大气季节内振荡对印度洋—西太平洋地区热带低压气旋生成的影响

/X(,100081;,LASG,,100029)TetsuoNakazawa(,Tsukuba305-0051)(LASG,,100029)EOF(MJO),1996919976MJO/,,/MJOMJO,/,/MJO:(MJO),EOF,/1(Madden2JulianOscillation,MJO),,3060d[13],MJO,MJO-[46],[79],[1012],MJO(TC)Nakazawa[13],TCMJO,MJO,MJO3000kmTC,MJOTC[14],Lieb2mann[15],MJOTC,TC(TD),MJOTC,,Hall[16]20aTCMJO,TCMJOMJOTC,TC,MJO(),()MJO4[17],3060d3090dMJO,MJO,MJO,,62120042ACTAMETEOROLOGICASINICAVol.62,No.1February2004X:200333;:2003731:(40375014)LASG©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.MJO,MJO/,MJO,MJOTD/TC2TD/TC(JointTyphoonWarningCenter,JTWC),6hTCZehr[18],JTWC117m/s(TD)(TC),100135E,41996919976,TDTC7166,25S25N(1),TDTC5,18TD30,TC25;TDTC1811996919976/(TDTC)Fig.1MapofTD/TCpositionsfrom1September1996to30June1997intheIndian2WesternPacificOceans(ThecrossmarkdenotesTD,andtheTCismarkedbyopencircle),NOAA(OLR)NCEP/NCAR,2.52.5,1996819976,19902000:19971998ENSO19974,12,EN2SO,19971998ENSOMJO[19]199746ENSO,ENSO3MJO,OLR3060d3090dMJO,MJO,MJO,Matthews[20]25S25NOLR,20200dOLREOF,3060dEOFMJO,EOFMJO(,)MJOTD/TC,OLR30S30N40E60W,20120dOLREOF,MJOMatthews[22],20120dOLREOFMJOMJOtZ341:/©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.Z(t)=[PC1(t),PC2(t)](1),PC1PC2EOF1EOF2MJOA(t):A(t)=[P2C1(t)+P2C2(t)]1/2(2)PC1PC2(t):(t)=tan-1[PC2(t)/PC1(t)](3)2,20120dOLREOF,EOF,EOF1120E2199681997620120dOLREOF(a.EOF1,b.EOF2,5W/m2,,c.EOF1EOF2PC1()PC2(),d.(,)A(,))Fig.2Empiricalorthogonalfunctionanalysisof20120daysfilteredOLR(a.EOF1,b.EOF2,contourintervalis5W/m2;thezerocontourisomitted;shadingisshownbythelegend,c.PC1(solidline)andPC2(dashedline)fortheperiodofAugust1996toJune1997,d.Phase(dashed;scaleontheright2handaxis)anddailyamplitudeA(solidline;scaleontheleft2handaxis)ofZfrom1August1996to30June1997)4462©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.,EOF1,EOF2,,EOF[20],EOF1EOF2,15.59%11.31%,EOF36.83%,EOFEOF1PC1EOF2PC21/4,3060dEOF1EOF2,EOFMJO19968199766MJO,,1996910199712,MJO,MJOMJO,MJOEOF,PC1PC2Morelet(3)3,PC1PC23060d,3060dPC2,PC119961119976305PC1PC248dMJO(a.PC1PC2,b.MJOA,B,CDPC1()PC2()()PC1PC2,(:))Fig.5SampleofrunningcorrelationbetweenPC1andPC2andtheMJOcategoriesclassificationbasedona48dayscycleofMJO(a.RunningcorrelationbetweenPC1andPC2,b.MJOcategoryA,B,C,andDcorrespondingtothephaseof(thicksolidline;scaleonright2handaxis)ofZwiththephaseofPC1(dashedline)andPC2(dot2dashedline);scaleontheleft2handaxis)541:/©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.60d,4EOF1EOF2OLROLR5S5