WE PROPOSE SATELLITE OBSERVATIONAL ANALYSIS AND MODELING STUDIES TO INFORM THE ROLES OF GRAVITY WAVE DYNAMICS ON CHEMICAL TRANSPORT WHICH HAVE IMPACTS ON STRATOSPHERIC CHEMICAL LIFETIMES STRATOSPHERE-TROPOSPHERE EXCHANGE VARIABILITY IN RADIATIVELY ACTIVE GASES AND ASSOCIATED EFFECTS ON CLIMATE. WHILE THE TRADITIONAL VIEW OF STRATOSPHERIC TRANSPORT PRIMARILY HIGHLIGHTS THE ROLE OF GRAVITY WAVES IN DRIVING THE MESOSPHERIC CIRCULATION RECENT RESEARCH HAS HIGHLIGHTED THE IMPORTANT ROLE OF GRAVITY WAVE DRAG DIRECTLY IN THE STRATOSPHERE AND ADDITIONAL RESEARCH SUGGESTS IMPORTANT ROLES IN FINE-SCALE STRATOSPHERE-TROPOSPHERE EXCHANGE PROCESSES. THE PROPOSED PROJECT WILL UTILIZE A VARIETY OF NASA SATELLITE MEASUREMENTS INCLUDING RECORDS LONGER THAN A DECADE TO ADDRESS PROCESSES WITHIN LOCAL EVENTS AS WELL AS LONG-TERM GLOBAL VARIABILITY. OUR WORK VERY DIRECTLY ADDRESSES ONE OF THE OUTSTANDING QUESTIONS FOR THE COMING DECADE REPORTED FOLLOWING THE 2014 WORKSHOP ON ATMOSPHERIC COMPOSITION CHEMISTRY DYNAMICS AND RADIATION AT NASA AMES RESEARCH CENTER NAMELY WHAT ROLE DO GRAVITY WAVES PLAY IN DRIVING THE LARGE-SCALE CIRCULATION? SPECIFIC TO THE AURA SCIENCE TEAM/ATMOSPHERIC COMPOSITION MODELING AND ANALYSIS PROGRAM (AST/ACMAP) ANNOUNCEMENT THE WORK FOCUSES ON MEASUREMENTS FROM THE HIGH RESOLUTION DYNAMICS LIMB SOUNDER (HIRDLS) AND MICROWAVE LIMB SOUNDER (MLS) INSTRUMENTS ON AURA TOGETHER WITH OTHER SATELLITE-BASED PRODUCTS AND PREVIOUSLY DEVELOPED IDEALIZED MODEL TOOLS TO CONSTRAIN REGIONAL GRAVITY WAVE DRAG EVENTS STUDY THEIR DYNAMICAL INTERACTIONS WITH ROSSBY WAVES AND ASSESS EFFECTS IN CHEMICAL TRACER MEASUREMENTS. GRAVITY WAVE DRAG IS ONE COMPONENT OF THE WAVE-DRIVEN FORCE RESPONSIBLE FOR THE GLOBAL STRATOSPHERIC TRANSPORT CIRCULATION THE BREWER-DOBSON CIRCULATION NAMED FOR THE PIONEERING WORK OF A.W. BREWER AND G.M.B. DOBSON WHO INFERRED THIS GLOBAL EQUATOR-TOPOLE CIRCULATION FROM MEASUREMENTS OF OZONE AND WATER VAPOR. THE BREWER-DOBSON CIRCULATION HAS A RANGE OF IMPACTS ON ATMOSPHERIC CHEMISTRY AND CLIMATE. TO FIRST ORDER IT EXPLAINS THE DISTRIBUTION OF THE AGE OF STRATOSPHERIC AIR WHICH HAS IMPORTANT EFFECTS ON THE LIFETIMES OF OZONE-DEPLETING SUBSTANCES AND SOME GREENHOUSE GASES. IT HAS A DOMINANT INFLUENCE ON THE TEMPERATURE OF THE VERY COLD TROPICAL TROPOPAUSE AND CORRESPONDING INFLUENCES ON TROPICAL CIRRUS CLOUDS AND GLOBAL WATER VAPOR WITH ASSOCIATED RADIATIVE EFFECTS AND ROLE IN SURFACE TEMPERATURE VARIABILITY. IN GENERAL THE BREWER-DOBSON CIRCULATION DESCRIBES THE RECIRCULATION PATHWAYS AND THE PROCESSING TIME OF CHEMICAL TRACERS THROUGH THE STRATOSPHERE AND THEIR EVENTUAL RETURN TO THE TROPOSPHERE THEREBY ALSO COMPRISING A MAJOR COMPONENT OF STRATOSPHERE-TROPOSPHERE EXCHANGE. THE CURRENT PARADIGM REPRESENTED IN THE WAY SMALL-SCALE GRAVITY WAVE DRAG PROCESSES ARE TREATED IN GLOBAL MODELS SUGGESTS THAT ONLY OROGRAPHIC GRAVITY WAVE DRAG AFFECTS THE STRATOSPHERE WHILE WAVES FROM OTHER SOURCES LIKE CONVECTION PRIMARILY ONLY AFFECT THE MESOSPHERE DIRECTLY. RECENT OBSERVATIONAL EVIDENCE TELLS A VERY DIFFERENT STORY: INFREQUENT BUT VERY LARGE AMPLITUDE NON-OROGRAPHIC GRAVITY WAVES CARRY A LARGE FRACTION OF THE CIRCULATION-DRIVING FLUX UPWARD ACROSS THE TROPOPAUSE. HENCE THESE LARGE EVENTS VERY LIKELY FORCE THE LOWER STRATOSPHERE DIRECTLY WITH LOCALIZED INTERMITTENT DRAG FORCES. SUCH REALISTIC GRAVITY WAVE-DRIVEN FORCES IN THE STRATOSPHERE ARE NOT CURRENTLY REPRESENTED IN GLOBAL MODELS. OUR WORK WILL QUANTIFY THESE EVENTS USING AURA AND OTHER SATELLITE MEASUREMENTS EXAMINE THEIR INTERACTION WITH LARGER-SCALE SYNOPTIC AND PLANETARY WAVES AND INVESTIGATE THEIR EFFECTS ON CHEMICAL TRACERS IN THE STRATOSPHERE. RECENT RESEARCH SUGGESTS THAT REALISTICALLY INTERMITTENT GRAVITY WAVE DRAG WILL GIVE RISE TO SIGNIFICANTLY MORE VARIABILITY IN CHEMISTRY-CLIMATE MODELS THAN IS CURRENTLY REPRESENTED WITHIN THE CURRENT PARADIGM.