THE OBJECTIVE OF OUR PROPOSAL IS TO UNDERSTAND THE DYNAMICS OF THE EARTH S MAGNETOPAUSE IN THE PRESENCE OF FLOW SHEARS AND THE EFFECTS OF THESE DYNAMICS ON SOLAR WIND-MAGNETOSPHERE COUPLING AND THE GLOBAL FIELD-ALIGNED CURRENT SYSTEM. ALTHOUGH UBIQUITOUS IN THE GEOSPACE ENVIRONMENT THE VELOCITY SHEARS THAT TRIGGER THE ONSET OF THE KELVIN-HELMHOLTZ INSTABILITY (KHI) AND GENERATE FLOW VORTICITY ARE PARTICULARLY PROMINENT ON THE MAGNETOPAUSE AND ALONG THE INNER EDGE OF THE LOW-LATITUDE BOUNDARY LAYER. SIMULATIONS AND RECENT MULTI-SPACECRAFT OBSERVATIONS SUGGEST THAT THE KHI AND MAGNETIC RECONNECTION CAN OPERATE SIMULTANEOUSLY ON MAGNETOPAUSE AND ALSO THAT FLOW VORTICES CAN GENERATE FIELD-ALIGNED CURRENTS IN THE REGION-1 CURRENT SYSTEM SENSE. THESE STUDIES INDICATE THAT THE ROLES AND EFFECTS OF FLOW SHEARS AROUND THE MAGNETOPAUSE RANGE FROM THE MICROSCOPIC INTERACTIONS WITH RECONNECTION AND CONSEQUENT MODIFICATION OF RECONNECTION PROCESSES TO THE MACROSCOPIC ASPECTS SUCH AS MASS MOMENTUM ENERGY TRANSFER ACROSS THE MAGNETOPAUSE AND THE VORTEX-GENERATED FIELD-ALIGNED CURRENTS THAT CONTRIBUTE TO THE GLOBAL CURRENT SYSTEM. YET OUR KNOWLEDGE OF THE ACTUAL INFLUENCE AND IMPORTANCE OF FLOW VELOCITY SHEAR IN SUCH MICRO-TO-MACROPHYSICAL PROCESSES REMAINS PRIMITIVE. VIA OUR PROJECT WE AIM TO ANSWER INFLUENCES OF FLOW SHEAR AND KINETIC-SCALE VORTICES ON RECONNECTION PROCESSES AND HOW KHI AND RECONNECTION INTERACT ON THE MICROAND MESO-SCALES (Q1) ION/ELECTRON VORTEX DYNAMICS IN TERMS OF THE ORIENTATION/MAGNITUDE OF FLOW VORTICIES (Q2) AND THEIR EFFECT ON THE REGION-1 CURRENT SYSTEM (Q3). THESE TOPICS ARE WELL INTEGRATED TO MAXIMIZE THE SCIENTIFIC RETURN FROM MMS ABILITY TO CALCULATE THE ION AND ELECTRON FLOW VORTICITIES USING ITS TETRAHEDRON FORMATION WITH VARYING INTER-SPACECRAFT SEPARATION DOWN TO THE ELECTRON SCALE. OUR AIM IN ANSWERING Q1-3 IS TO BRING THE MICRO-TO-MACROSCOPIC PIECES OF FLOW SHEAR PROCESSES TOGETHER TO CONSTRUCT A COMPREHENSIVE PICTURE OF THE ROLES AND IMPACTS OF FLOW VORTICES ON THE SOLAR WIND-MAGNETOSPHERE-IONOSPHERE COUPLING. WE WILL ADDRESS THESE QUESTIONS USING A COMBINATION OF METHODOLOGIES THAT INCORPORATE THE AMPLE MMS (FPI FGM EDP EPD HPCA ETC.) OBSERVATIONS OF RECONNECTION WITH/WITHOUT FLOW SHEAR KH VORTICES AND CONJUGATE GROUND MAGNETOGRAMS AND NUMERICAL SIMULATIONS. TO DETERMINE SOLAR WIND AND BOUNDARY CONDITIONS AND PLACE THE MMS OBSERVATIONS IN CONTEXT WE USE SIMULTANEOUS OBSERVATIONS FROM WIND ACE ARTEMIS CLUSTER AND GEOTAIL. WE WILL MAKE FULL USE OF HIGH PERFORMANCE SIMULATION TOOLS 3-D PIC SIMULATIONS. OUR PLAN IS VIA COMPARATIVE STUDIES TO INTEGRATE OUR PHYSICAL UNDERSTANDING GAINED FROM THE SIMULATIONS WITH IN-SITU MMS OBSERVATIONS. UNDERSTANDING THE IMPORTANCE AND EFFECTS OF ION AND ELECTRON FLOW VORTICES GENERATED ALONG THE MAGNETOPAUSE WILL IMPROVE OUR UNDERSTANDING OF THE DYNAMICS AND COUPLING OF EARTH S MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS (DSG #2). IN PARTICULAR OUR STUDY WILL ADDRESS TWO OF THE MOST CRUCIAL PHYSICAL PROCESSES I.E. KHI AND MAGNETIC RECONNECTION THAT ARE FUNDAMENTAL PROCESSES THAT OCCUR BOTH WITHIN THE HELIOSPHERE AND THROUGHOUT THE UNIVERSE (DSG #4). ALL THESE ASPECTS MANIFEST THE RELEVANCE OF OUR PROJECT TO THE FOUR GOALS IN THE HELIOPHYSICS DECADAL SURVEY. THIS PROJECT IS ALSO KEY TO MMS MISSION. THE PROPOSED INVESTIGATION IS DIRECTLY RELEVANT TO THE GOALS OF MMS MISSION: INVESTIGATION OF THE VELOCITY SHEAR EFFECTS ON THE SMALL-SCALE THREE-DIMENSIONAL STRUCTURE AND DYNAMICS OF THE THIN CURRENT LAYERS AND FAST-MOVING ELECTRON DIFFUSION REGION.