简介：Basedoninvestigationof53gapsand25quadrats(15m×15meach)ofnon-gapclosedstandinanold-growthtropicalmontanerainforestofHainanIsland,China,canopydisturbanceregimesandgapregenerationwerestudied.Gapswereellipticalinhorizontalform,theratiooflongaxis/shortaxiswasabout1.4.Percentageofexpandedgaps(EG)andcanopygaps(CG)areainthelandscapewere53.5%and25.2%respectively.EGrangedfrom31.4m2to488.2m2andCG/rom14.9m2to354.2m2,theiraveragesizes...

简介：5月17日晚,由《音乐世界Easy》杂志携手三星Anycall共同打造的"音乐RAIN动·2008大学生音乐节·校园音乐新生力选拔赛"北京站复赛在中央民族大学成功举办。经过唱歌、舞蹈等音乐才艺的现场比拼,最终15组选手成功晋级决赛——音乐梦想,只有一步之遥,谁将最终成为校园音乐新生力偶像,让我们拭目以待!

简介：Usingreal-timedataandtheWRFmesoscalemodel,aheavyraineventintheprocessofMesoscaleConvectiveComplex(MCC)turningintobandedMesoscaleConvectiveSystems(MCSs)during18-19June2010issimulatedandanalyzedinthispaper.Theresultsindicatedthattheformationandmaintenanceofasouthwestvortexandshearlineat850hPawasthemesoscalesystemthataffectedtheproductionofthisheavyrain.Thelow-vortexheavyrainmainlyhappenedinthedevelopmentstageofMCC,andthecircularMCCturnedintobandedMCSsinthelatestagewithmainlyshearlineprecipitation.Inthevicinityofrainfallarea,theintensehorizontalvorticityduetotheverticalshearofuandvcausedtherotation,andincorrespondence,theascendingbranchoftheverticalcirculationtriggeredtheformationofheavyrain.Thedifferentdistributionsofuandvintheverticaldirectionproducedvaryingverticalcirculations.Thehorizontalvorticitynearthelow-vortexandshearlinehadobviousdifferenceswhichledtovaryingreasonsforheavyrainformation.Thelow-vortexheavyrainwasmainlycausedbytheverticalshearofv,andtheshearlinerainfallformedowingtotheverticalshearofbothuandv.Inthisprocess,theverticalshearofvconstitutedtheEW-trendingrainbandalongtheshearline,andthelatitudinalnon-uniformityoftheverticalshearinucausedtheverticalmotion,whichwascloselyrelatedtothegenerationanddevelopmentofMCSsattheshearlineandtheformationofmultiplerainclusters.Therewasalsoasimilardifferenceinthepositively-tiltingterm(conversionfromhorizontalvorticitytoverticalpositivevorticity)neartherainfallcenterbetweenthelow-vortexandtheshearline.Theconversioninthelowvortexwasmainlydeterminedbyбv/бp<0,whilethatoftheshearlinebyбu/бp<0.Thescaleoftheconversionfromthehorizontalvorticitytoverticalvorticitywasrelativelysmall,anditwaseasilyignoredintheaveragedstate.Thetwistingtermwasmainlyconducivetothereinfor

简介：以估计气象学的观察的单个部件的影响(基于地面的GPS能使沉淀的水蒸汽，自动、常规的气象学的观察)在在在北京的2000年7月4-5日的奔流的雨事件上(与24-h积累了到达240公里的降水)，24-h观察系统实验被使用MM5/WRF3DVAR系统和nonhydrostaticMM5模型数字地进行。因为非常规的GPS观察被3DVAR系统，更好起始的领域和24-h模拟直接吸收进起始的分析因为严重降水事件在MM5/Litter_R客观分析计划下面比那些被完成，结果显示那。进一步的分析也证明气象学的观察网络的单个部件在起始的领域分析和预报技巧的改进起他们的特殊积极作用。3DVAR计划与或没有雷送和飞行员观察在数字模拟，和气象学的观察第二评价的自动、常规的表面上有最重要的影响。在从另外的气象学的观察获得补充信息以后，基于地面的GPS能使沉淀的水蒸汽数据能更显然反映起始的地吸收和降水预报。由合并进3DVAR的GPS能使沉淀的水蒸汽数据在起始的时间分析的groundbased，有1，5，10，和20公里的阀值的威胁分数(TS)被l%-8%为6-h增加，24-h分别地积累了降水观察。这个工作给估计存在的单个部件的影响的一个有用例子用3DVAR的高影响天气事件上的气象学的观察网络数字系统。[出版摘要]

