学科分类
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110 个结果
  • 简介:DISTRIBUTIONOFLOWFREQUENCYWAVESINNORTHPACIFICANDINTRASEASONALABNORMALITYOFTHEWESTERNPACIFICSUBTROPICALHIGHLiXingliang(李兴亮)(Me...

  • 标签: LOW FREQUENCY wave SUBTROPICAL high ABNORMALITY
  • 简介:EarlystudiessuggestedthattheAleutian-Icelandiclowseesaw(AIS)featuresmultidecadalvariation.Inthisstudy,themultidecadalmodulationoftheAISandassociatedsurfaceclimatebytheAtlanticMultidecadalOscillation(AMO)duringlatewinter(February-March)isexploredwithobservationaldata.Itisshownthat,inthecoldphaseoftheAMO(AMOI-),aclearAISisestablished,whilethisisnotthecaseinthewarmphaseoftheAMO(AMO[+).ThesurfaceclimateoverEurasiaissignificantlyinfluencedbytheAMO'smodulationoftheAleutianlow(AL).Forexample,theweakALinAMOI-displayswarmersurfacetemperaturesovertheentireFarEastandalongtheRussianArcticcoastandintoNorthernEurope,butonlyovertheRussianFarEastinAMO{+.Similarly,precipitationdecreasesovercentralEuropewiththeweakALinAMOI-,butdecreasesovernorthernEuropeandincreasesoversouthernEuropeinAMOI+.

  • 标签: Aleutian-Icelandic LOW seesaw ATLANTIC Multidecadal Oscillation
  • 简介:Inthispaper,anerrorsourceintheatmosphericcomponentoftheCZ(Cane-Zebiak)modelisdiscussed,whichismissingafreemodein“theexactsolutions”.However,theimprovedschemeisproposed,whichisthecomputationalschemewithadjustedwindorobserveduandvaslateralboundaries.Thesimulationsshowthatthesimulatedsurfacewindbytheimprovedschemestrong-lybearsresemblancetotheobservationexceptfortheareanearthewestandtheeastboundariesoftheintegratedarea.Theseresultssupporttheconclusionthatthewindstresssimulatedbytheim-provedschemewithlateralboundariesismuchbetterthanthatsimulatedbytheCZmodel,andshowthatinteractionbetweenlowandmiddlelatitudeshasanimportantinfluenceontheENSOvariabilityintheCZmodel.Therefore,consideringitsimpactontheCZmodelcanimprovecapa-bilityoftheCZmodelforsimulatingENSOvariability.

  • 标签: INTERACTION ENSO VARIABILITY error source ATMOSPHERIC
  • 简介:ATibetanozonelowwasfoundinthe1990saftertheAntarcticozonehole.Whetherthisozonelowhasbeenrecoveringfromthebeginningofthe2000sfollowingtheglobalozonerecoveryisanintriguingtopic.WiththemostrecentmergedTOMS/SBUV(TotalOzoneMappingSpectrometer/SolarBackscatterUltraViolet)ozonedata,theTibetanozonelowanditslong-termvariationduring1979-2010areanalyzedusingastatisticalregressionmodelthatincludestheseasonalcycle,solarcycle,quasi-biennialoscillation(QBO),ENSOsignal,andtrends.TheresultsshowthattheTibetanozonelowmaintainsandmaybecomemoresevereonaverageduring1979-2010,comparedwithitsmeanstateintheperiodsbefore2000,possiblycausedbythestrongerdownwardtrendoftotalozoneconcentrationovertheTibet.Comparedwiththeozonevariationoverthenon-Tibetanregionalongthesamelatitudes,theTibetanozonehasalargerdownwardtrendduring1979-2010,withamaximumvalueof-0.40±0.10DUyr1inJanuary,whichsuggeststhestrengtheningoftheTibetanozonelowincontrasttotherecoveryofglobalozone.RegressionanalysesshowthattheQBOsignalplaysanimportantroleindeterminingthetotalozonevariationovertheTibet.Inaddition,thelong-termozonevariationovertheTibetanregionislargelyaffectedbythethermal-dynamicalproxiessuchasthelowerstratospherictemperature,withitscontributionreachingaround10%ofthetotalozonechange,whichisgreatlydifferentfromthatoverthenon-Tibetanregion.

