THE TURBOPAUSE REGION REMAINS ONE OF THE MOST POORLY EXPLORED YET CRUCIAL REGIONS OF THE UPPER ATMOSPHERE. IN THE VICINITY OF THIS ALTITUDE THE ATMOSPHERE REACHES ITS LOWEST TEMPERATURE AND THE COMPOSITIONAL STRUCTURE CHANGES FROM BEING GOVERNED BY TURBULENT MIXING PROCESSES TO DIFFUSIVE PROCESSES. DYNAMICAL ENERGY IN THE FORM OF TIDES AS WELL AS GRAVITY AND PLANETARY WAVES PROPAGATE FROM THE LOWER ATMOSPHERE TO THE IONOSPHERE