简介：Byusingthedatasetoflightraindaysandlowcloudcoverat51stationsinSouthChina(SC),andthemethodoflinearregressionandcorrelativeanalysis,weanalyzethespatiotemporalcharacteristicsofthelightraindaysandlowcloudcoverincludingannualvariationandlong-termseasonalchange.Theresultsareasfollows:(1)ThetrendsoflightraindaysandlowcloudcoveroverSCareopposite(lightraindaystendedtodecreaseandlowcloudcovertendedtoincreaseinthepast46years).Thevaluedistributedineastishigherthanthatinwest,andcoastalareahigherthaninlandarea.(2)Theregressioncoefficientsoflightraindaysandlowcloudcoverduring1960-2005are4.88d/10yearsand1.14%/10yearsrespectively,whichhadallpassedthe0.001significancelevel.(3)Variationsoflightraindaysarerelativelysmallinspringandsummer,buttheircontributionsarelargerforannualvaluethanthatofautumnandwinter.(4)Therearetworegionswithlargevaluesofaerosolopticaldepth(AOD),whichdistributeincentralandsouthernGuangxiandPearlRiverDelta(PRD)ofGuangdong,andthevalueofAODinPRDisupto0.7.Theaerosolindexdistributedincoastalareaishigherthanintheinlandarea,whichissimilartothelightraindaysandlowcloudcoveroverSC.AerosolindexesinSCkeptincreasingwithfluctuationduringthepast27years.TheGDPofthethreeprovincesinSCincreasedobviouslyduringthepast28years,especiallyinGuangdong,whichexhibitedthatthereissimultaneouscorrelationbetweenlightraindayswiththevariablesoflowcloudcoverandreleaseofaerosolsoverSCduring1960to2005.

简介：ＴＨＥ２－ＤＮＵＭＥＲＩＣＡＬＳＴＵＤＹＯＮＴＨＥＰＲＩＮＣＩＰＬＥＳＯＦＲＡＩＮ－ＥＮＨＡＮＣＥＭＥＮＴＡＮＤＨＡＩＬ－ＳＵＰＰＲＥＳＳＩＯＮＩＮＣＯＮＶＥＣＴＩＶＥＣＬＯＵＤＳＭａｏＹｕｈｕａ（毛玉华）ａｎｄＨｕＺｈｉｊｉｎ（胡志晋）ＴＨＥ２－Ｄ...

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：PossiblerelationshipsbetweenMJOandthesevererain-snowweatherinEasternChinaduringNovemberof2009areanalyzedandresultsshowthatastrongMJOprocessisoneofthestrongimpactfactors.MJOisveryactiveovertheIndianOceaninNovember2009.Especially,itmaintains9daysinMJOphase3,justcorrespondingtothetwostrongestrain-snowprocesses.CompositesofMJOeventsshowthatwhentheMJOconvectivecenterislocatedovertheIndianOcean,theprobabilityofrainfallissignificantlyincreasedandthetemperatureislowerthannormalineasternChina,whichisconsistentwiththesituationinNovemberof2009.Atmosphericcirculationanomaliesofmid-andhigher-latitudescanbeinfluencedbythetropicalMJOconvectionforcingandthisinfluencecouldberealizedbyteleconnection.WhentheMJOisovertheIndianOcean,itisfavorableforthemaintenanceofacirculationpatternoftworidgesversusonetroughatmid-andhigher-latitudes.Meanwhile,thewesternPacificsubtropicalhighisstrongerandmorewestwardthannormal,andasignificantconvectivebeltappearsovereasternEastAsia.AllthesecirculationanomaliesshowninthecompositeresultalsoappearedintheobservationsinNovember2009,whichindicatesthegeneralfeaturesofrelationshipsbetweentheMJOandthecirculationanomaliesovertheextratropics.Besidesthezonalcirculationanomalies,theMJOconvectioncanalsoleadtomeridionalcirculationanomalies.WhentheMJOconvectionislocatedovertheIndianOcean,thewesternPacificisdominatedbyanomalousdescendingmotion,andtheeasternEastAsiaiscontrolledbystrongconvergenceandascendingmotion.Therefore,ananomalousmeridionalcirculationisformedbetweenthetropicsandmiddlelatitudes,enhancingthenorthwardtransportationoflow-levelmoisture.Itispotentiallyhelpfultounderstandingandevenforecastingsuchkindofrain-snowweatheranomaliesasthatinNovember2009usingMJO.

