Evolution of the eastward shift in the quasi-stationary minimum of the Antarctic total ozone column

Asen Grytsai,Andrew Klekociuk,Gennadi Milinevsky,Oleksandr Evtushevsky,Kane Stone

doi:10.5194/acp-17-1741-2017

Abstract

Abstract. The quasi-stationary pattern of the Antarctic total ozone has changed during the last 4 decades, showing an eastward shift in the zonal ozone minimum. In this work, the association between the longitudinal shift of the zonal ozone minimum and changes in meteorological fields in austral spring (September–November) for 1979–2014 is analyzed using ERA-Interim and NCEP–NCAR reanalyses. Regressive, correlative and anomaly composite analyses are applied to reanalysis data. Patterns of the Southern Annular Mode and quasi-stationary zonal waves 1 and 3 in the meteorological fields show relationships with interannual variability in the longitude of the zonal ozone minimum. On decadal timescales, consistent longitudinal shifts of the zonal ozone minimum and zonal wave 3 pattern in the middle-troposphere temperature at the southern midlatitudes are shown. Attribution runs of the chemistry–climate version of the Australian Community Climate and Earth System Simulator (ACCESS-CCM) model suggest that long-term shifts of the zonal ozone minimum are separately contributed by changes in ozone-depleting substances and greenhouse gases. As is known, Antarctic ozone depletion in spring is strongly projected on the Southern Annular Mode in summer and impacts summertime surface climate across the Southern Hemisphere. The results of this study suggest that changes in zonal ozone asymmetry accompanying ozone depletion could be associated with regional climate changes in the Southern Hemisphere in spring.

Highlights

The distribution of total column ozone over Antarctica is significantly non-uniform during austral spring, i.e., in September–November (Wirth, 1993; Malanca et al, 2005; Grytsai et al, 2007a; Agosta and Canziani, 2010, 2011)
We compare the long-term changes in total ozone (Fig. 2a) and the longitudinal position of the quasi-stationary ozone minimum (Fig. 2b) at 65◦ S latitude, which is located in the edge region of the ozone hole and polar stratospheric vortex (Roscoe et al, 2012) and where the largest quasi-stationary wave (QSW) amplitude is observed (Grytsai et al, 2007a; Ialongo et al, 2012)
We have examined the variability of the minimum in the quasi-stationary pattern in total column ozone in spring at high southern latitudes using observations and model simulations

Summary

Introduction

The distribution of total column ozone over Antarctica is significantly non-uniform during austral spring, i.e., in September–November (Wirth, 1993; Malanca et al, 2005; Grytsai et al, 2007a; Agosta and Canziani, 2010, 2011). This has been the case since the early 1980s due to the presence of ozone depletion associated with the ozone hole (Chubachi, 1984; Farman et al, 1985; Chubachi and Kajiwara, 1986; Stolarski et al, 1986; Solomon, 1999). The polar vortex is under the influence of large-scale planetary waves, which disturb the vortex edge region

Results

Discussion

Conclusion