AN ISENTROPIC 2-DIMENSIONAL MODEL WITH AN INTERACTIVE PARAMETRIZATIONOF DYNAMICAL AND CHEMICAL PLANETARY-WAVE FLUXES

An interactive chemical-dynamical isentropic two-dimensional model is described, and its behaviour analysed when a parametrization of the th ree longest Rossby waves is included in the model. Eddy fluxes of chem icals and of Ertel's potential vorticity are all calculated from the m odelled waves, and are therefore consistent with each other. The chemi cal fluxes arise from dissipation of zonal asymmetries, both by photoc hemistry ('chemical eddy' fluxes) and by 'planetary wave breaking'. Th e chemical eddy fluxes for ozone and NO(y) are much larger than the wa ve-breaking ones, and thus the diffusion matrix (which has only one no n-zero clement) is far from being independent of chemical species. The waves have a large immediate effect on the ozone distribution, but th e effect persists throughout the year only when the wave fluxes induce a persistent change in the photochemical equilibrium state for ozone (mainly by changing NO(x)).