简介：<正>The9thNortheastAsianYouthForumopenedonJuly22nd,2012attheInternationalYouthCenterinSeoul,Korea.Over60universitystudentsfromChina,JapanandKoreaplayedleadingrolesonthis6-dayforum.Withthethemeof"NatureandYouthExtra-curricularActivities",theForumwasdesignedandhostedbyMAR/Initiativesof

简介：

简介：Soilsusceptibilitytodetachmentandtransportsub-processesoferosionisgenerallycontroledbytheaggregatebreakdownmechanism.Measuringparticlesizeandaggregationtotheestimateerodibilitypotentialofsoilsisimportantundererosiverainfallconditions.TheAggregateSizeDistribution(ASD)isoneofthemostimportantdeterminantsofsoilstructurealongwithsoilorganicmattercontentfordescribingtheefficiencyofapplied,sustainablemanagementstrategies.Thisstudyaimedtocomparetheperformancesofthreedifferentaggregatesizedistributionmodelstopredictthecharacteristicaggregatesizeparameter(mediandiameter,D50)forerodedsedimentfrominterrillerosionprocessesofRain-SplashTransport(RST)andRaindropImpactedFlowTransport(RIFT).TheASDsof1143collectedsedimentsamplesfromtheRSTandRIFTprocessesweremeasuredandmodeledbytheLog-normal,Fractal,andWeibullapproaches.TheD50value,asacharacteristicparameterforaggregatesizedistributions,derivedfromthecumulativeASDcurvewascomparedforsoilsfromdifferentlandusetypesanddifferentslopeandrainfallintensityconditions.TheperformanceofeachmodelwasevaluatedusingtheMeanSquareError(MSE)andCoefficientofDetermination(R^2).TheWeibullapproachwasthemostaccuratemodelshowingthebestfitwiththelowestMSEvalues(0.0002≤MSE≤0.0048)andhavingthegreatestR2values(0.936≤R^2≤0.998)whencomparedwiththeLog-normalandFractalmodels.Herewith,forsemi-aridlanduseandsoil,specificshapeandscaleparametersfortheWeibulldistribution,therespectiveASDsweresuccessfullyre-generatedformodelingtheerodedsedimentofthesimulatedRSTandRIFTinterillprocesses.

简介：Weanalyzedcloudmicrophysicalprocesses’latentheatcharacteristicsandtheirinfluenceonanautumnheavyraineventoverHainanIsland,China,usingthemesoscalenumericalmodelWRFandWRF-3DVARsystem.Wefoundthatpositivelatentheatoccurredfarabovethezerolayer,whilenegativelatentheatoccurredmainlyunderthezerolayer.Therewassubstantiallymorepositivelatentheatthannegativelatentheat,andthecondensationheatinghadthemostimportantcontributiontothelatentheatincrease.Theprocessesofdeposition,congelation,meltingandevaporationwereallcharacterizedbyweakeningaftertheirintensification;however,thevariationsincondensationandsublimationprocesseswererelativelysmall.Themaincloudmicrophysicalprocessesforpositivelatentheatwerecondensationofwatervaporintocloudwater,thecondensationofrain,andthedepositionincreaseofcloudice,snowandgraupel.Themaincloudmicrophysicalprocessesfornegativelatentheatweretheevaporationofrain,themeltingandenhancedmeltingofgraupel.Thelatentheatreleasesduetodifferentcloudmicrophysicalprocesseshaveasignificantimpactontheintensityofprecipitation.Withoutthecondensationandevaporationofrain,thetotallatentheatingwoulddecreaseandthemoisturevariablesandprecipitationwouldreducesignificantly.Withoutdepositionandsublimation,theheatinginhighlevelswoulddecreaseandtheprecipitationwouldreduce.Withoutcongelationandmelting,thelatentheatingwouldenhanceinthelowlevels,andtheprecipitationwouldreduce.

