Open AccessQBO and annual cycle variations in tropical lower stratosphere trace gases from HALOE and Aura MLS observations
Author(s) -
Schoeberl M. R.,
Douglass A. R.,
Newman P. A.,
Lait L. R.,
Lary D.,
Waters J.,
Livesey N.,
Froidevaux L.,
Lambert A.,
Read W.,
Filipiak M. J.,
Pumphrey H. C.
Publication year - 2008
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2007jd008678
Subject(s) - tropopause , stratosphere , trace gas , annual cycle , quasi biennial oscillation , atmospheric sciences , environmental science , ozone , climatology , forcing (mathematics) , physics , meteorology , geology
We have analyzed thirteen years (1993 to 2005) of HALOE and over two years of EOS MLS observations (September 2004 to December 2006) for QBO and annual cycle trace variations in tropical H 2 O, HCl, ozone, N 2 O, CO, HF, and CH 4 . We use these results to develop the theory explaining both Brewer‐Dobson circulation (BDC) and QBO driven fluctuations in tropical trace gases. For H 2 O, BDC variations drive part of the tropopause annual forcing through annual variations in the temperature as has been shown previously. For CO, the annual variations in the BDC amplify the annual fluctuations in CO at the tropopause as has recently been shown by Randel et al (2007). In both cases, the tropopause signal is carried upward by the mean BDC. For ozone, N 2 O, HCl and other gases, photochemical processes force fluctuations in the trace gases to be synchronized with annual and QBO variations in the zonal mean residual vertical velocity as is shown using lag correlations.