Impact of stratospheric ozone on Southern Hemisphere circulation change: A multimodel assessment

S.-W. Son. (1) , E. P. Gerber (2) , J. Perlwitz (3, 4) , L. M. Polvani (5, 6) , N. P. Gillett (7) , K.-H. Seo (8) , V. Eyring (9) , T. G. Shepherd (10) , D. Waugh (11) , H. Akiyoshi (12) , J. Austin (13) , A. Baumgaertner (14) , Slimane Bekki (15) , P. Braesicke (16) , C. Bruhl (14) , N. Butchart (17) , M. P. Chipperfield (18) , David Cugnet (15) , M. Dameris (9) , S. Dhomse (18) , S. Frith (19) , H. Garny (9) , R. Garcia (20) , S. C. Hardiman (17) , P. Jockel (9, 14) , J. F. Lamarque (20) , E. Mancini (21) , Marion Marchand (15) , M. Michou (22) , T. Nakamura (12) , Olaf Morgenstern (23, 16) , G. Pitari (21) , D. A. Plummer (7) , J. Pyle (16) , E. Rozanov (24, 25) , J. F. Scinocca (7) , K. Shibata (26) , Dan Smale (23) , H. Teyssedre (22) , W. Tian (18) , Y. Yamashita (12)

1 Department of Atmospheric and Oceanic Sciences [Montréal]
2 CAOS - Center for Atmosphere Ocean Science [NYU]
3 ESRL - NOAA Earth System Research Laboratory
4 CIRES - Cooperative Institute for Research in Environmental Sciences
5 Department of Applied Physics and Applied Mathematics [New York]
6 Department of Earth and Environmental Sciences [New York]
7 CCCma - Canadian Centre for Climate Modelling and Analysis
8 Department of Atmospheric Sciences [Busan]
9 IPA - DLR Institut für Physik der Atmosphäre = DLR Institute of Atmospheric Physics
10 Department of Physics [Toronto]
11 JHU - Johns Hopkins University
12 NIES - National Institute for Environmental Studies
13 GFDL - NOAA Geophysical Fluid Dynamics Laboratory
14 MPIC - Max-Planck-Institut für Chemie
15 STRATO - LATMOS
16 NCAS-Climate [Cambridge]
17 United Kingdom Met Office [Exeter]
18 SEE - School of Earth and Environment [Leeds]
19 GSFC - NASA Goddard Space Flight Center
20 NCAR - National Center for Atmospheric Research [Boulder]
21 UNIVAQ - University of L'Aquila [Italy]
22 CNRM - Centre national de recherches météorologiques
23 NIWA - National Institute of Water and Atmospheric Research [Lauder]
24 PMOD/WRC - Physikalisch-Meteorologisches Observatorium Davos/World Radiation Center
25 IAC - Institute for Atmospheric and Climate Science [Zürich]
26 MRI - Meteorological Research Institute [Tsukuba]

The impact of stratospheric ozone on the tropospheric general circulation of theSouthern Hemisphere (SH) is examined with a set of chemistry‐climate models participatingin the Stratospheric Processes and their Role in Climate (SPARC)/Chemistry‐ClimateModel Validation project phase 2 (CCMVal‐2). Model integrations of both the past andfuture climates reveal the crucial role of stratospheric ozone in driving SH circulationchange: stronger ozone depletion in late spring generally leads to greater polewarddisplacement and intensification of the tropospheric midlatitude jet, and greater expansion ofthe SH Hadley cell in the summer. These circulation changes are systematic as polewarddisplacement of the jet is typically accompanied by intensification of the jet and expansion ofthe Hadley cell. Overall results are compared with coupled models participating in theIntergovernmental Panel on Climate Change Fourth Assessment Report (IPCC AR4), andpossible mechanisms are discussed. While the tropospheric circulation response appearsquasi‐linearly related to stratospheric ozone changes, the quantitative response to a givenforcing varies considerably from one model to another. This scatter partly results fromdifferences in model climatology. It is shown that poleward intensification of the westerly jetis generally stronger in models whose climatological jet is biased toward lower latitudes.This result is discussed in the context of quasi‐geostrophic zonal mean dynamics.

Mots clés: CCMVal-2; Southern Hemisphere climate change; Ozone hole

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

S.-W. Son., E. P. Gerber, J. Perlwitz, L. M. Polvani, N. P. Gillett, et al.. Impact of stratospheric ozone on Southern Hemisphere circulation change: A multimodel assessment. Journal of Geophysical Research: Atmospheres, 2010, 115 (D3), pp.D00M07. ⟨10.1029/2010JD014271⟩. ⟨hal-00510592⟩