简介：何金海，周学鸣，叶荣生ＮｕｍｅｒｉｃａｌＳｔｕｄｙｏｆＵｒａｌＢｌｏｃｋｉｎｇＨｉｇｈ＇ｓＥｆｆｅｃｔＵｐｏｎＡｓｉａｎＳｕｍｍｅｒＭｏｎｓｏｏｎＣｉｒｃｕｌａｔｉｏｎａｎｄＥａｓｔＣｈｉｎａＦｌｏｏｄａｎｄＤｒｏｕｇｈｔ￥ＨｅＪｉｎｈａｉａｎｄＺｈ...

简介：Anewthree-dimensionaldynamicsandelectrificationcoupledmodelhasbeendevelopedforinvestigatingthecharacteristicsofmicrophysics,dynamicsandelectrificationinsidethunderstorms.Thismodelisbasicallymodifiedfromathree-dimensional,time-dependent,anddual-parametercloudmodeloriginallyestablishedinIAP(InstituteofAtmosphericPhysics)andatwo-dimensionalaxisymmetricclouddynamicsandelectrificationcoupledmodel.Primarymodificationstothemodelincludenotonlythecouplingofelectrificationwithdynamicalandmicrophysicalprocesses,butalsothelightningdischargeprocessandscreeninglayereffectatthecloudtopaswell.Apartfromincludingafulltreatmentofsmallionswithattachmenttosixclassesofhydrometeors,theinductiveandnon-inductivechargingmechanismsaremorespecificallyconsidered.AcasesimulationofJuly19.1981CCOPEisperformedaimingtovalidatethepotentialcapabilityofthemodel.Comparisonbetweenmodelresultsandobservationsrevealsthatthemodelhasthecapacitytoreproducemanyoftheobservedcharacteristicsofthunderstormsindynamical,microphysical,andelectricalaspects.

简介：Areviewoften-year’spracticeindevelopingtheimprovedsimultaneousphysicalretrievalmethod(ISPRM)isgiveninthehopethatsomecreativeideascanbedrawnfromit.TheimprovementupontheSPRMisassociatedwiththeunder-determinednessofthisill-posedinverseproblem.Inourexperiment,thepreconditionisobservedthatpriorinformationmustbeindependentofthesatellitemeasurements.Thewell-posedretrievaltheoryhastoldusthattheforwardprocessisfundamentalfortheretrieval,anditisthebridgebetweentheinputofsatelliteradianceandtheoutputofretrievals.Inordertoobtainabetterresultfromtheforwardprocess.thefulladvantageofeverypriorinformationavailablemustbetaken.Itisnecessarytoturntheill-posedinverseproblemintothewell-posedone.ThenbyusingtheRidgeregressionorBayesalgorithmtofindtheoptimalcombinationamongthefirstguess,thetheoreticalanalogueinformationandthesatelliteobservations,theimpactoftheunder-determinednessofthisinverseproblemonthenumericalsolutionisminimized.

简介：Inthispaper,wefirstanalyzedclouddriftwind(CDW)datadistributionintheverticaldirection,andthenreassignedtheheightofeveryCDWintheresearchdomainintermsofbackgroundinformation,andfinally,conductedcontrastnumericalexperimentsofassimilatingtheCDWdatabeforeandafterreassignmenttoexaminetheimpactsontheforecastofthetrackofTyphoonChanthu(1003)from00:00(CoordinatedUniversalTime)21Julyto00:00UTC23July,2010.TheanalysisresultsoftheCDWdataindicatethatthenumberofCDWsismainlydistributedinthemidandupper-troposphereabove500hPa,withthemaximumnumberatabout300hPa.Theheightreassigningmethodmentionedinthisworkmayupdatetheheighteffectively,andtheCDWdataaredistributedreasonablyandnoobviouscontradictionoccursinthehorizontaldirectionafterheightreassignment.Afterassimilatingtheheight-reassignedCDWdata,especiallythewatervaporCDWdata,theinitialwindfieldaroundTyphoonChanthu(1003)becamemorereasonable,andthenthesteeringcurrentleadingthetyphoontomovetothecorrectlocationbecamestronger.Asaresult,thenumericaltrackpredictionsareimproved.

简介：In2005,significantrainfallreinforcementandseveredisasterwasinducedbytropicalcyclone(TC)TalimafteritmadelandfallontheeastofChina.Observationalanalysesshowthatithasrelationshipwithcoldairintrusion.Forinvestigatingtheimpactofcoldairintensity,wemakeuseofWeatherResearchandForecasting(WRF)model,thesynthesizerofNCEP/NCARreanalysisdataandJapanregionalspectralmodeldata,tocarryoutnumericalexperiments.Resultsshowthatrainfallreinforcementoccursinallexperiments.Differentintensityofcoldaircanmodifytherainfalldistributionandintensitysignificantly.Intherainfallcenter,theincrementmaximumofrainfallistwiceaslargeasthatoftheminimum.Moderatecoldairintrusionmayresultinthestrongestrainfallreinforcement.Differentcoldairintensitycanleadtodifferentmotionoflow-levelconvergencelinesandfronts.Thereisagoodrelationshipbetweentherainfallregionandtheeasternpartofthefront.Ononehand,strongcoldairweakenstheTCintensitybyitsintrusionintotheTCcenterandresultsinweakconvergenceandaconvergentzoneandarainbandshiftedsouthward.Ontheotherhand,weakcoldairreducestheconvergenceandmovestheconvergentzoneandrainbandnorthward.Moderatecoldairintrusionmaintainsstronglow-levelconvergenceandhigh-leveldivergence,keepingstrongupwardmotionovercertainregions.Consequently,therainbandbeginstostagnateandrainfallreinforcesabruptlytherein.

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.