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

简介：Theactivityoflowfrequencyoscillation(LFO)widelyexistsinEastAsiaduringtheperiodof1991excessivelyheavyrainovertheChangjiang-HuaiheRiverBasin(Jianghuai).BoththerainfallamountofJianghuaiandtheatmospherefromsubtropicalareatomid-highlatitudeshavethedominantperiodof10—20d,whiletheatmospheresintropicalareaandhighlatitudeshavethedominantperiodof30—60d.ComparedwithnormalMeiyuseason,theanomalyofthe1991Meiyuprocessmaybereflectedinthefollowingtwolowfrequencysynopticevents:(a)TheMeiyuprocessonsetsextremelyearly(intheseconddekadofMay,whichisnearlyonemonthearlierthaninnormalMeiyu)andisimmediatelyfollowedbythefirstepisodeofheavyrain.(b)InthefirstdekadofJuly,thereoccurstheheaviestepisodeofrainfallofthewholeMeiyuseason,anditiseventheheaviestrainfallfortherecent30yearsinChina.Forthesetwoperiods,correspondingtotheadjustmentoflarge-scalesituationfrom“doubleblockinghigh”to“bipolarblockinghigh”,thepropagationdirectionofLFOinEastAsiahasadistinctseasonalvariation,fromeastward/northwardpropagation(passingthroughJianghuai)duringthefirstepisodetowestward/southwardpropagationduringthethirdepisode.Oscillationsofdifferentfrequencybandsaresuperposedinphase.TheLFOactivityofthecoldandwarm/moistairsoverJianghuaicanbestrengthenedthroughthoseLFOpropagationprocessesinEastAsia,althoughtheymayhavedifferentdirectionsinthreeepisodes.Particularly,theeastward(westward)propagationinlowlatitudesmakesthesouthwest(southeast)airflowtransportintensivelythelowfrequencywarm/moistairtothesouthofJianghuaifromtheIndianOcean(tropicalWestPacificOcean)inthefirst(third)episode.Suchwarm/moistairsmeetandinteractwiththecoldairwhichvigorouslyinvadesJianghuaipersistently,andfinallythreeepisodesofheavyrainoccurinmodeofLFO.

简介：InthisstudytheQingweatherrecords"ClearandRainRecords"wereusedtoreconstructthe18thcenturysummer(June-August)precipitationandmonthlyprecipitationseriesofMay,June,July,andAugust.Thenatureoftheserecordsandthetechniqucoftransformingthemintonumericalcodesaredescribed.Theprocedureofconvertingthesedescriptiverecordsintoquantitativemonthlyprecipitationanditsscientificbasisaregivenindetail.Thereliabilityoftheobtaindprecipitationseriesisalsoex-amined.

简介：降雨在海表面上有二重要效果，包括咸度减少并且表面变得更不平，它在L乐队海表面放射率上有进一步的影响。用宝瓶座和TRMM3B42配对数据集的调查显示检索的海表面咸度(SSS)被现在的宝瓶座算法与数字模型产量相比低估，特别在高雨率的情况下。例如，当雨率是25mm/h时，在观察卫星的SSS之间的偏爱和数字模型SSS是约2。偏爱能被财务为导致雨的粗糙消除，它被产生雨的戒指波浪光谱通常建模。雨光谱将是进为雨影响的海表面放射率的模拟的小斜坡近似(SSA)模型的输入。与理论模型一起的比较显示对更合适的雨spectrumis的实验模型在模拟被使用。进一步，雨光谱的系数被与2year宝瓶座和TRMM配对数据集的观察适合模拟修改。计算证实海表面放射率以风速度和雨率增加。雨率导致的增加在低雨率和低风速度的情况中是快速的。最后，包括雨光谱的海表面放射率的一个修改模型被在2014年5月使用配对数据集建议并且验证。与观察相比，导致雨的海表面放射率的偏爱近似由修改modelis模仿了1e4,和RMSE比1e3稍微大。与使用更多的配对数据，在模型之间的thebias检索了海表面咸度和observationsmay进一步被改正，并且RMSE可以在低雨率和低风速度的情况中被归结为不到1。

