MESOSCALE EDDIES ARE UBIQUITOUS IN THE WORLD OCEAN. A CONSIDERABLE AMOUNT OF KNOWLEDGE ABOUT MESOSCALE EDDIES HAS BEEN GAINED ESPECIALLY SINCE THE ADVENT OF SATELLITE ALTIMETRY IN THE 1980S. HOWEVER MOST PREVIOUS WORK HAS FOCUSED ON SIGNALS NEAR THE SEASURFACE AND MORE RECENTLY DOWN TO ABOUT 2000 M (THANKS TO ARGO). THE SIGNALS OF MESOSCALE EDDIES IN THE DEEP OCEAN AND THEIR INFLUENCE ON THE DEEP-OCEAN DYNAMICS HAVE NOT YET BEEN INTENSIVELY STUDIED. RECENTLY A FEW REGIONAL STUDIES FOUND THAT MESOSCALE EDDIES CAN SIGNIFICANTLY INFLUENCE A VARIETY OF DEEP OCEAN PROCESSES INCLUDING SUBINERTIAL FLOWS INTERNAL WAVES AND DIAPYCNAL MIXING. CONSIDERING THE UBIQUITOUSNESS OF MESOSCALE EDDIES IN THE GLOBAL OCEAN IT IS EXPECTED THAT DEEP-OCEAN CURRENTS ARE COMMONLY AFFECTED BY MESOSCALE VARIABILITY PARTICULARLY NEAR LARGE TOPOGRAPHY. THESE EDDY-INFLUENCED DEEP OCEAN CURRENTS MAINLY SUBINERTIAL LIKELY CONTRIBUTE TO DRIVING DISSIPATING AND MODULATING INTERNAL WAVES AND CONSEQUENTLY ARE EXPECTED TO AFFECT TURBULENCE AND MIXING AS WELL. THE PRIMARY AIM OF THIS PROPOSED PROJECT IS TO EXPLORE TO WHAT EXTEND MESOSCALE EDDIES WHICH CAN BE IDENTIFIED WITH SATELLITE MEASUREMENTS AFFECT THE DEEP-OCEAN CURRENTS AROUND THE GLOBAL OCEAN AND HOW THE EDDY-RELATED DEEP-OCEAN CURRENTS MODULATE AND/ OR GENERATE DEEP-OCEAN INTERNAL WAVES. TO ACHIEVE THIS GOAL WE PROPOSE TO COMBINE THE ALTIMETER DATA AND AN ARCHIVE OF DEEP-OCEAN MEASUREMENTS TO INVESTIGATE THE CONNECTIONS BETWEEN SURFACE-OBSERVED MESOSCALE EDDIES AND DEEP-OCEAN DYNAMICAL PROCESSES SUCH AS SUBINERTIAL FLOWS AND INTERNAL WAVES OVER THE GLOBAL OCEAN. WE WILL FIRST OBTAIN SUBINERTIAL CURRENTS IN THE LESS-STUDIED DEEP OCEAN (BELOW 2000 M) AND EXAMINE UNDER WHAT CIRCUMSTANCES THESE CURRENTS ARE ASSOCIATED WITH MESOSCALE EDDIES REVEALED IN THE ALTIMETER DATA. THEN WE WILL INVESTIGATE THE RELATIONSHIPS BETWEEN SUBINERTIAL CURRENTS AND NEAR-INERTIAL/TIDAL CURRENTS IN THE DEEP OCEAN IN RELATIONSHIPS ALSO TO OTHER FACTORS (E.G. TOPOGRAPHY LATITUDE AND REGIONAL CIRCULATION). THE PROPOSED STUDIES ARE CLOSELY RELEVANT TO NASA. ONE OF THE TWO PRIMARY DATA SOURCES IS THE ALTIMETER DATA FROM VARIOUS NASA MISSIONS. MOREOVER THE PROPOSED ANALYSES WILL EXTEND THE USE OF SATELLITE MEASUREMENTS TO THE STUDY OF THE DEEP OCEAN WHICH IS STILL POORLY UNDERSTOOD. ALSO SINCE FREQUENCY AND INTENSITY OF MESOSCALE EDDIES DEPEND ON THE STATE OF THE CLIMATE THE EDDY MODULATION OF DEEP-OCEAN CURRENTS INTERNAL WAVES AND MIXING CONNECTS CLIMATE CHANGE AND CLIMATE VARIABILITY TO PHYSICAL AND BIOGEOCHEMICAL PROCESSES IN THE DEEP OCEAN ALLOWING FOR UNEXPLORED CLIMATE FEEDBACK MECHANISMS. THUS THE PROPOSED ANALYSES WILL ALSO CONTRIBUTE TO ONE OF THE MAJOR FOCUS AREAS OF THE NASA'S MISSION IN EARTH SYSTEM SCIENCE --- CLIMATE VARIABILITY AND CHANGE.