The Response of Tropospheric Circulation to Perturbations in Lower-Stratospheric Temperature

• DOI: 10.1175/jcli3472.1
• Publication Date: 2005-10-06T21:02:50Z
• Authors: Joanna D. Haigh; Michael Blackburn; Rebecca Day
• Keywords: Hadley cell; Atmospheric Circulation; Forcing (mathematics); Middle latitudes; Quasi-biennial oscillation

Abstract A multiple regression analysis of the NCEP–NCAR reanalysis dataset shows a response to increased solar activity weakening and poleward shift subtropical jets. This signal is separable from other influences, such as those El Niño–Southern Oscillation (ENSO) North Atlantic (NAO), very similar that seen in previous studies using global circulation models (GCMs) effects an increase spectral irradiance. The stratospheric (volcanic) aerosol found data be equatorward GCM influence also showed impact on tropospheric mean meridional with expansion tropical Hadley cells Ferrel cells. To understand mechanisms whereby changes irradiance affect winds circulation, experiments have been carried out simplified model. results show generic heating lower stratosphere tends weaken jets circulations. positions jets, extent cells, respond distribution heating, low-latitude forcing them move poleward, high-latitude or latitudinally uniform equatorward. patterns are result volcanic respectively, analysis. demonstrates perturbations heat balance stratosphere, brought about by activity, can produce even without any direct below tropopause.