简介：TheNCEP/NCARreanalysisdatahavebeenemployedtodiagnosevariationsofthezonalmeanflowinborealsummer.TwoleadingEOFmodesarefoundtodominatethespatialandtemporalchangesofthesummertimezonalmeanwindsinthetroposphere.EOF1showsthedistributionofzonal-meanflowanomalieswithhighervarianceintheNorthPolarRegion,whereastheEOF2showsthedistributionofzonal-meanflowanomalieswithhighervarianceintropicalandextra-tropicalregions.TheEOF1andEOF2haverespectivelytheperiodicitiessimilartothoseofAOandENSO.SignificantlagcorrelationshavebeenfoundbetweenEOF1andENSO,andbetweenEOF2andAO,intheseasonsincludingspring,autumn,andwinter.However,nosignificantcorrelationshavebeenfoundbetweenEOF1insummerandENSOinanyotherseasons,andbetweenEOF2insummerandAOinotherseasons,nomatterhowbigthelagthatrepresentsnumberofseasonshasbeenset.Theseresultssuggestthattheprincipalmodesofsummertimezonalmeanflowcouldbestatisticallyseparatedfromeachother.Hence,EOF1andEOF2arephysicallyrelatedtotheAOandENSOrespectively.Atheorycalledquasi-geostrophicnon-accelerationtheoremhasbeenusedtopartlyexplainthepossiblemechanismsofthemaintenanceofthetwoprincipalmodes.ThecompositedifferencesofthedivergenceofEliassen-Palmflux(E-Pflux)betweenpositiveandnegativeyearsasobtainedfromthetimeseriesofEOF1andEOF2displaythedistributionsthatcontributetothezonalmeanwindanomaliesrepresentedbyEOF1andEOF2,respectively.TheplanetaryotherthanthesynopticwavesdominatethebehaviorsoftheE-Pfluxes,suggestingthecrucialroleoftheplanetarywavesinthemaintenanceofthezonalmeanflowanomalies.Theresidualcirculationaswellasthefriction,whichcancelthedivergenceoftheE-Pflux,alsoplayanimportantroleinsomeplaces.TheseresultsareveryhelpfulforourbetterunderstandinghowtheanomalouszonalmeanflowsmaintainandhowtheENSOandAOinfluencetheglo

简介：热带季节内振荡和北极涛动的持续异常会对全球大气环流产生影响,同样会对东亚地区的旱涝造成影响。本文针对云南及周边地区近年来频繁出现的极端干旱事件进行了分析。发现当热带大气季节内振荡（MJO）和北极涛动（AO）两者持续异常时,会对云南的降水产生影响。2009/2010秋、冬、春3季连旱就是由MJO和AO出现极端异常（MJO异常不活跃;AO异常偏弱）造成的。2011年云南主汛期极端伏旱的产生则是由于MJO持续不活跃和西太平洋高压脊异常偏北造成的。

简介：Long-termintegrationsareconductedusingtheSpectralAtmosphericModel(referredtoasSAMIL),whichwasdevelopedintheLaboratoryforNumericalModelingforAtmosphericSciencesandGeophysicalFluidDynamics(LASG)intheInstituteofAtmosphericPhysics(IAP),withdifferentresolutionstoinves-tigatesensitivityoftheMadden-JulianOscillation(MJO)simulationstothemodel'sresolution(horizontalandvertical).Threeresolutionsofthemodel,R15L9,R42L9andR42L26,withidenticalphysicalprocesses,allproducedthebasicobservedfeaturesoftheMJO,includingthespatiotemporalspace-timespectraandeastwardpropagation.Nofundamentaldifferencesamongthesesimulationswerefound.ThisindicatesthatthemodelresolutionisnotadeterminingfactorforsimulatingtheMJO.Detaileddifferencesamongthesemodelingresultssuggest,however,thatmodelresolutioncansubstantiallyaffectthesimulatedMJOincertainaspects.Forinstance,atalowerhorizontalresolution,highfrequencydisturbanceswereweakerandthestructuresofthesimulatedMJOwerebetterdefinedtoacertainextent.AhigherverticalresolutionledtoamorerealisticspatiotemporalspectrumandspatialdistributionofMJOprecipitation.Meanwhile,increasingthemodel'sresolutionimprovedsimulationoftheclimatology.However,increasingtheresolutionshouldbebasedonimprovingthecumulusparameterizationscheme.

