Atmos. Chem. Phys. Discuss., 9, 17937-17962, 2009
www.atmos-chem-phys-discuss.net/9/17937/2009/
doi:10.5194/acpd-9-17937-2009
© Author(s) 2009. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP.
Annual cycle of ozone at and above the tropical tropopause: observations versus simulations with the Chemical Model of the Stratosphere (CLaMS)
P. Konopka1, J.-U. Grooß1, G. Günther1, F. Plöger1, R. Pommrich1, R. Müller1, and N. Livesey2
1Forschungszentrum Jülich (ICG-1: Stratosphere), Germany
2Jet Propulsion Laboratory, California Institue of Technology, Pasadena, CA, USA

Abstract. Multi-annual simulations with the Chemical Model of the Stratosphere (CLaMS) are used to study the seasonality of O3 and of the mean age within the stratospheric part of the tropical tropopause layer (TTL) In agreement with satellite (HALOE) and in-situ observations (SHADOZ), CLaMS simulations show above ≈360 K potential temperature, a pronounced annual cycle in O3 and in the mean age of air with highest values in the late boreal summer. Within the model, this seasonality is driven by the seasonality of both upwelling and in-mixing. The latter process describes enhanced meridional transport from the extratropics into the TTL. The strongest in-mixing occurs from the Northern Hemisphere during the boreal summer in the potential temperature range between 380 and 420 K. Contrary, an increase of upwelling with highest values in winter reduces O3 up to the lowest values in early spring. Both, CLaMS simulations and Aura MLS O3 observations show that this enhanced equatorward transport in summer is mainly driven by the Asian monsoon anticyclone.

Citation: Konopka, P., Grooß, J.-U., Günther, G., Plöger, F., Pommrich, R., Müller, R., and Livesey, N.: Annual cycle of ozone at and above the tropical tropopause: observations versus simulations with the Chemical Model of the Stratosphere (CLaMS), Atmos. Chem. Phys. Discuss., 9, 17937-17962, doi:10.5194/acpd-9-17937-2009, 2009.
 
Search ACPD
Discussion Paper
    XML
    Citation
    Final Revised Paper
    Share