THIS GRANT IS REQUESTED FOR TEXAS A AND M UNIVERSITY TAMU AS A SUBAWARD OF A NASA PROJECT ENTITLED SWIRP COMPACT SUBMMWAVE AND LWIR POLARIMETERS FOR CIRRUS ICE PROPERTIES. PROF. PING YANG FROM THE DEPARTMENT OF ATMOSPHERIC SCIENCES TAMU IS A COINVESTIGATOR OF AFOREMENTIONED NASA PROJECT. THE TAMU TEAM WILL SUPPORT THE SWIRP PROJECT BY CONDUCTING RADIOMETRICPOLARIMETRIC SIMULATIONS. THE TAMU TEAM HAS DEVELOPED UNIQUE INNOVATIVE AND FAST MODELING CAPABILITIES FOR ICE PARTICLE SCATTERING CALCULATIONS INCLUDING THE INVARIANT IMBEDDING TMATRIX MODEL AN IMPROVED GEOMETRIC OPTICS METHOD AND A COMPUTATIONALLY EFFICIENT POLARIZED RADIATIVE TRANSFER MODEL WHICH CAN BE USED FOR EVALUATING THE SENSITIVITY OF SWIRP POLARIMETERS TO VARIOUS CLOUD PARTICLE SIZES AND SHAPES. THE SCATTERING ABSORPTIONPOLARIZATION PROPERTIES OF ICE CRYSTALS COMPUTED FROM THE TAMU ALGORITHMS ARE CONSISTENT ACROSS ALL SPECTRAL FREQUENCIES FROM SOLAR BANDS INFRARED BANDS TO MICROWAVE BANDS. THESE COMPUTATIONAL CAPABILITIES ARE CRITICAL FOR SYNERGISTIC REMOTE SENSING IN THE FUTURE MISSIONS. FOR THE SWIRP PROJECT WE WILL FOCUS ON THE RADIOMETRIC AND POLARIMETRIC PROPERTIES OF ICE CLOUDS AT 220 680 GHZ AND 8.6 11 AND 12 M BANDS. THE SPECIFIC TASKS INCLUDE TASK 1 DETERMINE THE SCATTERING ABSORPTION POLARIZATION PROPERTIES OF INDIVIDUAL ICE CRYSTALS WITH TWO TYPICAL PARTICLE SHAPES HEXAGON AND AGGREGATES AT THE SELECTED BANDS. ALTHOUGH REALISTIC ICE CRYSTAL SHAPES ARE QUITE COMPLICATED THE USE OF THE AFOREMENTIONED TWO PARTICLE SHAPES PRODUCES OPTIMAL OPTICAL PROPERTIES OF ICE CLOUDS WHICH LEAD TO A SPECTRALLY CONSISTENT OPTICAL MODEL IN THE SOLAR INFRARED AND MICROWAVE REGIONS IE CONSISTENT RETRIEVALS BASED ON THESE CLOUD REMOTE SENSING BANDS. TASK 2 DEVELOP A BULK ICE CLOUD MODEL AT THE SELECTED BANDS BY CONSIDERING PARTICLE SIZE DISTRIBUTION. FOR EACH SIZE BIN THE PERCENTAGE OF THE AFOREMENTIONED TWO PARTICLE SHAPES MAY VARY WITH RESPECT TO PARTICLE SIZE BIN. IN PARTICULAR PRISTINE HEXAGONAL ICE CRYSTALS DOMINATE IN SMALL SIZE BINS WHEREAS LARGE PARTICLES ARE MAINLY AGGREGATES. TASK 3 INCORPORATE THE BULK SCATTERING ABSORPTION POLARIZATION PROPERTIES INTO A VECTOR RADIATIVE TRANSFER MODEL TO EXPLORE ICE CLOUD CHARACTERISTICS FROM RADIOMETRIC AND POLARIMETRIC FEATURE PERSPECTIVES. THE EFFICIENT POLARIZED RADIATIVE TRANSFER MODEL DEVELOPED AT TEXAS A&M UNIVERSITY WILL BE USED FOR THIS TASK.