IMPROVING OUR UNDERSTANDING OF THE EVOLUTION OF THE ANTARCTIC ICE SHEET (AIS) SINCE THE LAST GLACIAL MAXIMUM (LGM) IS A KEY TARGET OF STUDIES IN ICE AGE AND MODERN CLIMATE. RECENT RESEARCH HAS SUGGESTED THAT THE EXCESS ICE VOLUME AT LGM (I.E. RELATIVE TO THE PRESENT DAY) WAS A FACTOR OF 2-3 SMALLER THAN PREVIOUS AND WIDELY CITED GLOBAL RECONSTRUCTIONS OF LGM ICE COVER. IF THESE ESTIMATES ARE CORRECT THEN: (1) ~20% OF THE GLOBAL ICE BUDGET AT LGM IS UNACCOUNTED FOR INTRODUCING A SIGNIFICANT MISSING MASS PROBLEM; (2) THE AIS COULD NOT HAVE BEEN A SIGNIFICANT CONTRIBUTOR TO A HIGHLY DEBATED CLIMATE EVENT KNOWN AS MELTWATER PULSE 1A CHARACTERIZED BY A ~10-15 M JUMP IN GLOBALLY AVERAGED SEA LEVEL IS LESS THAN 300 YEARS; AND (3) THE IMPACT OF MELTING FROM THE AIS ON NORTHERN HEMISPHERE CLIMATE (VIA A PERTURBATION IN OCEAN CIRCULATION) WOULD HAVE BEEN MINOR. THE RECENT LOWERING OF ESTIMATES OF AIS ICE VOLUME AT LGM HAS ALSO SIGNIFICANTLY IMPACTED OUR UNDERSTANDING OF AIS CONTRIBUTION TO RECENT SEA-LEVEL CHANGE IN THE FACE OF CLIMATE CHANGE BY REDUCING THE PREDICTED SIGNAL OF ONGOING GLACIAL ISOSTATIC ADJUSTMENT (GIA) IN SPACE GEODETIC (GPS GRACE GRAVITY) MEASUREMENTS. ANALYSIS OF THE GIA-CORRECTED RESIDUALS IN THESE MEASUREMENTS HAS LOWERED ESTIMATES OF ONGOING ICE MASS LOSS FROM THE AIS. A MAJOR SHORTCOMING OF THE RECENT ESTIMATES OF AIS ICE VOLUMES DURING LGM HAS BEEN THAT THEY HAVE BEEN LARGELY BASED ON GIA SIMULATIONS IN WHICH EARTH STRUCTURE VARIES WITH DEPTH ALONE. HOWEVER THE GEOLOGY OF THE ANTARCTIC AN AMALGAM OF THE CRATONIC EAST ANTARCTIC THE WEST ANTARCTIC RIFT SYSTEM AND THE UPLIFTED TRANSANTARCTIC MOUNTAINS AS WELL AS HIGH-RESOLUTION SEISMIC TOMOGRAPHIC IMAGING INDICATES PROFOUND LATERAL VARIATIONS IN LITHOSPHERIC THICKNESS AND UPPER MANTLE VISCOSITY. WE PROPOSE TO USE A STATE-OF-THE-ART GIA SIMULATOR THAT INCORPORATES A RANGE OF RHEOLOGICAL MODELS AND PERMITS EXTREME VARIATIONS IN VISCOELASTIC EARTH STRUCTURE TO CONSTRUCT A NEW MODEL OF AIS EVOLUTION SINCE THE LGM. OUR MODEL WILL BE CONSTRAINED BY ALL RELEVANT GEOLOGICAL SURFACE OBSERVATIONS (E.G. LOCAL RELATIVE SEA LEVEL HISTORIES) AND THE MAPPING FROM SEISMIC VELOCITY HETEROGENEITY TO MANTLE STRUCTURE WILL BE CONSISTENT WITH RESULTS FROM MINERAL PHYSICS EXPERIMENTS ON MANTLE MATERIALS. WE WILL USE THE NEW AIS MODEL TO REVISIT THE IMPORTANT PALEOCLIMATE ISSUES LISTED ABOVE AND THROUGH A NEW ANALYSIS OF GIA-CORRECTED SPACE-GEODETIC OBSERVATIONS REASSESS THE CONTRIBUTION OF THE AIS TO RECENT GLOBAL SEA-LEVEL RISE.