WE PROPOSE TO USE A NEW APPROACH TO STUDY THE GLOBAL EVOLUTION OF THE THERMOSPHERIC NEUTRAL WINDS AT LOW AND MID LATITUDES DURING GEOMAGNETIC STORMS USING THE RECENTLY DEVELOPED PHYSICS-BASED THERMOSPHERIC WIND ASSIMILATION MODEL (TWAM). IN PARTICULAR OUR PROPOSED STUDY WILL INVESTIGATE THE RELATIVE IMPORTANCE OF NEUTRAL WINDS TO DIRECTLY MODIFY THE IONOSPHERIC PLASMA DISTRIBUTION DURING GEOMAGNETIC STORMS. THERMOSPHERIC NEUTRAL WINDS PLAY A MAJOR ROLE IN THE TRANSPORT OF ENERGY AND MOMENTUM IN THE EARTH S UPPER ATMOSPHERE. THEY ARE ALSO RESPONSIBLE FOR CHANGES IN THE COMPOSITION OF THE THERMOSPHERE AND AFFECT THE DYNAMICS AND MORPHOLOGY OF THE IONOSPHERE. HOWEVER DIRECT OBSERVATIONS OF THE WINDS ARE LIMITED BOTH TEMPORALLY AND SPATIALLY WHICH MAKES GLOBAL STUDIES VERY DIFFICULT. ON THE OTHER HAND IONOSPHERIC MEASUREMENTS WHICH CONTAIN INFORMATION ABOUT THE WINDS ARE RELATIVELY EASIER TO MAKE AND HAVE A VERY GOOD DISTRIBUTION OF INSTRUMENTS WORLDWIDE. FOR THIS STUDY WE WILL USE DATA ASSIMILATION MODELS TO EXTRACT THE WIND INFORMATION FROM THIS DATA. IN ORDER TO PERFORM THIS STUDY WE WILL ASSIMILATE A MULTITUDE OF GROUND AND SPACE-BASED OBSERVATIONS INTO THE GLOBAL ASSIMILATION OF IONOSPHERIC MEASUREMENTS FULL PHYSICS (GAIM-FP) MODEL. NEXT THE GAIM-FP OUTPUT I.E. THE MAGNETIC MERIDIONAL WINDS TOGETHER WITH THE 3-D ELECTRON DENSITY AND ION DIFFUSION VELOCITIES ARE ASSIMILATED INTO TWAM TO OBTAIN THE 3-D THERMOSPHERIC NEUTRAL WINDS. FOR THIS WE WILL MODIFY TWAM TO PROCESS DAY-TO-DAY QUIET TIME AND STORMTIME OBSERVATIONS. WE WILL TEST THE MODIFIED MODEL USING SYNTHETIC DATA AND THEN ASSIMILATE REAL OBSERVATIONS. THE RESULTS OF THE MODEL WILL BE VALIDATED WITH DIRECT OBSERVATIONS OF THE NEUTRAL WINDS AND USED TO INVESTIGATE THE GLOBAL EVOLUTION OF THE NEUTRAL WINDS TO GEOMAGNETIC STORMS. FINALLY MODEL RUNS USING OUR ESTIMATED WINDS WILL BE PERFORMED TO ESTABLISH THE RELATIVE IMPORTANCE OF THE NEUTRAL WINDS IN DIRECTLY MODIFYING THE IONOSPHERIC PLASMA DISTRIBUTION.