The impact of polar stratospheric ozone loss resulting from chlorineactivation on polar stratospheric clouds is examined using a pair of modelintegrations run with the fully coupled chemistry climate model UM-UKCA.Suppressing chlorine activation through heterogeneous reactions is found toproduce modelled ozone differences consistent with observed ozonedifferences between the present and pre-ozone hole period. Statisticallysignificant high-latitude Southern Hemisphere (SH) ozone loss begins inAugust and peaks in October–November, with > 75% of ozonedestroyed at 50 hPa. Associated with this ozone destruction is a> 12 K decrease of the lower polar stratospheric temperatures andan increase of > 6 K in the upper stratosphere. The heatingcomponents of this temperature change are diagnosed and it is found that thetemperature dipole is the result of decreased short-wave heating in the lowerstratosphere and increased dynamical heating in the upper stratosphere. Thecooling of the polar lower stratosphere leads, through thermal wind balance,to an acceleration of the polar vortex and delays its breakdown by~ 2 weeks. A link between lower stratospheric zonal windspeed, the vertical component of the Eliassen–Palm (EP) flux, and the residual meanvertical circulation, *, is identified. In November andDecember, increased westerly winds and a delay in the breakup of the polarvortex lead to increases in , indicating increased wave activityentering the stratosphere and propagating to higher altitudes. The resultingincrease in wave breaking, diagnosed by decreases to the EP flux divergence,drives enhanced downwelling over the polar cap. Many of the stratosphericsignals modelled in this study propagate down to the troposphere, and leadto significant surface changes in December.
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