Troposphere stratosphere

FIGURE 12.3 Schematic of wave-driven extratropical pump that drives global-scale transport from the tropical troposphere to the stratosphere and then poleward. Three possible paths for stratosphere-troposphere exchange (STE) are shown. (Adapted from Holton et al., 1995.)... 

In short, exchange of air between the Northern and Southern Hemispheres is slow, as is that between the troposphere and stratosphere, both being on the time scale of about a year (Warneck, 1988). The mechanisms of stratosphere-troposphere exchange are complex but a detailed understanding of these is critical to the assessment of the atmospheric fates of many species, particularly those emitted in the lowermost stratosphere. For reviews of these processes, see Holton et al. (1995), Salby and Garcia (1990), and Mahlman (1997) and for some relevant studies, Langford et al. (1996) and Folkins and Appenzeller (1996). 

MODEL ANALYSIS OF STRATOSPHERE-TROPOSPHERE EXCHANGE OF OZONE AND ITS ROLE IN THE TROPOSPHERIC OZONE BUDGET... 

Holton, J.R., and Lelieveld, J. (1996) Stratosphere-troposphere exchange and its role in the budget of tropospheric ozone, in P.J. Crutzen and V. Ramanathan (Eds.), Clouds, Chemistry and Climate, NATO ASI Series, Springer-Verlag, Berlin, pp. 173-190. 

Vaughan, G. (1988) Stratosphere-troposphere exchange of ozone, In I.S.A Isaksen (Ed.) Tropospheric ozone, D. Reidel, Dordrecht, pp. 125-135. 

Ebel, A., Elbern, H., and Oberreuter, A. (1993) Stratosphere-troposphere air mass exchange and cross-tropopause fluxes of ozone, in E.V. Thane (Ed.), Coupling processes in the lower and middle atmosphere, Kluwer, Dordrecht, pp. 49-65. 

Kentarchos, A.S., Roelofs, G.J., and Lelieveld, J. (1999) Simulation of extratropical synoptic scale stratosphere-troposphere exchange using a coupled chemistry-GCM Sensitivity to horizontal resolution, submitted to J. Atm. Sci. 

Kiehl, J.T. and Boville, B.A. (1988) The radiative-dynamical response of a stratospheric-tropospheric general circulation model to changes in ozone. J. Atmos. Sci. 45, pp. 1798-1817. 

STIB Study of interactions in the stratosphere-troposphere-biosphere system. 

Stratosphere Troposphere Interactions and the Biosphere A global 3-D Lagrangian chemistry transport model Scientific and Technical Translation... 

Danielsen E.F., Stratospheric tropospheric exchange based on radioactivity, ozone, and potential vorticity. J. Atmos. Sci., 25, 4495-4498 (1968). 

Another important application of the CO2 isotopic measurements is their use as a measure of stratosphere-troposphere mixing. Stratospheric CO2 is mass-independently fractionated due to its coupling with ozone, while tropospheric is mass dependent because of its equilibrium with water. As originally described by Urey (1947), this is a purely mass-dependent process and has been confirmed by laboratory measurements (Thiemens et al., 1995). This feature provides an ideal marker for the two individual atmospheric reservoirs. 

Semb, A. Proc. WMO svmp. lonq-ranae transport of pollutants and it relation, t.9 qeney l ciiculfttioh jnsiuging stratospheric/tropospheric exchange process. WMO No. 538, pp. la-lm, Geneva, 1979. 

Figure 3.30. Schematic representation of the atmospheric circulation (arrows) and associated quasi-horizontal mixing between the surface and the middle stratosphere. Mixing processes leading to stratosphere-troposphere exchanges are also represented. The heavy vertical lines denote dynamical barriers against meridional transport. Note the large-scale ascent in the tropical stratosphere above intense convective systems in the tropical troposphere, and large scale descent associated with the polar vortex during winter (WMO, 1999).

Kodera, K., and Y. Kuroda, A mechanistic model study of slowly propagating coupled stratosphere-troposphere variability. J Geophys Res 105, 12,361, 2000b. 

Table 1-10. Individual Processes and Their Contributions (Fraction of Stratospheric Air Mass) to the Air Exchange across the Tropopause (Stratosphere- Troposphere)...

Mohnen (1977), based on earlier work of Danielsen (1964, 1968) and Reiter (1975) 320 -470 Stratospheric-tropospheric air mass exchange tropopause folding events plus large-scale Hadley circulation m(03) = 1.3 pg/g assumed. 

Reiter, E. R., M. E. Glasser, and J. D. Mahlman (1969). The role of the tropopause in stratospheric-tropospheric exchange processes. Pure Appl. Geophys. 12, 183-221. 

---