简介：ElNioorLaNiamanifestinDecemberoverthePacificandwillserveasanindexfortheforecastingofsubsequentIndiansummermonsoon,whichoccursfromJunetomid-September.Inthepresentarticle,anattemptismadetostudythevariationoflatentheatflux(LHF)overthenorthIndianOceanduringstrongElNioandstrongLaNiaandrelateitwithIndianmonsoonrainfall.DuringstrongElNiotheLHFintensityishigherandassociatedwithhigherwindspeedandlowercloudamount.DuringElNioallIndiarainfallishavinganinverserelationwithLHF.SeasonalrainfallishigherinYY+1(subsequentyear)thanYY(yearofoccurrence).HoweverthereisalaginrainfallduringElNioYY+1fromJunetoJulywhencomparedwiththemonthlyrainfall.

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简介：ThetropicalPacifichasbeguntoexperienceanewtypeofElNio,whichhasoccurredparticularlyfrequentlyduringthelastdecade,referredtoasthecentralPacific(CP)ElNio.Variouscoupledmodelswithdifferentdegreesofcomplexityhavebeenusedtomakereal-timeElNiopredictions,buthighuncertaintystillexistsintheirforecasts.ItremainsunknownastohowmuchofthisuncertaintyisspecificallyrelatedtothenewCP-typeElNioandhowmuchiscommontoboththistypeandtheconventionalEasternPacific(EP)-typeElNio.Inthisstudy,thedeterministicperformanceofanElNio–SouthernOscillation(ENSO)ensemblepredictionsystemisexaminedforthetwotypesofElNio.EnsemblehindcastsarerunforthenineEPElNioeventsandtwelveCPElNioeventsthathaveoccurredsince1950.Theresultsshowthat(1)theskillscoresfortheEPeventsaresignificantlybetterthanthosefortheCPevents,atallleadtimes;(2)thesystematicforecastbiasescomemostlyfromthepredictionoftheCPevents;and(3)thesystematicerrorischaracterizedbyanoverlywarmeasternPacificduringthespringseason,indicatingastrongerspringpredictionbarrierfortheCPElNio.Furtherimprovementstocoupledatmosphere–oceanmodelsintermsofCPElNiopredictionshouldberecognizedasakeyandhigh-prioritytaskfortheclimatepredictioncommunity.

简介：AftercompositingthreerepresentativeENSOindices,ElNioeventshavebeendividedintoaneasternpattern(EP)andacentralpattern(CP).ByusingEOF,correlationandcompositeanalysis,therelationshipandpossiblemechanismsbetweenIndianOceanDipole(IOD)andtwotypesofElNiowereinvestigated.IODevents,originatingfromIndo-Pacificscaleair-seainteraction,arecomposedoftwomodes,whichareassociatedwithEPandCPElNiorespectively.TheIODmoderelatedtoEPElNioevents(namedasIOD1)isstrongestatthedepthof50to150malongtheequatorialIndianOcean.Besides,itshowsaquasi-symmetricdistribution,strongerinthesouthoftheEquator.TheIODmodeassociatedwithCPElNio(namedasIOD2)hasstrongestsignalintropicalsouthernIndianOceansurface.Intermsofmechanisms,beforeEPElNiopeaks,anomalousWalkercirculationproducesstronganomalouseasterliesinequatorialIndianOcean,resultinginupwellingintheeast,decreasingseatemperaturethere;acoupleofanomalousanticyclones(strongerinthesouth)formofftheEquatorwherewarmwateraccumulates,andthustheIOD1occurs.WhenCPElNiodevelops,anomalousWalkercirculationisweakerandshiftsitscentertothewest,thereforeanomalouseasterliesinequatorialIndianOceanislessstrong.Besides,theanticyclonesouthofSumatrastrengthens,andthesoutherlieseastofitbringcoldwaterfromhigherlatitudesandnortherlieswestofitbringwarmwaterfromlowerlatitudestothe15°to25°Szone.Meanwhile,thereexistsstrongdivergenceintheeastandconvergenceinthewestpartoftropicalsouthernIndianOcean,makingseatemperaturefallandriseseparately.Therefore,IOD2liesfarthersouth.

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简介：利用1964-1993年NCEP／NCAR再分析风应力资料和中国科学院大气物理研究所发展的14层热带太平洋环流模式（OGCM），对热带太平洋与E1Nin^~o有关的年际变化进行了研究。首先，分析了西太平洋暖池次表层海温异常（SOTA）与Nin^~o3区海表温度异常（SSTA）的年际变化关系，发现在E1Nin^~o事件之前，暖池的次表层海温都有明显正异常出现，它的东传导致了E1Nin^~o的发生，并且SOTA的传播随纬度变化，沿赤道东传，在赤道外西传。然后，选取了20世纪70年代和80年代两次最强的E1Nin^~o事件讨论了引起这种机制的可能原因——西风异常的作用。最后，对1964-1993所有的E1Nin^~o年的风场、次表层海温和海表温度的异常进行了综合分析。

简介：Fivesetsofmodelsensitivityexperimentsareconductedtoinvestigatetheinfluenceoftropicalcyclone(TC)genesislocationandatmosphericcirculationoninterannualvariabilityofTCintensityinthewesternNorthPacific(WNP).Ineachexperiment,bogusTCsareplacedatdifferentinitiallocations,andsimulationsareconductedwithidenticalinitialandboundaryconditions.Inthefirstthreeexperiments,thespecifiedatmosphericandSSTconditionsrepresentthemeanconditionsofElNio,LaNia,andneutralyears.TheothertwoexperimentsareconductedwiththespecifiedatmosphericconditionsofElNioandLaNiayearsbutwithSSTsexchanged.ThemodelresultssuggestthatTCsgeneratedinthesoutheasternWNPincurredmorefavorableenvironmentalconditionsfordevelopmentthanTCsgeneratedelsewhere.ThedifferentTCintensitiesbetweenElNioandLaNiayearsarecausedbydifferenceinTCgenesislocationandlow-levelvorticity(VOR).VORplaysasignificantroleintheintensitiesofTCswiththesamegenesislocationsbetweenElNioandLaNiayears.

简介：近年铝合金窗户在高层建筑中得到广泛应用。本文围绕铝合金窗户的防雷接地的施工和检测进行了总结，为今后铝合金窗户的防雷检测工作提供参考。