Influence of isentropic transport on seasonal ozone variations in the lower stratosphere and subtropical upper troposphere

摘要: [1] The isentropic cross-tropopause ozone transport has been estimated in both hemispheres 1999 based on the potential vorticity mapping of Stratospheric Aerosol and Gas Experiment II measurements contour advection calculations using NASA Goddard Space Flight Center Global Modeling Assimilation Office analysis. The net stratosphere-to-troposphere flux is ∼118 ± 61 × 109 kg yr−1 globally within layer between 330 370 K 1999; 60% it found Northern Hemisphere, 40% Southern Hemisphere. monthly average fluxes are strongest summer weakest winter hemispheres. seasonal variations lower stratosphere (LS) upper troposphere (UT) have analyzed ozonesonde observations from stations extratropics subtropics, respectively. It shown that observed levels increase UT over subtropical decrease LS extratropical late spring/early increases summertime unlikely to be explained by photochemical production diabatic alone. We conclude a significant contributor troposphere, especially summer.