  • 标签: 南极臭氧洞 西藏 长期变化 统计回归模型 藏族地区 臭氧总量
  • 简介:基于轨道集成和轨道试穿方法,与不同精确,严肃模型的人物的影响在低地球轨道卫星的运动上被学习。方法和吸收重力的影响的效果为错误建模在上捣烂并且优雅卫星轨道,用线性并且实验加速建模的期刊和“叫theso的伪stochastic脉搏”当模特儿,也被分析。

  • 标签: 低地球轨道卫星 精密轨道测量 重力模型误差 轨道拟合
  • 简介:Usingfoursatellitedatasets(TOMS/SBUV,OMI,MLS,andHALOE),weanalyzetheseasonalvariationsofthetotalcolumnozone(TCO)anditszonaldeviation(TCO*),andrevealtheverticalstructureoftheOzoneLow(OV)overtheAsiancontinent.Ourprincipalfindingsare:(1)TheTCOovertheAsiancontinentreachesitsmaximuminthespringanditsminimumintheautumn.TheOzoneLowexistsfromMaytoSeptember.(2)TheOzoneLowhastwonegativecores,locatedinthelowerandtheupperstratosphere.Thelowercoreisnear30hPainthewinterand70hPaintheotherseasons.Theuppercorevariesfrom10hPato1hPaamongthefourseasons.(3)ThepositionoftheOzoneLowinthelowerandtheupperstratosphereovertheAsiancontinentshowsseasonalvariability.

  • 标签: OZONE LOW DOUBLE core ASIAN CONTINENT
  • 简介:同位素在在地球科学跟踪并且标明日期起一个重要作用,特别87Rb-86Sr系统。与地球科学的发展,整个岩石的分析斜面足够地满足要求因为科学研究和微量分析变得越来越重要。激光脱离多收集者诱导地联合的血浆mass-spectrometry(LA-MC-ICP-MS)广泛地由于它的低样品消费在微地区的分析被使用了,高精确性在矩阵上的situ和低要求,但是当它被严重优秀辨别和集体光谱干扰的各种各样的类型限制,精确地与高Rb/Sr比率和低Sr内容特别为样品测量Sr同位素作文仍然是困难的。因而,热电离mass-spectrometry(提姆)分析同位素的比率的最精确、精确的方法,仍然是分析Sr比率的最流行的方法,特别为有低Sr内容的样品。这篇论文在low-Sr的高精确的Sr同位素分析上做系统的评论地质的样品包括微采样的技术,极端低的程序的空白的化学方法和提姆测量技术。极端低的程序的空白和提姆的联合能被用来与ng大小执行样品的高精确的微量分析,它将无疑是为Rb-Sr地球年代学,地球化学和环境研究的一个重要方向。

  • 标签: 地质样品 同位素分析 锶同位素 高精度 电感耦合等离子体质谱 Rb/Sr比值
  • 简介:BasedontheTaylorseriesmethodandLi’sspatialdifferentialmethod,ahigh-orderhybridTaylor–Lischemeisproposed.Theresultsofalinearadvectionequationindicatethat,usingtheinitialvaluesofthesquare-wavetype,aresultwiththirdorderaccuracyoccurs.However,usinginitialvaluesassociatedwiththeGaussianfunctiontype,aresultwithveryhighprecisionappears.Thestudydemonstratesthat,whentheorderofthetimeintegralismorethanthree,thecorrespondingoptimalspatialdifferenceordercouldbehigherthansix.Theresultsindicatethatthereasonforwhythereisnoimprovementrelatedtoanorderofspatialdifferenceabovesixistheuseofatimeintegralschemethatisnothighenough.TheauthoralsoproposesarecursivedifferentialmethodtoimprovetheTaylor–Lischeme’scomputationspeed.Amorerapidandhighprecisionprogramthandirectcomputationofthehigh-orderspacedifferentialitemisemployed,andthecomputationspeedisdramaticallyboosted.Basedonamultiple-precisionlibrary,theultrahigh-orderTaylor–LischemecanbeusedtosolvetheadvectionequationandBurgers’equation.

