We compare two simulations of the middle atmosphere using the NCAR Whole Atmosphere Community Climate Model, which includes a comprehensive middle atmosphere chemistry model. Ozone is fully interactive in the first simulation. A zonal mean and monthly mean ozone climatology is constructed from the interactive simulation. That ozone climatology is used to determine the radiative heating rates in the second simulation. Comparison of the two simulations shows that using the zonal-mean ozone climatology significantly affects the climate of the middle atmosphere. Differences between the two simulations are statistically significant throughout the tropics in the upper stratosphere and lower mesosphere.