This three-year study will investigate the inter-relationship between Polar Mesospheric Summer Echoes (PMSE) occurrence, mesospheric temperatures, mesospheric water vapor, and middle-atmosphere dynamics. Further, the PI will differentiate PMSE occurrence in the northern and southern hemispheres. The primary database for PMSE will derive from Poker Flat MST Radar data (northern hemisphere) and data from the Machu Picchu VHF radar located in Antarctica (southern hemisphere). These radars provide a reasonable latitude 'match.' In addition, he will use recent satellite water vapor measurements (HALOE) and middle-atmospheric wind and dynamics data from other high-southern-latitude (MF) radar sites. For the mesospheric temperatures, he will use all published data, new results from the Machu Picchu radar/rocket campaign (PORTA), and a meteor radar system at Machu Picchu to provide additional mesospheric wind and possibly temperature data.
