Prescribing stratospheric chemistry overestimates southern hemisphere climate change during austral spring in response to quadrupled CO2

The interaction of stratospheric chemistry with a changing climate from an abrupt CO2 quadrupling is assessed using the coupled atmosphere–ocean Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). Two 4 × experiments were performed, one interactive and other prescribed that does not simulate ozone response to CO2. similar global mean surface temperature change. Nevertheless, critical capture Southern Hemisphere tropospheric midlatitude jet When neglected, GEOSCCM overestimates circulation This chemistry-induced impact has large seasonal variability. During austral spring season September–October–November (SON), yields stronger poleward shift intensification jet, wind stress, Ocean meridional overturning than occurs chemistry. In seasons have effects on circulation. seasonality related Antarctic lower contrast this CO2, recovery decline depleting substances its largest in summer (December–January–February), but no SON. It found different for these two layer change scenarios tropopause gradient response.