Thisstudycomparestheclimatologyandlong-termtrendofnorthernwinterstratosphericresidualmeanmeridionalcirculation(RMMC),aswellasitsresponsestoElNi?o-SouthernOscillation(ENSO),stratosphericQuasiBiennialOscillation(QBO),andsolarcycleintenreanalysesandastratosphere-resolvingmodel,CESM1-WACCM.TheRMMCisalarge-scalemeridionalcirculationcellinthestratosphere,usuallyreferredtoastheestimateoftheBrewerDobsoncirculation(BDC).ThedistributionoftheBDCisgenerallyconsistentamongmultiplereanalysesexceptthattheNOAAtwentiethcenturyreanalysis(20RC)largelyunderestimatesit.Mostreanalyses(exceptERA40andERA-Interim)showastrengtheningtrendfortheBDCduring1979–2010.AllreanalysesandCESM1-WACCMconsistentlyrevealthatthedeepbranchoftheBDCissignificantlyenhancedinElNi?owintersasmorewavesfromthetropospheredissipateinthestratosphericpolarvortexregion.AsecondarycirculationcelliscoupledtothetemperatureanomaliesbelowtheQBOeasterlycenterat50hPawithtropicalupwelling/coolingandmidlatitudedownwelling/warming,andsimilarsecondarycirculationcellsalsoappearbetween50–10hPaandabove10hPatobalancethetemperatureanomalies.ThedirectBDCresponsetoQBOintheupperstratospherecreatesabarriernear30°Ntopreventwavesfrompropagatingtomidlatitudes,contributingtotheweakeningofthepolarvortex.TheshallowbranchoftheBDCinthelowerstratosphereisintensifiedduringsolarminima,andthedownwellingwarmstheArcticlowerstratosphere.ThestratosphericresponsestoQBOandsolarcycleinmostreanalysesaregenerallyconsistentexceptinthetwo20CRs.