简介：一座大楼城市的流动上的密度的效果与RNGκ用一个CFD模型被调查-ɛ骚乱闭合计划。有不同的造的27个案例是密度参数(例如，大楼和街峡谷纵横比)数字地被模仿。当大楼的密度参数变化，不同流动政体出现。当街峡谷相对狭窄、高时，在垂直方向的二个相反旋转的旋涡被产生。沿着街的风速被大楼的长度主要影响。然而，以一座单个大楼的密度参数发现或概括街峡谷流动的特征是很困难的。这是因为复杂流动模式由于旋涡结构和旋涡数字的变化出现。平均卷的涡度大小是很好的指示物尽管有流动的强壮的相关性，在大楼的密度参数的变化上反映流动特征。平均卷的涡度大小是大楼的长度和街峡谷宽度的强壮的功能的多线性的回归表演。大楼的长度的增加减少街峡谷的涡度流动，当时，在街上，峡谷宽度增加的增加涡度。

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。

简介：BasedonChina’sobservationaldatain1951-1990,afterminimizingthepossiblebiasescausedbystationrelocationandurbanheatisland,thespatialandtemporaldistributionsoftrendsformaximumandminimumtemperaturesarestudied.Theresultsshowthatincreasingtrendsofmaximumtemperaturesareintheareaswestto95°E,andnorthtotheHuanghe(Yellow)River,whiledecreasingtrendsexistineasternChinasouthtotheYellowRiver.MinimumtemperaturesaregenerallyincreasingthroughoutChina,withdominantwarmingtrendsatthehigherlatitudes.Thisresultedinveryobviousdecreasingtrendsindiurnaltemperatureranges.Theperiodiccyclesareconsistentbetweenthemaximumandminimumtemperatures,butasymmetrictrendsareveryobvious.Thesignificantincreaseofminimum(nighttime)temperaturesreflectstheevidenceofenhancementofgreenhouseeffect.Furtheranalysisshowsthatthechangesofmaximumandminimumtemperaturesaremainlyrelatedtosunshinedurationandatmosphericwatervaporcontent.

简介：介绍了基于B／S结构的网上考试系统应用于气象部门的理论研究，并分析了系统总体结构，提供了一种应用SQL数据库以及ASP编程实现的网络考试系统，详细阐述了科目管理、随机生成试卷等模块的设计与实现，以及相关数据库表的结构。

简介：Thesimplelinearrelationshipbetweenclear-skyplanetaryandsurfacealbedocanbeadoptedforcertainaccuracy.Therearedifferentparameterizationschemesofatmosphericcorrectionfordifferentretrievalmodels.Inthispaper,severalrepresentativeretrievalmodelsarecomparedandtestedwithobservationaldatafromHEIhebasinFieldExperiment(HEIFE)inwesternChina.Someevaluationsandsuggestionsonimprovementareproposedformodelswhichwouldbemoreapplicabletoplateauandaridareas.

简介：Itispresentedthatthereisapumpingeffectatitsbaseinthedevelopmentprocessofacumulus.Inthestrongeststageofcumulusdevelopment,thepumpingismainlyproducedbythebuoyanceatthebase,andmaybetakenasthefirstapproximationoftheascendingspeedatthebase.Theresultsofnumericalcalculationsandsimulationsoffourobservedradarechoesshowthatasthefirstapproximation,theheightofair-masscumulusmaybesimulatedbyHaltinermodelintheabsenceofob-servedascendingspeedsatthebase,andtheHaltinermodelcanbecharacterizedbythesensitivityofthecumulusdevelopmenttothevirtualtemperatureexcessoverenvironmentatthebase.