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  • 简介:Atime-domainmethodisappliedtosimulatenonlinearwavediffractionaroundasurfacepiercing3-Darbitrarybody.ThemethodinvolvestheapplicationofTaylorseriesexpansionsandtheuseofperturbationproceduretoestablishthecorrespondingboundaryvalueproblemswithrespecttoatime-independentfluiddomain.AboundaryelementmethodbasedonB-splineexpansionisusedtocalculatethewavefieldateachtimestep,andthefreesurfaceboundaryconditionissatisfiedtothesecondorderofwavesteepnessbyanumericalintegrationintime.Anartificialdampinglayerisadoptedonthefreesurfacefortheremovalofwavereflectionfromtheouterboundary.Asanillustration,themethodisusedtocomputethesecond-orderwaveforcesandrun-uponasurface-piercingcircularcylinder.Thepresentmethodisfoundtobeaccurate,computationallyefficient,andnumericallystable.

  • 标签: TIME-DOMAIN METHOD boundary element METHOD wave
  • 简介:X-raydiffractionmethodsforestimatingthemetamorphicgradeofdiagenetic,anchizoneandepizoneinmetapelitesarereviewedandappliedtosamplesfroma7000m+boreholeinwesternChinaandsurfacesamplesfromthesurroundingZoigêarea.Kübler'sillitecrystallinity(IC)measurementsprovidemoreconsistentresultsthancalculatedvaluesofpercentageofilliteintheI/SmixedlayersandpercentageofI/Smixedlayers.Down-boreholeICvaluesdisplayatypicalburialmetamorphicrelationshipbetweenstratigraphiclevelandIC.Amethodforpreparingverylowgrademetamorphicmapsisdescribed,andisogradsplottedonaregionalgeologicalmapatselectedvaluesofIC,delineatingahightemperaturediageneticzone,ananchizone,andanepizone.ThemapshowsthatICvaluesarecontrolledbystratigraphiclevelinthenorthofthestudyarea(i.e.burialmetamorphism),andproximitytoanigneousintrusivebodyinthesouth(i.e.contactmetamorphism).

  • 标签: 伊利石结晶度 变质程度 中国西部 泥质岩 三叠系 火成岩侵入体
  • 简介:波浪方程波浪地数字建模技术被用于深层成像在高速度的暗岩的屏蔽的层下面是困难的观察。三个简单高速度的暗岩模型根据暗岩形成特征被设计。低频率的地震信号能够两个都渗透薄高速度的暗岩层并且减少衍射噪音的地震信号精力表演由不平的表面引起了的深层的思考的分析。一个完全的2D暗岩模型的模拟实验证实低频率的信号能被用来在高速度的暗岩层下面增加深层的成像的质量并且在低通行证的过滤器处理实际数据完成好结果。

  • 标签: 高速屏蔽层 玄武岩 低频信号 穿透力 成像数值模拟
  • 简介:Basedonthedailymeantemperatureand24-haccumulatedtotalprecipitationovercentralandsouthernChina,thefeaturesandthepossiblecausesoftheextremeweathereventswithlowtemperatureandicingconditions,whichoccurredinthesouthernpartofChinaduringearly2008,areinvestigatedinthisstudy.Inaddition,multimodelconsensusforecastingexperimentsareconductedbyusingtheensembleforecastsofECMWF,JMA,NCEPandCMAtakenfromtheTIGGEarchives.ResultsshowthatmorethanathirdofthestationsinthesouthernpartofChinawerecoveredbytheextremelyabundantprecipitationwitha50-areturnperiod,andextremelylowtemperaturewitha50-areturnperiodoccurredintheGuizhouandwesternHunanprovinceaswell.Forthe24-to216-hsurfacetemperatureforecasts,thebias-removedmultimodelensemblemeanwithrunningtrainingperiod(R-BREM)hasthehighestforecastskillofallindividualmodelsandmultimodelconsensustechniques.TakingtheRMSEsoftheECMWF96-hforecastsasthecriterion,theforecasttimeofthesurfacetemperaturemaybeprolongedto192hoverthesoutheasterncoastofChinabyusingtheR-BREMtechnique.ForthesprinkleforecastsovercentralandsouthernChina,theR-BREMtechniquehasthebestperformanceintermsofthreatscores(TS)forthe24-to192-hforecastsexceptforthe72-hforecastsamongallindividualmodelsandmultimodelconsensustechniques.Forthemoderaterain,theforecastskilloftheR-BREMtechniqueissuperiortothoseofindividualmodelsandmultimodelensemblemean.

