简介：由与曾经历史上发生了的ENSO事件作比较，基本特征和热带太平洋的异常海面温度的可能的原因特征地在1997和1998期间被分析了。1997/1998ElNino有重要畸形和怪癖，这被发现。掉进“简单东方模式”或“西方的模式”不同于以前的ElNino事件。1997/1998ElNifio事件的预言也与一口中间的海洋空气被测试了联合动态模型。结果证明24铅月为温暖的事件预报的0~的技巧都超过0.5。成熟阶段的预言和温暖的事件的以后的阶段比开始的阶段的那些好。

简介：Basedonthedailyprecipitationandtemperaturedataof97stationsinSouthwestChina(SWChina)from1960to2009,adry-wetindexiscalculated.Thespatiotemporalvariationcharacteristicsofdry-wetconditions,precipitationandtemperaturearestudied.Thentheabnormalatmosphericcirculationcharacteristicsarediscussedusingreanalysisdata.TheresultsshowthatSWChinahasexhibitedanoveralltrendofautumnaldroughtsincethelate1980s,andthisdroughttrendbecamemoresignificantearlyinthe2000s,especiallyintheeasternSWChina.Autumnaldry-wetvariationinsouthwesternChinashowedtwomajormodes:consistentchangeacrosstheentireregionandopposingchangesintheeasternandwesternregions.Thespatialdistributionofdry-wetanomalieswasmoresignificantlyaffectedbyprecipitation,whiletemporalvariationindry-wetconditionswasmorestronglyinfluencedbytemperature.TheformermodeisaffectedbytheanomaliesoftheprecedentSSTneartheWesternPacificWarmPool,theWesternPacificSubtropicalHigh,theEastAsianTroughandtheSouthTrough.ThelattermodeisrelatedtothewindanomaliesintheeasternSWChinaandtheverticalmovementinthewesternandeasternSWChina.Thesearethemaininfluencingfactorsfortheautumndry-wetvariationinSWChina,whichareofgreatsignificancetothepredictionofdrought.

简介：根据强壮的ENSO处理的1982/1983的比较，象快速的开发，巨大的紧张和突然的撤退那样的关键特征在1997/1998关于温暖的事件被揭示，为这个过程在它海洋和空气的发作和进化期间为热带印度洋和西方的太平洋管理intraseasonal摆动的特征特征地详细被学习。

简介：Inthispaper,timeandspacedistributionregularityofmeso-scaleheavyrainsinfiveselectedtyphoonswhichlandedatFujianfrom1996to1998hasbeenanalyzed.Besides,withhourlydigitizedsatelliteinfraredimagery,thefeaturesofthemesoscalearerevealedforthegenesisandevolutionofmesoscaleconvectivesystemsintyphoons.Itindicatesthattheintensityofmesoscalestormsiscloselyconnectedwiththetemperatureandtheareaofthecoldestcloudcluster.Theheavyrainfallusuallyemergesontheeasternsideofthemesoscaleconvectivecloudclusters,wherethecloudmassisdevelopingandwithadensegradientandbigcurvatureofisolineofthecloudtoptemperature.

简介：Basedonintensiveautomaticweatherstationdata,satellitecloudimagery,NCEPreanalyzeddata,andthesimulationresultsfrommesoscalenumericalmodels,thisstudyanalyzesthecharacteristicsandformationmechanismsofthemesoscaleconvectionsystem(MCS)duringtheextremeprecipitationeventthatwastriggeredbyaweakenedlow-pressureinvertedtroughofTyphoonHaikuionAugust10/2012.Theresultsofthisstudyshowthatcoldairattherearofanortheasterncoldvortexcreatesthermodynamicconditionsfavorabletothedevelopmentofextremeprecipitation.Themainbodyofthecoldairisnorthwardlocatedsothatthecoldairinvadesonlythemiddlelayeroftheperipheryoftheinvertedtrough.Thus,thecoldairminimallyaffectsthelowerlayer,whichresultsinaverticallydistributedstructureofthetemperatureadvectionthataugmentstheformationanddevelopmentofconvectiveinstabilitystratification.Inthemiddletroposphere,thecoldairencounterstheconvergent,ascending,warmmoistairfromthelow-pressureinvertedtrough,leadingtofrontogenesis.Thefrontogenesisenhanceswindconvergencewhich,inturn,furtherenhancesthefrontogenesis,andthepositivefeedbackbetweenthesetwoforcesaugmentsthedevelopmentofmeso-andsmall-scaleconvectionsystemsintherainstormregionanditsvicinity,whichstrengthenstheupwardtransportationofwatervaporfromlowlayersandthickeningofwatervaporconvergenceandresultsinlocalheavyrains.

