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简介：Thermalconvectiveprecipitation(TCP)oftenoccursovermainlandChinainsummerwhentheareaisdominatedbythewesternPacificsubtropicalhigh(WPSH).ItiswellknownthattheWPSHoftenbringsaboutlargescalesubsidence,thenwhycoulddeepmoistconvectionoccurandwheredoesthewatervaporcomefrom?Inthispaper,adeepconvectiveprecipitationcasethathappenedon2August2003isstudiedinordertoaddressthesetwoquestions.First,thecharacteristicsoftheTCPeventareanalyzedusingtheTropicalRainfallMeasuringMission(TRMM)satellitedata,automaticweatherstationobservations,andthedatafromtheUSNationalCentersforEnvironmentalPrediction(NCEP).Second,watervaporsourcesareidentifiedthroughexaminingsurfaceevaporation,watervaporadvection,andwatervaporfluxdivergencecalculatedbyusingaregionallyaveragedwatervaporbudgetequation.Furthermore,usinganAdvancedRegionalEta-coordinateModel(AREM),contributionsofsensibleandlatentheatfluxestotheTCParecomparedthroughfoursensitivityexperiments.TheresultsshowthatintheregionscontrolledbytheWPSH,surfacetemperaturerisesrapidlyaftersunrise.Uponreceivingenoughsensibleheat,theairgoesupandleadstoconvergenceintheloweratmosphere.Thenthewatervaporassembledfromthesurroundingsandthegroundsurfaceistransportedtotheupperlevels,andafavorableenvironmentfortheTCPforms.Amodeldatadiagnosisindicatesthatabouthalfofprecipitablewatercomesfromtheconvergenceofhorizontalfluxesofwatervapor,andtheotherhalffromsurfaceevaporation,whilelittleisfromadvection.AdditionalsensitivityexperimentsprovethatbothsensibleandlatentheatingareessentialfortheonsetoftheTCP.Thesensibleheatfluxtriggersthermodynamicascendingmotion,andthelatentheatfluxprovideswatervapor,butthecontributiontoTCPfromthelatterisalittlesmallerthanthatfromtheformer.

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简介：Ｄｉｓｔｒｉｂｕｔｉｏｎａｌｆｅａｔｕｒｅｓｏｆδ１８ＯｉｎｐｒｅｃｉｐｉｔａｔｉｏｎｉｎＣｈｉｎａＺＨＡＮＧＸｉｎｐｉｎｇＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｇｒａｐｈｙ，ＨｕｎａｎＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｃｈａｎｇｓｈａ４１００８１ＣＨＩＮＡ...

简介：Theprecipitationefficiencyanditsrelationshiptophysicalfactorsareexaminedbyanalyzingatwo-dimensionalcloud-resolvingmodelsimulationduringTOGACOAREinthisstudy.Thebasicphysicalfactorsincludeconvectiveavailablepotentialenergy,water–vaporconvergence,verticalwindshear,cloudratio,seasurfacetemperature,airtemperature,andprecipitablewater.Precipitationefficienciesdonotshowacloserelationshiptoairtemperaturenortoseasurfacetemperaturenortoprecipitablewater.Theprecipitationefficiencyincreasesasthewater–vaporconvergencerateincreasesandverticalwindshearweakens,whereasitdecreasesastheconvectiveavailablepotentialenergydissipatesandanvilcloudsdevelop.

简介：Aquantitativeschemeisputforwardinourworkofforecastingthestormrainfalloftyphoonsforspecificsites.Usingtheinitialparameters,weathersituationsandphysicalquantitiesaswellasnumericalweatherpredictionproducts,theschemeconstructsmultivariate,objectiveandsimilaritycriteriaforenvironmentalfactorsforthetimebetweenthecurrentandforthcomingmomentwithinthedomainofforecast.Throughdefininganon-linearsimilarityindex,thisworkpresentsacomprehensiveassessmentofthesimilaritybetweenhistoricalsamplesoftyphoonsandthosebeingforecastintermsofcontinuousdynamicstatesunderthemultivariatecriteriainordertoidentifysimilarsamples.Thehistoricalrainfallrecordsofthesimilarsamplesareusedtorunweightedsummarizationofthesimilarityindextodeterminesite-specificandquantitativeforecastsoffuturetyphoonrainfall.Samplesresemblingthetyphoonbeingforecastareselectedbydefininganon-linearsimilarityindexcomposedofmultiplecriteria.Trialtestshavedemonstratedthatthisschemehaspositivepredictionskill.