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  • 简介:Inthispaper,five-yearsimulateddatafromalow-resolutionglobalspectralmodelwithtriangulartrunca-lionatwavenumber10areanalyzedinordertostudydynamicalfeaturesandpropagationcharacteristicsofintraseasonaloxillationsoverthemid-latitudesandthetropicalatmosphere.Thesimulationsshowthatthereisthe30-50dayperiodicoscillationinthelow-resolutionspectralmodelwithoutnon-seasonalexternalforcing,andspatialscaleoftheintraseasonaloscihationsisoftheglobe.Furtheranalysisfindsthatpropagationcharac-tersofintraseasonaloscillationsoverthemid-latitudesandthetropicsaredifferent.The30-50dayoscillationoverthetropicsexhibitsstructureofthevelocitypotentialwavewithwavenumber1inthelatitudinalandthecharacterofthetravelingwaveeastwardatspeedof8longitudes/day.However,the30-50dayoscillationsinmid-latitudeatmosphereexhibitphaseandamplitudeoscillationofthestandingplanetarywavesandtheyarerelatedtotransformofteleconnectionpatternsoverthemid-latitudes.Theenergyisnotonlytransferredbetweenthetropicsandthemiddle-highlatitudes,butalsobetweendifferentregionsoverthetropics.Basedontheanalysisof5-yearbandpassfiltereddatafroma5-layerglobalspectralmodelofJow-ordetwithtruncatedwavenumberl0,investigationisdoneofthesourceofintraseasonaloscillationsintheextratropicalmodelatmosphereanditsmechanism.Resultsshowthat(1)theconvectiveheattransferredeastwardalongtheequatorservesasthesourceoftheintraseasonaloxillationbothinthetropicalandtheextratropicalatmos--phere;(2)thevelocity-potentialwaveofazonalstructureofwavenumber1givesrisetooxillationindivergentandconvergentwindfieldsofadipole-formasseenfromtheequatorialIndianOceantothewesternPacificduringitseastwardpropagation,thusindicatingtheoscillationinthedipole-formheatsoure:e/sinkpattertl;(3)thetropicalheat-sourceoscillationisresponsibleforthe

  • 标签: :intraseasonal OSCILLATION teleconnectionnormal MODE GLOBAL spe
  • 简介:210Pbwasmeasuredduringthe3rdChineseNationalArcticResearchExpeditioncruisetoinvestigateitsspatialpatterninthewesternArcticOcean,aswellasitsrelationwiththethermoclineintheCanadianBasin.Thespecificactivitiesvariedfrom0.04to2.72,<0.013to4.37,and0.1to4.85Bq/m3fordissolved,particulate,andbulk210Pb,respectively,correspondingtorespectiveaveragesof0.65,0.43,and1.08Bq/m3.IntheCanadianBasin,theminimum210Pbactivitiesoccurredinthethermocline,whichwascharacterizedbylowtemperatureof-1.52°Candsalinityof33.1.Combiningthespatialdistributionof210PbandhydrographicalcharacteristicsinthewesternArcticOcean,thisscenariowasascribedtotheeffectivescavengingof210PbwhenthePacificwaterflowedacrosstheChukchiShelf.Quantitatively,thisinterpretationwassupportedbyboththeshorterresidencetimesandhigherscavengingefficiencies(SE)ofdissolved210PbovertheChukchiShelf.ThehighestSEvalueswereobservedintheHeraldShoalandbottomwatersovertheslope.

