This session will focus on the interplay between chemistry and dynamics in the global tropopause region including coupling between the tropical and the extratropical tropopause region. Observational as well as theoretical and model based contributions are invited, in particular synergistic combinations of observations, models, and/or theory. Relevant topics include cross tropopause exchange, transport pathways and timescales for chemical constituents as well as dynamical and radiative processes and their timescales in the global UTLS.
Special emphasis will be given on the interaction between chemical composition and the dynamical structure of the UTLS (e.g. as relevant for the tropopause inversion layer or the tropical tropopause layer). This includes contributions focusing on
1.Chemical and dynamical structure of the UTLS
2.Relevant dynamical, radiative, and chemical timescales
3.Long-term variability and trends of chemistry and/or dynamics in the UTLS