The interaction between climate change and the Middle Atmosphere often depends upon the nature of the tropospheric response. Among the most uncertain aspects of tropospheric climate change is the question of tropical sensitivity. Here we investigate how different magnitudes of tropical response affect the circulation of the Middle Atmosphere in various climate change situations, including those associated with atmospheric trace gases and/or solar forcing, for paleoclimates, the preindustrial atmosphere, and potential future climates. We utilize a new version of the GISS Global Climate Middle Atmospheric Model incorporating the linearized ozone parameterization (LINOZ). We also indicate how ozone concentrations and transport are affected.