Under this award, the principal investigator will couple two existing models: a quasi-geostrophic time-dependent wave model of the stratosphere with a zonally averaged (two- dimensional) chemical-radiative-dynamical model of the middle atmosphere. By coupling the two, it is hoped that the better representation of the large-scale structure and wave-mean flow interaction in the stratosphere will provide more realistic estimates of transport and the mean distribution of trace chemical species in the middle atmosphere. Further, the study may provide clues as to how best to parameterize some of the planetary wave and eddy effects in the two-dimensional chemical model. The complexity and vast computational requirements of three-dimensional models makes the option of conducting certain studies with simpler two-dimensional models very attractive. This project has the potential to improve the (now) crude parameterizations of wave interactions in existing two- dimensional models.