简介：FourobservedblockinganticyclonesindifferentregionsoftheNorthernHemispherearein-vestigated.Analysesshowthatthereexistdistinctdifferencesinthemaintenanceofthetime-meanquasi-geostrophicpotentialvorticity(PV)lowin300hPawithinblockingareas.IntwoPacificblockingcases,thePVadvectionbytime-meanflowtendstoflowthePVlowtonorthwesternpartoftheblockinghighs,andthusisbeneficialtothemaintenanceoftheblockings’strength.Thetransferbytransienteddiesactstobalancetheeffectofthetime-meanflow.IntheAtlanticandAlaskablockingcases,however,theadvectionofmeanflowtendstoflowthePVloweastward.ThePVtransferbytransienteddiesactstoflowpotentialvorticitylowtothewesternpartoftheblockingridgesandalsotobalancethetime-meanflow’seffect.Thus,inthelattertwocases,itisthetransferbythetransienteddiesthatactstomaintaintheblockings.

简介：用观察数据Nanling山并且数字建模向南在区域收集了的合成领域，稠密的雾和可见性，雾落下光谱和雾形成的physicalconcept的季节的特征被分析了。低可见性(200m)的发生频率与24.7%的一个平均数很高，从到冬季和下个弹簧的秋天的目的41.8%的最大值。在春天和冬季Nanling山向南发生在区域的雾进程源于复杂微物理的进程，本地地面，水蒸汽交通和影响天气系统的相互作用。雾过程从移流被产生或上风倾斜，它与放射雾不同。由于本地山提起的空气使冷凝作用凉下来在雾形成起一个重要作用。上风山的斜坡对雾形成有利。稠密的雾能发生在更低的高度在上风山的斜坡，导致更低的可见性。雾比城市的雾的主要具有有更小的数字密度的小落下的光谱，并且它的落下光谱让在更小的直径的节下趋势。在雾水内容和可见性之间的反的关系是在几种关系之中的最好微变量。除了雾身体本身的微物理的进程，当雾身体被风正在搬运时的在山腰上的不规则的爬并且交叉的运动也是为象雾水内容那样的微物理的参数的变化的重要原因。

简介：Basedonthetropicalcyclone(TC)observationsinthewesternNorthPacificfrom2000to2008,thispaperadoptstheparticleswarmoptimization(PSO)algorithmofevolutionarycomputationtooptimizeonecomprehensiveclassificationrule,andapplytheoptimizedclassificationruletotheforecastingofTCintensitychange.Intheprocessoftheoptimization,thestrategyofhierarchicalpruninghasbeenadoptedinthePSOalgorithmtonarrowthesearcharea,andthustoenhancethelocalsearchability,i.e.hierarchicalPSOalgorithm.TheTCintensityclassificationruleinvolvescoreattributesincluding12-HMWS,MPI,andRainratewhichplayvitalrolesinTCintensitychange.ThetestingaccuracyusingthenewminedrulebyhierarchicalPSOalgorithmreaches89.6%.ThecurrentstudyshowsthatthenovelclassificationmethodforTCintensitychangeanalysisbasedonhierarchicPSOalgorithmisnotonlyeasytoexplainthesourceofrulecoreattributes,butalsohasgreatpotentialtoimprovetheforecastingofTCintensitychange.