简介：Radiosondeprofilesoftemperatureanddewpointtemperaturefromonestationareusedtoforecast12-hprecipita-tionoverNairobi,Kenya.Theforecastschemeisbasedonstatisticalregressionmodelling.Fourpredictorsarederivedfromdatatouseinaprognosticequationtoget12-hprecipitationforecast.Observedandpredictedrainfallvaluesareplottedonagraphagainsttime.Forecastverificationshowsthattheforecastsarepositivelycorrelatedwithobservations.

简介：从CMORPH(气候预言中心Morphing技术)和TRMM(热带降雨测量使命)的每日的降水数量和频率3B42降水产品在原处对温暖的季节被验证在到它的东方的西藏的高原和这些区域上的从2003～2008的降水观察。结果显示这二卫星数据集能更好比每日的降水数量检测每日的降水频率。CMORPH和TRMM3B42的能力精确地检测每日的降水数量依赖于内在的地面。两数据集在东北西藏的高原，四川盆，和比在西藏的高原的复杂地面上的长江的中间降低活动范围的相对扁平的地面上是更可靠的。两个卫星产品能检测每日的降雨事件的出现；然而，他们的表演在复杂地形学的区域是更坏的，例如西藏的高原。由降水紧张的降水数量的地区性的分布基于雨计量器数据基于TRMM3B42接近那些。由对比，类似的分布实质地基于CMORPH不同。CMORPH过高估计当低估与更轻的降水事件联系的雨的数量时，在长江的中间降低活动范围上与最强烈的降水事件联系的雨的数量。CMORPH低估强烈降水的数量并且在另外的分析区域上过高估计更轻的降水的数量。TRMM3B42在四川盆和长江的中间降低活动范围上低估轻降水的频率。CMORPH在长江的中间降低活动范围上过高估计弱、强烈的降水的频率，并且低估中等、重的降水的频率。CMORPH也过高估计轻降水的频率并且在另外的三个区域上低估强烈降水的频率。TRMM3B42产品比CMORPH产品，累积分发为工作偏向更轻的降水事件的提供每日的降水数量的地区性的gamma分布的更好的描述。

简介：Temporalandspatialevolutioncharacteristicsofthe30-60dayoscillation(intraseasonaloscillation,ISO)ofsummerrainfallinChinaandtheeffectsofEastAsianmonsoonontherainfallISOareanalyzedinthispaper.Resultsshowthattheannualanddecadalvariationsoftheoscillationexistbetween1960and2008,andtheintensityisweakestinthelate1970sandearly1980s.InthetypicalstrongyearsoftherainfallISOobtainedfromempiricalorthogonalfunctions(EOFmode1),ananticycloneisinnorthwesternPacificandacycloneisintheeastofChina.Inthetypicalweakyears,thewindISOismuchweaker.Thelow-frequencyzonalwindandwatervaportransportfromthelowlatitudestomid-latitudesinthetypicalstrongyears,andtheoscillationstrengthofdiabaticheatingismuchstrongerthanthatintheweakyearsoftherainfallISO.TheanomalycharacteristicsoftherainfallISOshowanti-phasesbetweentheYangtzeRiverbasinandsouthofChina.AsforthetypicalstrongyearsoftherainfallISOintheYangtzeRiverbasin(EOFmode2),themainoscillationcenterofwatervaporisintheeastofChina(20-30°N,110-130°E).Inthepeak(break)phaseoftherainfalloscillation,alow-frequencycyclone(anticyclone)isintheYangtzeRiverbasinandananticyclone(cyclone)isnearTaiwanIsland.Inaddition,thepeakrainfallcorrespondstotheheatsourceintheYangtzeRiverbasinandtheheatsinkintheQinghai-TibetPlateau.AsforthetypicalstrongyearsoftherainfallISOinthesouthofChina,themainoscillationcenterofwatervaporissouthof20°N.Inthepeak(break)phaseoftherainfallISO,alow-frequencycyclone(anticyclone)isinthesouthofChinaandananticyclone(cyclone)isinthePhilippines.ThepeakrainfallcorrespondstotheheatsourceinthesouthofChinaandtheSouthChinaSea,andtheheatsinkinthewestofIndochina.