简介：热带降雨测量的能力为测量降雨的使命(TRMM)卫星被在南部的中国在一个重降雨实验期间使用TMI-85.5GHz微波影像数据和降水数据检验。从有在有85.5GHz微波的TBB的一个小时的雨数量的分发的比较，大雨的中心与低TBB价值的一个区域相应，是清楚的。7gB分发的地点和形状类似于降水的，并且越大降雨率，越多降低TBB。统计分析证明在TBQ和雨率之间的相关系数否定、重要。特别，当雨率是超过7mm/h时，在TBQ和雨率之间的关联度是更重要的。TRMM/TMI-85.5G举办的结果表演测量对流大雨的极有能力。

简介：ByusingNCEP/NCARdailyreanalysisdataanddailyprecipitationdataof740stationsinChina,relationshipsbetweenthepositionvariationoftheWestPacificsubtropicalhigh(WPSH)andthediabaticheatingduringpersistentandintenserainsintheYangtze-HuaiheRiversbasinarestudied.TheresultsshowthatthepositionvariationofWPSHiscloselyassociatedwiththediabaticheating.Therearestrongapparentheatingsourcesandmoisturesinksinboththebasin(tothenorthofWPSH)andthenorthofBayofBengal(tothewestofWPSH)duringpersistentandintenserainevents.Inthebasin,Q1zbeginstoincrease3daysaheadofintenserainfall,maximizes2dayslaterandthenreducesgradually,butitchangeslittleafterprecipitationends,thuspreventingtheWPSHfrommovingnorthward.InthenorthofBayofBengal,2daysaheadofstrongrainfalloverthebasin,Q1zstartstoincreaseandpeaks1dayaftertherainoccurs,leadingtothewestwardextensionofWPSH.Afterwards,Q1zbeginsdecliningandtheWPSHmakesitseastwardretreataccordingly.Basedonthecompleteverticalvorticityequation,inmid-troposphere,theverticalvariationofheatinginthebasinisfavorabletotheincreaseofcyclonicvorticitynorthofWPSH,whichcounteractsthenorthwardmovementofWPSHandfavorsthepersistenceofrainbandsoverthebasin.TheverticalvariationofheatinginthenorthofBayofBengalisinfavoroftheincreaseofanti-cyclonicvorticitytothewestofWPSH,whichinducesthewestwardextensionofWPSH.

简介：Previousstudiesemphasizetheimportantroleofa'north-ridgeversussouth-trough'dipole(affectingthelatitudesfrom20°to75°NaroundtheTibetanPlateau)ofanomalousgeopotentialheight(Z)intheearly-2008abnormalcryogenicfreezing-rain-and-snoweventsinthesouthernpartofChina.ThepresentstudyintendstoextracttheleadingsignalfacilitatingthedipolebasedonthenumericaloutputsofafullZ-linearmodelfordiagnosingtheglobalZ.Usingthismodelbuiltonfullprimitiveequationsinspherical-isobariccoordinates,wecanfurthersplittheanomalyofZ-Zfζ-uβ(representingtheZcomponentnotexplicitlyassociatedwiththeCoriolisparameterfanditsmeridionalderivativeβ)into15components.Withthemodel-outputZfζ-uβ(mainlyaccountingforthedipoleunderthegeostrophicbalance)andZ-Zfζ-uβmatricesastheleftandrightsingularvectorsrespectively,amaximumcovarianceanalysis(MCA)isperformedtoextractthesignificant2-4-dayleadingsignalcarriedbytheMCAZ-Zfζ-uβmodeintheupstreamareaofthedipole.Thisleadingsignalismainlyattributedto1)theabnormallystrongwesterliescenteredaroundtheexitregionoftheAtlanticjet-streamand2)thecorrespondinganomalous950-300hPaanticyclonetothesouthoftheabnormallystrongcenterofwesterlies.Theenergyofthepositivewavecenteraroundthisjetexitregionfavorsthedownstreamnorth-ridgewhiletheenergyofthenegativewavecenterassociatedwiththeanomalousanticyclonefavorsthedownstreamsouth-trough.