  • 标签: 铅-210 加拿大海盆 温跃层 楚科奇海 清理 北极科学考察
  • 简介:Yinshananticlineistheproductoftectono-dynamicdeformation-metamorphism.Alongtheaxisoftheanticlineexistsabrittle-ductileshearingzonewhichobviouslycontrolstheore-formation.Mineralizationoccursalongtheaxisoftheanticlineinawidthofabout1000m.Intheminingarea,volca-no-subvolcanicrocksofEarlyYanshanperiodaredividedintothreecycles:Iintermediateacidicdacitelavaanddaciteporphyry;Ⅱacidicamphibolelipariteandquartzporphyry;Ⅲintermediateandesiteporphyrite.AmongthemactivitiesofⅠandⅡcyclesaremoreintensiveandareintimatelyrelatedtothemineralization.Yinshanoredepositistheresultofcombinativeprocessesoftectono-dynamicandvolcano—magmatichydrothermalfluids,sothattherearetwocentersofmetallogeniczoning,onebeingtheaxialstrainzoneofYinshananticlinewhichisthecenteroffirstorder,andtheotherbeingporphyrystock,2ndorder.

  • 标签: YINSHAN POLYMETALLIC deposit multi-order and MULTI-CENTER
  • 简介:中等范围的天气的欧洲中心从微波手足更健全的、高分辨率动力学手足预报重新分析过渡期间(时代过渡期间)气象学和大小更健全,并且在观察系统气味卫星的地球上监视仪器的臭氧被使用分析截止的动态、化学的特征低(关口)在在七月初2007的东北中国上的事件。结果在100300hPa显示出上层的温暖核心的气旋的极的同温层的起源,与塑造漏斗的对流顶层侵入进联系了就在COL中心上面中间对流层。列臭氧和臭氧侧面上的同温层的侵入的影响用卫星大小被调查。当COL的紧张在2007年7月10日达到顶点时,全部的列臭氧(TCO)增加到达了最大值(4070杜)。这能动态地被归因于两个对流顶层(75%)的降下并且向下越过对流顶层(25%)同温层的臭氧搬运。tropospheric臭氧侧面的分析在关口中心前在上层的前面区域附近越过对流顶层为充满臭氧的同温层的空气的不可逆的搬运/混合提供了证据。这臭氧侵入由上面的tropospheric风经历了下游的运输,导致由在从向经由南朝鲜的北日本海的华东延长的宽广区域上的1216杜的TCO的另外的增加。气象学的分析也在中间和更低的对流层在气旋的发展前显示出同温层的侵入的领先。

  • 标签: 中国东北地区 卫星观测 化学特性 对流层顶 数值天气预报 地球观测系统
  • 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.

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  • 简介:Thelong-termtimeseriesanalysisoftheSST(seasurfacetemperature)intheEasternEquatorialPacificOceanandthemonthlyMSL(meansealevel)inthetropicalPacificOceanisconducted.Theirquasiperiodicandlow-frequencyoscillationfeaturesarerevealed.Thesignificantperiodsoflow-frequencyfluctuationsformonthlyMSLintheareaof20°N-20°Sarebetween43.5monthsand50.0months,approximatingcloselyto47.6monthswhichisthesignificantperiodofSSTintheEasternEquatorialPacificOcean.Fromtheresultsofspace-spectralanalysis,thelow-frequencyfluctationsofmonthlyMSLinthetropicalPacificOceanappeartohaveaanticlockwisecircularly-propagatingpattern,whichis,theEasternPacificOcean(off-shoreofMexico)→theareaofNEC(NorthEquatorialCurrent)→theWesternEquatorialPacificOcean→theareaofNECC(NorthEquatorialCounter-Current)→theEasternEquatorialPacificOcean.ThephasesofthepatterncorrespondtothoseofElNinocycle.Onthebasis

  • 标签: tropical PROPAGATING Eastern approximating forecast SHORE