N2,,OLRMJOEOFOLR,EOFMJO,,MJO2MJO,,,3060d,MJOPC1PC2(5a),PC1PC212d,,1/4MJO12d,PC1PC290MJO48d,PC1PC2036048dMJO,MJO4,A,B,CD,12d,PC1PC290(5b)A=0,PC10,PC2,B=90,PC1,PC20,CD57d,MJO,MJOTD/TC,MJO,715d4MJOTD/TC19969199763060dEOF,MJOA,B,C,DOLR(6),OLRADMJOA,,,OLRMJO;B,,(SPCZ),MJO;C,MJO,D,,,ADOLRMJOTD/TCMJO,,MJOABTD/TC,BCTD/TC,CDTD/TC71996919976MJOA,B,CDTD/TC,A,TD/TC,TD/TCB,TD/TCCTD/TC,TD/TC,TD/TCD,TD/TC,TD/TCAD,TD/TCMJO(6),MJO,TD/TCMJO1MJOA,B,CDTD/TC,5TD/TC,80%(20%)TD/TCMJO(),MJOTD/TC6462©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.61996919976MJOA,B,CDOLR(5W/m2,)Fig.6OLRanomalies,regressedbyfirsttwoleadingEOFmodesineveryMJOcategoryof(a)A,(b)B,(c)C,and(d)D.(Thecontourintervalis5W/m2;thezerocontoursareomitted,andthenegativecontoursareshaded)18TD/TC61%(22%)MJO(),TD/TCMJO,17%,MJOTD/TC60%30TD25TC,47%(40%)TD(TC)MJO,23%(28%)TD(TC)MJO,30%(32%)TD(TC)MJO18TD/TC,67%(27%)TD/TCMJO(),MJOTD/TC6%,,TD/TCMJO,,MJOTD/TCTD/TC741:/©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.71996919976TD()TC()MJOA,B,CDFig.7PositionofTD(opencircle)andTC(cross)ineachMJOcategoryof(a)A,(b)B,(c)C,and(d)D,duringtheperiodofSeptember1996toJune199711996919976TD/TCMJOA,B,CD(TCTD/TC(JTWC))Table1Percentageoftropicaldepression(TD)andcyclone(TC)occurredintheIndiantowesternPacificOceansduringtheperiodofSeptember1996toJune1997,correspondingtothecategoryofMJOA,B,C,D,andwestwardpropagatingphase.DatasetisfromtheJointTyphoonWarmingCenter(JTWC)MJO(%)(%)(%)(%)A60(20)33(33)10(20)6(6)B20(60)28(28)20(4)16(22)C20(20)5(5)27(36)33(28)D0(0)17(17)13(8)39(38)MJO0(0)17(17)30(32)6(6)8462©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.MJO,MJO5EOF,MJO1996919976/MJO,,/MJOMJO,/,/MJOMJO/,/MJO,MJO/,/,:YuhjiKurodaEOF,Morelet:7027082MaddenRA,JulianPR.Observationsofthe4050daytropicaloscillation:Areview.MonWeaRev,1994,122:8148373..,1990,14(1):32454YasunariT.CloudinessfluctuationsassociatedwiththeNorthernHemispheremonsoon.JMeteorSocJapan,1979,58:2252295HendonHH,LiebmannB.AcompositestudyofonsetoftheAustraliansummermonsoon.JAtmosSci,1990,47:222722406HendonHH,LiebmannB.Theintraseasonal(3050day)oscillationoftheAustraliansummermonsoon.JAtmosSci,1990,47:290929237WeickmannKM.IntraseasonalcirculationandoutgoinglongwaveradiationmodesduringNorthernHemispherewinter.MonWeaRev,1983,111:183818588LauKM,PhillipsTJ.Coherentfluctuationsofextratropicalgeopotentialheightandtropicalconvectioninintraseasonaltimescales.JAtmosSci,1986,43:116411819FerrantiL,Palmer