简介：Datacollectedusingthemicrorainradar(MRR)situatedinJinancity,easternChina,wereusedtoexplorethealtitudinalandtemporalevolutionofrainfallmicrophysicalcharacteristics,andtoanalyzethebrightband(BB)characteristicsandhydrometeorclassification.Specifically,alow-intensityandstablestratiformprecipitationeventthatoccurredfrom0000to0550UTC15February2015andfeaturedaBBwasstudied.Duringthisevent,therainfallintensitywaslessthan2mmh-1ataheightof300m,whichwasabovetheradarsitelevel,sotheerrorscausedbytheverticalairmotioncouldbeignored.ThefreezingheightfromtheradiosondematchedwellwiththetopoftheBBobservedbytheMRR.Itwasalsofoundthatthenumberof0.5–1mmdiameterdropsshowednonoticeablevariationbelowtheBB.Themaximumfallvelocityandthemaximumgradientfallvelocity(GFV)oftheraindropsappearedatthebottomoftheBB.Meanwhile,amethodthatusestheGFVandreflectivitytoidentifythealtitudeandthethicknessoftheBBwasestablished,withwhichtheMRRcanprovideareliableandreal-timeestimationofthe0?Cisotherm.ThedropletfallvelocitywasusedtoclassifythetypesofsnowcrystalsabovetheBB.Inthefirst20minoftheselectedprecipitationevent,graupelprevailedabovetheBB;andatanaltitudeof2000m,graupelalsodominatedinthefirst250min.After150min,theexistenceofgraupelanddendriticcrystalswithwaterdropletsabovetheBBwasinferred.

简介：Fifty-eightextratropicaltransition(ET)casesintheyears2000-2008,including2,021observations(at6-hourintervals),overthewesternNorthPacificareanalyzedusingthecyclonephasespace(CPS)method,inanefforttogetthecharacteristicsofthestructureevolutionandenvironmentalconditionsoftropicalcyclones(TCs)duringEToverthisarea.ClusteranalysisoftheCPSdatasetshowsthatstrongTCsaremorelikelytoundergoET.ETbeginswiththeincrementofthermalasymmetryinTCs,alongwiththegenerationandintensificationofanupper-levelcoldcore,andendswiththeoccurrenceofalower-levelcoldcore.ETlastsanaveragedurationofabout28hours.Dynamiccompositeanalysisoftheenvironmentalfieldofdifferentclustersshowsthat,ingeneral,whenTCsmovenorthward,theyaregraduallyembeddedinthewesterliesandgraduallytransformintoextratropicalcyclonesundertheinfluenceofthemid-andhigher-latitudebaroclinicsystems.AsforthoseTCswhichcompleteET,thereisalwaysmuchgreaterpotentialvorticitygradientinthenorthwestofthemandobviouswatervaportransportchannelsintheenvironment.

简介：Using1°×1°finalanalysis(FNL)datafromtheNationalCentersforEnvironmentalPrediction(NCEP),precipitationdatafromtheTropicalRainfallMeasuringMission(TRMM)andthebest-tracktropicalcyclone(TC)datasetprovidedbytheJapanMeteorologicalAgency(JMA)forJune-Augustof2000-2009,wecomprehensivelyconsiderthetwofactorslow-levelmoisturechannelandinteractionbetweenTCsandmid-latitudesystemsandimplementastatisticalanalysisofremoteprecipitationinEastAsiatothenorthof0°andtothewestof150°E.48casesofremoteprecipitationoccurredinthisperiod,whicharecategorizedintofiveclasses.Afteracompositeanalysisofthedifferentclasses,themainsystemsat850hPaand500hPathatimpacttheremoteprecipitationareasfollows:TC,mid-latitudetrough,subtropicalhighandwatervaporchannel.Inparticular,thewatervaporchannelwhichusuallyconnectswithIndianmonsoonhasthemostsignificantimpactonremoteheavyrainfall.Anotherimportantfactoristhemid-latitudetrough.Thetypeofnorthtrough/vortex-southTCremoteprecipitationeventshappenmostfrequently,accountingfor68.8%ofthetotalincidence.MostremoteprecipitationeventsoccurontherightsideoftheTCpath(representing71%ofthetotalnumber).At200hPa,theremoteprecipitationeventsusuallyoccurontherightrearportionofahigh-altitudejetstream,andthereisananti-cyclonicvortextotheeastandwestoftheTCs.Whenthereisnoanti-cyclonicvortextotheeastoftheTC,theTCisrelativelyweak.WhentheremoteprecipitationoccurstothenorthwestoftheTCandthereisatroughinthenorthwestdirection,theTCisrelativelystrong.NumericalexperimentsarecarriedoutusingWeatherResearchandForecast(WRF)model.TheresultsshowsthattheTCplaysamainroleinproducingtheheavyprecipitationandresultsintheenhancementofprecipitationbyimpactingthewatervaporchannel.

