BACKGROUND: OVER THE PAST DECADE ADVANCES IN THEORY MODELING AND GROUND-BASED OBSERVATIONS COLLECTIVELY INDICATE THAT GRAVITY WAVES (GW) EXCITED IN THE LOWER ATMOSPHERE CAN HAVE PROFOUND EFFECTS ON THE MEAN STATE AND VARIABILITY OF THE IONOSPHERE-THERMOSPHERE- MESOSPHERE (ITM) SYSTEM (CA. 50-500 KM). DISSIPATING WAVES CAN DEPOSIT NET MOMENTUM DRIVE MEAN CIRCULATIONS AND THERMAL STRUCTURES AND INDUCE COMPOSITION CHANGES THROUGH NET WAVE TRANSPORT AND EDDY DIFFUSION. A SIGNIFICANT HINDRANCE TO ADVANCING KNOWLEDGE IS THE ABSENCE OF A GLOBAL DELINEATION OF GW AND THEIR CONTEMPORANEOUS EFFECTS IN THE ITM. THIS PROPOSAL EMPLOYS DATA FROM THE ONGOING AIM AND TIMED MISSIONS TO ADDRESS THIS KNOWLEDGE GAP. THIS PROPOSAL IS PROMPTED BY A NEW CONTINUOUS IMAGING (CI) OPERATING MODE OF THE CIPS (CLOUD IMAGING AND PARTICLE SIZE) INSTRUMENT ON THE AIM SATELLITE. IN CI MODE CIPS PERFORMS RAYLEIGH ALBEDO ANOMALY (RAA) MEASUREMENTS NEAR THE 50-KM BASE OF THE ITM REGION WHICH CAN REVEAL GW TEMPERATURE PERTURBATIONS AND THE PRESENCE AND INTENSITY OF GW WITH HORIZONTAL SCALES AS SHORT AS 15 KM OVER THE SUNLIT PORTION OF THE GLOBE (EXCEPT AT SUMMER POLAR LATITUDES). THE CIPS/CI MEASUREMENTS WILL REVEAL THE GW SCALES PREDICTED TO HAVE THE GREATEST IMPACTS AT HIGHER ALTITUDES. CURRENTLY AVAILABLE GLOBAL DATA COVER THE PERIOD BETWEEN FEB 2016-FEB 2017. HISTORICAL DATA SINCE 2007 ARE AVAILABLE AT MIDDLE TO HIGH LATITUDES EXCEPT FOR SUMMER MONTHS AND WILL PROVIDE INSIGHTS INTO INTER-ANNUAL VARIABILITY. CONTEMPORANEOUS TIMED/GUVI MEASUREMENTS SINCE 2007 WILL IDENTIFY GLOBAL STRUCTURES OF COMPOSITION EFFECTS ATTRIBUTABLE TO VERTICALLY-PROPAGATING GW. NASA MISSION DATA TO BE EMPLOYED: (1) GLOBAL AIM/CIPS MEASUREMENTS OF GW NEAR 50 KM ALTITUDE FOR AT LEAST THE PERIOD BETWEEN FEB 2016-FEB 2017 AND 2007-2015 AT MIDDLE TO HIGH LATITUDES EXCEPT DURING SUMMER MONTHS; AND (2) GLOBAL TIMED/GUVI MEASUREMENTS OF HEIGHT-INTEGRATED O/N2 DENSITY RATIO OVER THE SAME PERIODS. SCIENCE GOALS: (1) DETERMINE THE GLOBAL (LATITUDE VS. LONGITUDE BOTH HEMISPHERES) DISTRIBUTION OF TEMPERATURE VARIANCES ASSOCIATED GW ENTERING THE ITM AND HOW IT VARIES OVER INTRA-SEASONAL INTRA-ANNUAL AND INTER-ANNUAL TIME SCALES; AND (2) ESTABLISH CONNECTIONS BETWEEN THE SPATIAL-TEMPORAL DISTRIBUTION OF GW ENTERING THE ITM AND (A) GW SOURCES AND (B) LOWER THERMOSPHERE CHEMICAL COMPOSITION. METHODOLOGY: CIPS/CI MEASUREMENTS WILL BE ANALYZED TO DELINEATE THE GLOBAL DISTRIBUTIONS OF GW TEMPERATURE VARIANCES WITH HORIZONTAL SCALES BETWEEN 15-200 KM BETWEEN FEB 2016-FEB 2017 AND AT MIDDLE TO HIGH LATITUDES IN BOTH HEMISPHERES (EXCEPT FOR SUMMER MONTHS) SINCE 2007. CLIMATOLOGICAL DISTRIBUTIONS OF KNOWN TROPOSPHERIC GW SOURCES WILL BE USED TO ASCERTAIN THE LIKELY SOURCES OF THE OBSERVED GW. THE SOLAR TERMINATOR WILL ALSO BE INVESTIGATED AS A GW SOURCE. SIGNIFICANT CORRELATIONS BETWEEN LATITUDE LONGITUDE VS. TIME STRUCTURES OF GW TEMPERATURE VARIANCES AND O/N2 RATIOS WILL BE TAKEN AS EVIDENCE FOR GW-INDUCED COMPOSITION EFFECTS. RELEVANCE TO AIM AND DECADAL SURVEY: AIM WAS ORIGINALLY DESIGNED TO MEASURE POLAR MESOSPHERIC CLOUDS SO THE MODE OF OPERATION WAS NOT IDEAL FOR GW STUDIES. WITH THE NEW CI MODE OF OPERATION THE CURRENT EXTENDED MISSION PROPOSAL INCLUDES CONTINUED PRODUCTION OF GLOBAL GW IMAGES FROM CIPS BUT NO SPECIFIC SCIENCE PROPOSALS ARE MADE TO CONSTRUCT A GLOBAL GW CLIMATOLOGY AND/OR ITS CONNECTION TO LOWER THERMOSPHERE COMPOSITION. THEREFORE THE CURRENT PROPOSAL BOTH ADDRESSES AND EXTENDS THE SCIENCE THAT CAN BE DONE WITH AIM MEASUREMENTS AND MOREOVER RESPONDS TO DECADAL SURVEY SCIENCE GOAL #2 "DETERMINE THE DYNAMICS AND COUPLING OF EARTH S MAGNETOSPHERE IONOSPHERE AND ATMOSPHERE AND THEIR RESPONSE TO SOLAR AND TERRESTRIAL INPUTS" BY ADDRESSING AIMI SCIENCE PRIORITY 2 UNDERSTAND HOW TROPOSPHERIC WEATHER INFLUENCES SPACE WEATHER AND AIMI SCIENCE GOAL 2: HOW DOES LOWER-ATMOSPHERE VARIABILITY AFFECT GEOSPACE?