Ozone-Circulation Interaction in the Stratosphere  It is well known that interactive ozone, in which ozone evolves in dynamically consistent ways with the circulation, improves model simulations of climate. By capturing the feedbacks between ozone and the circulation, interactive ozone intensifies the coupling between the stratosphere and troposphere and leads to more pronounced climate trends. We explore the effects of interactive ozone with a relatively simple chemistry-climate model (SCCM). The model solves the primitive equations, contains a linear ozone scheme, and parameterizes the shortwave radiative heating from ozone. Two long simulations are performed: first, a control run with fully interactive ozone (SCCM run), and a second run with prescribed ozone (PrO3 run) using daily ozone climatology from the interactive run. By comparing the two simulations, we find that interactive ozone increases the interannual variability of the stratosphere and troposphere during spring over the Arctic. The increased variability can be attributed to the response of ozone to extreme wintertime stratospheric circulation events (sudden stratospheric warmings, SSWs, and vortex intensification events, VIs) and the prolongation of the events by the anomalous ozone heating. The downward coupling of the more persistent events into the troposphere implies improved predictability on subseasonal to seasonal time scales.