简介：Thispaperpresentsahigh-resolutionsimulationofaremarkablepolarlowobservedovertheSeaofJapanon21January1997byusinga5-kmmeshnon-hydrostaticmodelMRI-NHM(MeteorologicalResearchInstituteNon-HydrostaticModel).A24-hoursimulationstartingfrom0000UTC21January1997successfullyreproducedtheobservedfeaturesofthepolarlowsuchasthewrappingofwesternpartofaninitialEWorientationvortex,thespiral-shapedbands,thecloud-free'eye',andthewarmcorestructureatitsmaturestage.The'eye'ofthesimulatedpolarlowwasrelativelydry,andwasassociatedwithastrongdowndraft.Athermodynamicbudgetanalysisindicatesthatthe'warmcore'inthe'eye'regionwasmainlycausedbytheadiabaticwarmingassociatedwiththedowndraft.Therelationshipamongthecondensationaldiabaticheating,theverticalvelocity,theconvergenceofthemoistureflux,andthecirculationaveragedwithina50km×50kmsquareareaaroundthepolarlowcentershowsthattheyformapositivefeedbackloop,andthisloopisnotinconsistentwiththeCISK(ConditionalInstabilityoftheSecondKind)mechanismduringthedevelopingstageofthepolarlow.

简介：ThestatisticalcharacterofQuikSCATscatterometerwindsisshowed.AndMonthlychangeandspecialdistributioncharacterofstrongwindfrequencyandmonthlywindfieldsinSouthChinaSeaisanalyzed.ItisshownintheresultthattheQuikSCATscatterometerwindscanberelieduponfortheSouthChinaSea;twowinds,onethewintertimenortheasterlyandtheothersummertimesouthwesterly.ThenortheasterlycentersattheBashiStraitandTaiwamStraitanditssecondarycenterandthemaximumcenterofthesouthwesterlyareinthecentralandsouthernSouthChinaSea.

简介：AssimilatingsatelliteradiancesintoNumericalWeatherPrediction(NWP)modelshasbecomeanimportantapproachtoincreasetheaccuracyofnumericalweatherforecasting.Inthisstudy,theassimilationtechniqueschemewasemployedinNOAA’sSTMAS(Space-TimeMultiscaleAnalysisSystem)toassimilateAMSU-Aradiancesdata.Channelselectionsensitivityexperimentswereconductedonassimilatedsatellitedatainthefirstplace.Then,realcaseanalysisofAMSU-Adataassimilationwasperformed.Theanalysisresultsshowedthat,followingassimilatingofAMSU-Achannels5-11inSTMAS,theobjectivefunctionquicklyconverged,andthechannelverticalresponsewasconsistentwiththeAMSU-Aweightingfunctiondistribution,whichsuggeststhatthechannelscanbeusedintheassimilationofsatellitedatainSTMAS.WiththecaseoftheTyphoonMorakotinTaiwanIslandinAugust2009asanexample,experimentsonassimilatedandunassimilatedAMSU-AradiancesdataweredesignedtoanalyzetheimpactoftheassimilationofsatellitedataonSTMAS.TheresultsdemonstratedthatassimilationofAMSU-Adataprovidedmoreaccuratepredictionoftheprecipitationregionandintensity,andespecially,itimprovedthe0-6hprecipitationforecastsignificantly.

