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Associations between the wintertime northpole temperatures, QBO, and the 11-yr solarcycle in CMIP5 historical runs forced with theSOLARIS solar spectral irradianceShingo WatanabeResearch Institute for Global Change/ Japan Agency for Marine-EarthScience and Technology (JAMSTEC)SOLARIS Workshop 10-12/03/2010


Background and motivationSOLARIS WorkshopLabitzke et al. (2006)10-12/03/2010• Are these relationshipsreproduced in our CMIP5historical (1850-2005)experiments?• If yes,▫ Mechanisms??▫ Past and future??Matthes et al. (2004)


10-12/03/2010Model and Experimental DesignsSOLARIS Workshop• MIROC-ESM(T42L80AGCM+1degOGCM)• CMIP5-historical exp (1850-2005)▫ With CCM – 1member▫ With GCM – 3 members• RCP’s historical scenario forconcentration/emission/land use• CO2 concentration is prescribed• Other GHGs including O3 are▫ predicted in CCM▫ prescribed in GCM(The prescribed O3 in GCM doesnot contain the 11-yr solar cycle.)• Volcanic aerosols (Sato et al., GISS)▫ Optical thickness (τ) is given toradiation in CCM and GCM▫ Sulfate SAD reconstructed from τ isgiven to CCM• SOLARIS solar spectra▫ into 23 bands (VIS+UV) in CCM▫ into 15 bands (VIS+UV) in GCM▫ Additional SRB calculations only forphotochemistry: 15bands in CCM▫ Lyman-α for H2O in CCM• QBO▫ Spontaneously generated usingHines’s GWD parameterization▫ Constant GW source is giventhroughout 1850-2005, which istuned so that realistic period isobtained in 2000’s condition.CCM: Sudo et al., to be submitted to Geosci. Model Dev.ESM:Watanabe et al., to be submitted to Geosci. Model Dev.


Basic resultsSOLARISWorkshop 10-12/03/2010ERA40(global mean)MIROC-ESM-CHEMWatanabe et al., to be submitted to Geosci. Model Dev.


Zonal wind climatologySOLARIS Workshop 10-12/03/20100.030.1110100OCT NOV DECJAN FEB MAR1000SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP0.030.11101001000SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NPMet Office CIRA861994-2001 75/76-77/78MIROC-ESM-CHEM1950-2000


Solar cycle in UV fluxCCM UV=185-355nm 10bandsGCM UV=200-333nm 4bandsSOLARIS Workshop10-12/03/2010NOV/DEC mean UVflux anomaly is used fora solar-cycle index,because UV heating inearly winter is likelyimportant. (e.g., Koderaand Kuroda, 2002)11-year running average was subtracted fromthe original time series to make an indexincluding almost the same number of Solarmin/Solar-max


CCM 1950-2000JAN+FEB mean NP30hPa-TNP (J+F)/2 30hPa-T-52vs. QBO vs. UV-anomalyE (23)W(28)-80-80-24 EQ 30hPa-U16 -0.20.2UV ANOMALYNP (J+F)/2 30hPa-T-52EWSOLARIS WorkshopW10-12/03/2010R(W)=0.14R(E)=-0.57☺ Holton –Tan’s relationship is evident especially in Solar-min.☺Negative correlation between T and UV in QBO-E coincides with Obs.Less warmings occurred in QBO-W and Solar-max compared to Obs.


CCM 1950-2000JAN+FEB mean NP30hPa-TNP (J+F)/2 30hPa-T-52vs. QBO vs. UV-anomalyE (23)W(28)-80-80-24 EQ 30hPa-U16 -0.20.2UV ANOMALYLabitzke and van Loon (1992)NP (J+F)/2 30hPa-T-52EWSOLARIS WorkshopW10-12/03/2010R(W)=0.14R(E)=-0.57☺ Holton –Tan’s relationship is evident especially in Solar-min.☺Negative correlation between T and UV in QBO-E coincides with Obs.Less warmings occurred in QBO-W and Solar-max compared to Obs.


SOLARIS Workshop 10-12/03/2010Composite differences in Solar-min betweenQBO W-E; showing the Holton-Tan’s relationshipsDEC JAN FEBT 2K• Effects of other variability dueto▫ Volcanic aerosols▫ ENSO▫ Increasing GHGsare not distinguished in thepresent composite analyses.• Statistical significance will bechecked someday.▫ NQBO-E = 14▫ NQBO-W = 13U 2ms -1SP EQ NP SP EQ NP SP EQ NPPNJ is stronger in QBO-W.Westerly anomalypropagates poleward anddownward.


SOLARIS Workshop 10-12/03/2010Composite differences between Solar Max-MinSmax=9QBO-E QBO-WSmin=14DEC JAN FEBSmax=15Smin=13DEC JAN FEBlikely notsignificantT 2KU 2ms -1In solar maximums, westerlyanomaly initiated in thesubtropics propagatespoleward and downward.T 2KCompared to observationalanalyses in Matthes et al (2004);The initial intensification of thesubtropical jet is much weaker.The propagation andintensification of the westerlyanomaly occurs morecontinuously.Tropospheric anomaly is small.U 2ms -1SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP


SOLARIS WorkshopComposite differences; Solar Max-MinSmax=9QBO-E QBO-WSmin=14DEC JAN FEB10-12/03/2010Smax=15Smin=13DEC JAN FEBlikely notsignificantMore warming eventsoccur in DEC and JAN ofT 2KSolar-max.In analyses of Matthes et al. (2004),SJ and PNJ is strong in earlywinter of Solar-max, then suddenwarmings preferentially occur inFEB.T 2KU 2ms -1U 2ms -1SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP SP EQ NP


SummarySOLARISWorkshop 10-12/03/2010• The 1950-2000 period of CMIP5 historical experiment ofMIROC-ESM-CHEM (CCM) has been analyzed.• Associations between the northern winter zonal winds andtemperatures, QBO wind phases, and UV fluxes were (briefly)investigated.• Holton-Tan’s relation was evident in Solar-min like that inobservations.• PNJ was stronger in Solar-max when QBO was Easterly.• Poleward and downward propagation of zonal wind anomalywas seen, but changes in the troposphere were small.• (Possible mechanisms, i.e. wave-mean flow interactions andchanges in mean meridional circulations, will be investigatedin the near future.)• Less stratospheric warmings occurred during late winters ofSolar-max and QBO-W, compared to observations.• Abovementioned solar effects are neither evident in otherperiods of the CCM experiment nor in GCM ensembles.


CCMless UVvariationSOLARIS Workshop10-12/03/20101860-1899 1900-1949less UVvariation1950-2000 RCP4.5 2001-2050


GCM 3-member ensembleSOLARISWorkshop 10-12/03/20101860-1899 1900-1949E(60)W(60)E(76)W(74)1950-2000 RCP4.5 2001-2050E(76)W(77)E(26)W(24)

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