Relationships between Brewer-Dobson circulation, double tropopauses, ozone and stratospheric water vapour 1CESAM, Department of Physics, University of Aveiro, Portugal
06 Nov 2012
2National Center for Atmospheric Research, Boulder, Colorado, USA
3Center for Limb Atmospheric Sounding, University of Colorado at Boulder, Boulder, Colorado, USA
4Goddard Earth Sciences Technology and Research, Morgan State University, Baltimore, Maryland, USA
Received: 31 Mar 2012 – Published in Atmos. Chem. Phys. Discuss.: 15 May 2012 Abstract. Statistical relationships between the variability of the area covered by
double tropopause events (DTs), the strength of the tropical upwelling, the
total column ozone and of the lower stratospheric water vapour are analyzed.
The QBO and ENSO signals in the double tropopause and tropical upwelling as
well as their influence on the statistical relationships are also presented.
The analysis is based on both reanalysed data (ERA-Interim) and satellite
Revised: 24 Oct 2012 – Accepted: 29 Oct 2012 – Published: 06 Nov 2012
Significant anticorrelations were found between the area covered by DTs and
the total column ozone in the midlatitudes of the Northern Hemisphere. This
relationship is confirmed by a large positive correlation between the areas
covered by ozone laminae and double tropopause events as found in the HIRDLS
satellite dataset. Significant anticorrelations were also found between the
global area of double tropopause events and the near global
(50° S–50° N) water vapour in the lower stratosphere.
The correlations of DT variables with total column ozone and ozone laminae
are both consistent with the poleward displacement of tropical air with lower
ozone mixing ratio and with tropospheric intrusions of tropical tropospheric
air into the lower extratropical stratosphere. The association of DTs with
the poleward displacements of the tropical air is also consistent with a
strong positive correlation between the area covered by DTs and the wave
activity in the lower most stratosphere, between the first and second lapse
rate tropopauses, as found in the ERA-Interim reanalysis.
Finally, a significant anticorrelation was found between the tropical
upwelling and the near global lower stratospheric water vapour. Moreover, the
step like decrease in the lower stratospheric water vapour after 2001 is
mirrored by a step like increase in the tropical upwelling.
Citation: Castanheira, J. M., Peevey, T. R., Marques, C. A. F., and Olsen, M. A.: Relationships between Brewer-Dobson circulation, double tropopauses, ozone and stratospheric water vapour, Atmos. Chem. Phys., 12, 10195-10208, doi:10.5194/acp-12-10195-2012, 2012.