简介：TheNCEP/NCARIIdailymeanreanalysisdataandobservedprecipitationdataareemployedtoinvestigatethewestwardextensionofthewesternPacificsubtropicalhigh(WPSH)duringtheheavyrainperiodoverthesouthernChinainJune2005.Resultsshowthattheremayexistarelationshipbetweentheeast-westshiftoftheWPSHandtheprocessofasouthernChinaheavyrain.TheanalysisindicatesthattheverticalmotionintheWPSHareaismainlycausedbythelatentheatreleaseofmonsoonrainbeltsonitsnorthernandsouthernsides.TheverticalmotioncouldcausetheaccumulationofairmassinthecenterandwestoftheWPSH,whichleadstoitsstrengthening.TheappearanceofthenorthernandsouthernmonsoonrainbeltscouldnotonlyenhancetheWPSHbystrengtheningthedescendingdraft,butalsoexcitethedevelopmentofpositivevorticityandrestricttheWPSH'smovementinthenorth-southdirection.Moreover,theIndianmonsoonrainfalltothewestoftheWPSHmayexcitethedevelopmentofanticyclonicvorticityonitseasternside,whichleadstothewestwardextensionoftheWPSH.

简介：TheonsetofSouthChinaSeasummermonsoonin1998occurredonMay21st.UsingtheU.S.NationalCentersforEnvironmentalPredictionreanalysisdata,thispaperexaminesthephysicalprocessoftheweakeningofasubtropicalanticycloneinWestPacificduringtheonsetperiodusingtheZwack-Okossivorticityequation.Resultsshowthatduringthepre-onsetperiod,thepositivevorticityadvectioninfrontofanuppertropospherictroughwasthemostdominantphysicalmechanismfortheincreaseofthecyclonicvorticityonthe850-hPalayerovertheSouthChinaSeaanditsnearbyregion.Thesecondarycontributiontotheincreaseofthecyclonicvorticitywasthewarm-airadvection.Aftertheonset,themagnitudeofthelatent-heatwarmingtermrapidlyincreasedanditseffectontheincreaseofthecyclonicvorticitywasaboutthesameasthepositive-vorticityadvection.Theadiabatictermanddivergencetermcontributednegativelytotheincreaseofthecyclonicvorticitymostofthetime.Thus,thepositivevorticityadvectionisthemostimportantphysicalmechanismfortheweakeningoftheWestPacificsubtropicalanticycloneovertheSouthChinaSeaduringtheonsetperiod.

简介：mesoscale表面气象站的观察数据和广东省的天气雷达被采用分析传送对流的不对称的分发在以前，在期间并且在以后乍见陆地为在2006.The结果在华南海岸上乍见陆地做的Chanchu和Prapiroon的热带气旋证明那强壮的传送对流位于landfallingChanchu和Prapiroon的东方、北的部门，也就是在前面和TC的正确部分追踪，为时间starti的一个时期他们的传送对流也在垂直方向有不同差别。尽管，分析显示了那乍见陆地Chanchu和Prapiroon有传送对流的一样的不对称的分发，原因不是一模一样的。在Chanchu的情况中的传送对流的不对称的分发主要与大环境垂直的风的影响被相关砍，低级的水平风砍，并且低级集中和分叉。然而，在Prapiroon的情况中，传送对流的不对称的分发主要与低级集中和分叉的影响被联系。

