Downward influence exerted by longitudinal variations in stratospheric ozone

The downward influence exerted by longitudinal variations in stratospheric ozone (LVSO) is examined using a mechanistic model that self-consistently couples dynamics, radiative transfer, and the transport and photochemistry of ozone. The model describes the time-height evolution of the zonal-mean and wave portions of the wind, temperature and ozone fields. The LVSO is shown to induce a zonal-mean body force, measured by the divergence of Eliassen-Palm flux, which affects local wave-mean flow interaction and the residual circulation. Because the one-dimensional model framework confines the waves to propagate solely in the vertical, a stratospheric reflecting region is required for the planetary wave-induced ozone heating in the stratosphere to produce non-local changes in the residual vertical velocity. Using WKB methods and numerical simulations, the relative importance of local wave-mean flow interaction, downward control and planetary wave reflection in producing downward propagating signals is examined for two ozone scenarios: (1) interactive ozone chemistry and (2) prescribed ozone chemistry. The effects of longitudinal variations in stratospheric ozone on tropospheric climate are discussed in light of human-caused and naturally-induced perturbations in stratospheric ozone.