简介：ＭｏｄｅｌｌｉｎｇｔｈｅＩｎｔｅｒａｎｎｕａｌＶａｒｉａｔｉｏｎｏｆＲｅｇｉｏｎａｌＰｒｅｃｉｐｉｔａｔｉｏｎ　ｏｖｅｒ　ＣｈｉｎａＷａｎｇＨｕｉｊｕｍ（王会军）（ＬＡＳＧ，ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒｉｃＰｈｙｓｉｃｓ，ＣｈｉｎｅｓｅＡ...

简介：TheregionalcharacteristicsofprecipitationanomaliesoftotalsummerprecipitationofJune,JulyandAugustandindividualmonthlyprecipitationareanalyzedbyusingthemethodofVarimaxEOFandcorrelationanalysis.Thedatasetusedistheprecipitationofa5°Lat.×5°Long.spatialuniformnetworkoverChinaintheperiodof1959to1994.TheanalysisoftotalsummerprecipitationshowsthatthemostsignificantregionalcharacteristicistheexistenceofnegativecorrelationinprecipitationanomaliesbetweenthelowerreachesoftheChangjiangRiverandtheHuaiheRiverValley(theLRCHregion)andthemiddlereachesoftheHuangheRiverValley(theMRHregion),andbetweentheLRCHregionandSouthChina.TheprecipitationanomalyovertheSichuanBasinisnegativelycorrelatedwiththatovereasternpartofQinghai-XizangPlateauandthatovertheLRCHregion.TheregionalcharacteristicsofsummerprecipitationanomaliesinwesternChinaarethatthereexistsnegativecorrelationbetweenthesummerprecipitationanomaliesoverthesouthernpartofthecentralandeasternQinghai-XizangPlateauandthatoveritsnorthernpart.TherealsoexistspositivecorrelationbetweenthesouthernpartofthecentralandeasternQinghai-XizangPlateauandtheeasternpartofNorthChinaandthesouthernpartofNortheastChina.Theabovespatialcorrelationmodeshavesignificantperiodsofabout3yearsandtenyears.TheanalysisofthemonthlyprecipitationshowsthatinJunethereexistspositivecorrelationamongtheprecipitationanomaliesovertheLRCHregion,theeasternpartofNorthChinaandNortheastChina.InJuly,theprecipitationsintheMRHregionandtheLRCHregionarenegativelycorrelated.TheregionalcharacteristicofprecipitationanomaliesinAugustisverysimilartothatofthetotalsummerprecipitationanomalies.

简介：PrecipitationstudywascarriedoutinNi-35at.pctCralloybymeasuringelectricalresistivityatdifferentageingtemperaturesandlongageingtimes.Duringageing,itwasobservedthatelectricalresistivityinitiallyrosewithageingtimeandthenfellafterverylongageingataconstanttemperature.TheinitialincreaseinresistivityduringageingmaybeattributedtotheformationofGPzones/Cr-richprecipitatesatearlystagesbynucleationprocessanddecreaseinresistivity,andafterattainingamaximum,isduetothegrowthofprecipitateparticlesandsubsequentlybycoarseningoftheseprecipitates.TheresultsofelectricalresistivitymeasurementsduringageingwereconfirmedbyX-raydiffractionanalysisindicatingtheformationofaCr-richphaseandaCr3Ni2phaseintheNimatrix.

