Two long meridional flights of the WB57F high-altitude aircraft 1--2 km below the tropical tropopause are examined for ozone and total water variability in the context of a large suite of tracers having lifetimes ranging from 10-2 to 103 years, together with mass spectra of individual aerosol particles. It is concluded that local correlations are predominant; contributing processes to the maintenance of the composition are marine convection, continental convection, in situ chemical production, biomass burning, downward transport from the stratosphere and recirculation.