简介：Basedonthedata(includingradiusofmaximumwinds)fromtheJTWC(JointTyphoonWarningCenter),thetropicalcyclones(TCs)radiioftheoutermostclosedisobar,TCsbesttracksfromShanghaiTyphoonInstituteandtheBlackBodyTemperature(TBB)oftheJapanesegeostationarymeteorologicalsatelliteM1TRIR1,andcombining13tropicalcycloneswhichlandedinChinaagainaftervisitingtheislandofTaiwanduringtheperiodfrom2001to2010,weanalyzedtherelationshipbetweenthenumberofconvectivecoreswithinTCcirculationandtheintensityofTCwiththemethodofconvective-stratiformtechnique(CST)andstatisticalandcompositeanalysis.Theresultsareshownasfollows:(1)ThenumberofconvectivecoresintheentireTCcirculationiswellcorrespondingwiththeouterspiralrainbandsandthedensityofconvectivecoresintheinnercoreareaincreases(decreases)generallywithincreasing(decreasing)TCintensity.Atthesametime,thenumberofconvectivecoreswithintheouterspiralrainbandsismorethanthatwithintheinnercoreanddoesnotchangemuchwiththeTCintensity.However,thedensityofconvectivecoreswithintheouterspiralrainbandsislowerthanthatwithintheinnercore.(2)TherelationshipdescribedaboveissensitivetolandinglocationtosomeextentbutnotsensitivetothestructureofTC.(3)TheaveragevalueofTBBintheinnercoreareaincreases(decreases)generallywithincreasing(decreasing)ofTCintensity,whichisalsosensitivetolandingsituationtosomeextent.Atthesametime,theaveragevalueofTBBwithintheouterspiralrainbandsisclosetothatwithintheentireTCcirculation,andbothofthemaremorethanthatwithintheinnercore.However,theydonotreflectTCintensitychangesignificantly.(4)TheresultsofstatisticalcompositebasedonconvectivecoresandTBBarecomplementarywitheachother,soacombinationofbothcanreflecttherelationshipbetweenTCrainbandsandTCintensitymuchbetter.

简介：一四维变化(4D-Var)数据吸收方法在热带太平洋的一个改进中间的联合模型(ICM)被实现。一个成双的实验被设计基于ICM在ENSO分析和预言上评估4D-Var数据吸收算法的影响。模型错误被假定仅仅从参数无常产生。SST异例的观察，从拿缺省参数价值并且把Gaussian噪音增加的真相模型模拟被取样，直接错误地与它的参数集合被吸收进吸收模型。结果证明4D-Var有效地减少ENSO分析的错误因此与非吸收盒子相比改进ENSO事件的预言技巧。这些结果提供一个有希望的方法让ICM完成更好即时的ENSO预言。

简介：喷雾器光性质被模仿用光谱为喷雾器种类(SPRINTARS)的放射运输模型结合了非静水力学的ICosahedral大气的模型(NICAM)。3年的全球吝啬的所有天空喷雾器在550nm的光厚度(AOT)，?ngstr?m代表(AE)分别地在0.123，0.657和0.944点基于在440和870nm，和在550nm的单个散布反照率(SSA)的AOT被估计。为每喷雾器种，吝啬的AOT在AeroCom模型的范围以内。建模的所有天空和清楚天空的结果与从中等分辨率成像分光辐射函数(MODIS)和喷雾器机器的网络(AERONET)的观察相比。所有天空AOT的模仿的空间与时间的分布能通常复制MODIS检索，和关联和模型技巧能稍微在大多数陆地区域上用清楚天空的结果被改进。之间的差别清楚天空并且所有天空AOT在弄脏的区域上是更大的。与从AERONET的观察相比，建模并且观察的所有天空AOT和AE通常在合理同意，而SSA变化很好没被捕获。尽管所有天空和清楚天空的结果的空间与时间的分布是类似的，清楚天空的结果更好通常与观察被相关。清楚天空的AOT和SSA比所有天空结果的通常低，特别在喷雾器化学药品作文主要被硫酸盐喷雾器贡献的那些区域。建模的清楚天空的AE比在吸水的喷雾器统治的那些区域上的所有天空AE大，当反面在恐水病的喷雾器统治的区域上被发现时。