简介：2004台风Aere的降水的结构的特征从测量国家航空学空间管理(NASA)的使命(TRMM)的热带降雨用高分辨率的数据被分析。台风的特征在它的发展的不同阶段变化，这被发现。分析降水分发的不对称的引起，从环境预言(NCEP)分析的国家中心的数据被用来计算水蒸汽流动向量的垂直积分。因为这个过程，结果显示出那，与成双台风的循环的唯一的现象一起，在东方台风的北方面的空气电流和它的南部的方面的西南的空气水流在搬运水起一个联合作用蒸汽。而且，它的运输效果在开发的不同阶段极大地变化，显示出为这台风进程的水来源的怪癖。由重降水和水蒸汽流动的一个最大值的区域描绘区域的台风传送对流的分布，以及在台风的发展的不同阶段的强壮的上升运动区域不同。水蒸汽流动和垂直运动的不一致的分发引起台风降水的不均匀的分发。

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简介：ThispaperexplorestheapplicationofArtificialIntelligent(AI)techniquesforclimateforecast.ItpresentsastudyonmodellingthemonsoonprecipitationforecastbymeansofArtificialNeuralNetworks(ANNs).UsingthehistoricaldataofthetotalamountofsummerrainfallovertheDeltaAreaofYangtzeRiverinChina,threeANNsmodelshavebeendevelopedtoforecastthemonsoonprecipitationinthecorrespondingareaoneyear,five-year,andten-yearforwardrespectively.Performancesofthemodelshavebeenvalidatedusinga＇new＇datasetthathasnotbeenexposedtothemodelsduringtheprocessesofmodeldevelopmentandtest.Theexperimentresultsarepromising,indicatingthattheproposedANNsmodelshavegoodqualityintermsoftheaccuracy,stabilityandgeneralisationability.

简介：Thispaperanalyzesthepossibilitytodiscriminatebetweenconvectiveprecipitationandstratiformprecipitation.Thisstudyaimstoimprovethemeasurementofrainfallfromteledetectiondataobtainedbothonthegroundandinspace.Forthis,twoparameters,fractaldimensionandfractallacunarity,areconsidered.Tocalculatethefractaldimension,weusetheapproachofbox-countingandshowthatthefractaldimensiondiffersbetweenconvectivescellsandstratiformsones.Andthenthefractallacunarityparameteriscalculatedbyusingtheslidingboxesalgorithm.Thestudyforalltheregionsshowsthatprecipitationcellscanbedescribedbydifferentlacunaritieswhateverthescaleofanalysis.Wededucethatthetwoparameters,fractaldimensionandfractallacunarity,canbeusedtoclassifyprecipitationsinconvectiveregimeandstratiformregime.

简介：PrecipitationofBaSO4nanoparticleswasstudiedforthefirsttimeinaspeciallydesignedrotatingpackedbed(RPB),whichallowedsamplingatdifferentradialpositionstoprovidebetterinsightofthemechanismofprecipitationinRPB.ParticlesizeandmorphologywerecharacterizedbyTEM,whilethequalityofsynthesizedBaSO4powderswasanalyzedbyXRDandBET,andcomparedwiththosepreparedinastirred-tankreactor.TheimportantroleoftheinletregionoftheRPBinthewholeprecipitationprocesswasexperimentallyconfirmed,asasignificantessenceforthedesignofindustrialRPBfortheprecipitationofsparinglysolublematerials.Theeffectsofdifferentoperatingconditionsonparticlesizewerealsoinvestigated,showingthatparticlesizedecreaseswithincreasingrotationalspeedandliquidflowrate,duetotheenhancementofmicromixingintheRPB.

简介：广州春天降雨主要展出内部年变化30年的ofQuasi每年两次、内部的十的变化，并且在时间放大的弱降雨atinterdecadal的时期。Nino3的SST异例(SSTA)是Guangzhouspring降雨的最强壮的先锋。他们从以前的11月有重要积极关联并且稳定地坚持到4月。在以前的冬季的Nino3SSTA在春天通过NorthPacific副热带的高、低的风影响广州春天降雨。当Nino3SSTA在以前的冬季是积极的时，跳副热带的高度是强烈的，向西，华南位于在搬运到华南的副热带的高度，和水汽的边登上气流的区域被反气旋循环加强到菲律宾的东方。广州春天降雨因此是重的。当Nino3SSTA是否定的时，副热带的高度弱、东方，华南从副热带的高度是遥远的并且位于下气流的区域，并且因为低级气旋的循环控制区域到菲律宾的东方，北方风在华南占优势，搬运到华南的水汽是弱的。广州春天降雨因此是弱的，春天干旱被结果。