGY SYSTEM) SCIENCE TEAM. SPECIFICALLY WE PROPOSE THE FOLLOWING THREE MAJOR TASKS: IMPROVE AND VALIDATE A NEW ICE CLOUD BULK RADIATIVE PROPERTY MODEL; FURTHERMORE GENERATE LOOK-UP TABLES (LUTS) IN SUPPORT OF THE CLOUD PROPERTY RETRIEVALS BY THE CERES SCIENCE TEAM USING THE MODERATE RESOLUTION IMAGING SPECTRORADIOMETER (MODIS) AND THE VISIBLE AND INFRARED IMAGING RADIOMETER SUITE (VIIRS) OBSERVATIONS. DEVELOP A NOVEL SNOW ALBEDO MODEL IN SUPPORT OF THE RADIATIVE TRANSFER MODEL USED BY THE CERES TEAM FOR FLUX CALCULATIONS. DOCUMENT AND DELIVER THE OPTICAL PROPERTY AND LUT DATA; FURTHERMORE PUBLISH THE RESEARCH FINDINGS IN PEER-REVIEWED SCIENTIFIC JOURNALS.