The evolution of zonally asymmetric austral ozone in a chemistry–climate model

Atmospheric Chemistry and Physics (2017)

We investigate the simulation of the zonal asymmetry in Southern Hemisphere stratospheric ozone in the NIWA-UKCA atmosphere–ocean chemistry–climate model using elliptical diagnostics. During spring, the region most depleted in ozone is displaced from the pole toward South America based on ERA-Interim and the model output.

The model correctly simulates the direction of this displacement but significantly underestimates its magnitude. Comparison with model runs in which ozone-depleting substances are held fixed at pre-ozone-hole levels shows that this shift is primarily a function of the magnitude of ozone depletion, although increases in greenhouse gases also have some effect.