简介：ThisworkinvestigatesthedistributionofhighwindsaboveBeaufortscale6intheoffshorezonesofChinausinghigh-resolutionsatellitemeasurements.AnumericalexperimentiscarriedoutinordertofindouttheeffectsofTaiwanIslandontheformationofstrongwinds.Theanalysisindicatesthatthedistributionofhighwindoccurrenceissimilartothatoftheaveragewindvelocityinwinter.Highwindstendtobeanchoredinspecialtopographicalregions,suchastheTaiwanStrait,theBashiChannelandthesoutheastcoastofVietnam.HighwindsoccurmuchmorefrequentlyoverthewarmerthanthecolderflankofKuroshiofrontasitmeandersfromTaiwantoJapan.Thefrequencyofhighwindsdecreasesdrasticallyinspring.TheTaiwanStraitmaintainsthelargesthighwindoccurrence.Besides,highwindsremainfrequentintheBashiChannel,thesoutheasttipofTaiwanIslandandthewarmerflankofKuroshiofront.Insummer,highwindsgenerallyoccurinfrequentlyexceptoverabroadregionoffthesoutheastcoastofVietnamnear10°Nandthefrequencytheredecreasesfromsouthwesttonortheast.HighwindsaroundTaiwanIslandpresentnearaxisymmetricdistributionwithlargerfrequencyalongsoutheast-northwestdirectionandsmallerfrequencyalongsouthwest-northeastdirection.Thedominantdirectionofhighwindsexhibitsacounterclockwisecirculationsurroundingtheisland.Thefrequencyofhighwindsincreasesrapidlyinautumnandalmostrepeatsthedistributionthatappearsinwinter.ThesimulationresultssuggestthattheeffectsofTaiwanIslandtopographyonhighwindsvarywithseasons.Inwinter,topographyisthemajorcauseofhighwindsinthesurroundingoceaniczones.HighwindsinbothTaiwanStraitandthesoutheastcorneroftheislanddisappearandthefrequencydecreasesgraduallyfromsouthtonorthwhentheterrainisremoved.However,insummer,highwindfrequencyderivedfromtwosimulationswithandwithoutterrainisalmostidentical.Weattributethisphenomenontothefactorswhicharerespon

简介：ThedistributionofmonthlymeanerrorofNMCmodelforecastsanditsseasonalvariationareinvesti-gated.Theratioofmonthlymeanerrortostandarddeviationisusedheretofindoutthattheregionwhereacorrectionofsystematicerrorisneededandappropriateismainlyinlowlatitudes.Theimprovement,afterthemodel’sverticalresolutionandsomephysicalparameterswerechangedfromApril1985,isinvestigated,andtheNMCoperationalmodelforecastshavealsocomparedwiththoseofECMWF.

简介：随着浙江省各地对人影业务的需求日益提高，人影作业量逐年增加，这对浙江如何科学管理人影业务提出了新挑战。基于B／S模式建设一套面向省市县的人影业务管理系统，解决了人影业务操作规范化，管理标准化、科学化，信息数据化，信息口径统一化等问题，一定程度上提高了工作效率，促进了人影业务现代化发展的目的。另外，系统还具备对业务工作实时监管和弹药安全审批等功能，增强了人影安全生产的监管能力。

简介：在极的坐标系统和适当假设基于barotropic原语方程，我们获得了在统一集体空气上的山论的强迫的数学方程包裹。与海和陆地的摩擦应力的考虑，假定在热带气旋的包裹速度在线性变化并且表面压力的分发是圆形的，一套方程被导出，它描述山论的斜坡错误的影响，在热带气旋的风领域上的热带气旋的中央压力误差和位置误差。台风Wipha(2007)被选择验证上述解释方法。结果证明气旋的山论的斜坡，摩擦系数，紧张和位置是在热带气旋的风信息的解释上有大影响的重要因素。动态解释方法给很好的结果，特别为沿海的区域。它对在热带气旋改进风地的预报适用。

简介：采用哈巴河县观测站1961—2008年逐月平均气温、平均最高、平均最低气温资料．利用一元回归和R／S方法，分析了哈巴河县四季和年平均气温、年平均最高气温、年平均最低气温的变化特征。结果表明：近48年以来，哈巴河县冬、夏、秋季平均气温及全年平均气温序列均表现为升温的趋势，其中冬季升温最为明显：四季和年平均最高和最低气温近48年来也呈上升趋势．并且四季和年平均最低气温的上升趋势比四季和年平均最高气温的上升趋势显著。经R／S分析表明，未来四季中夏、秋、冬季及年平均气温仍呈上升趋势且持续时间较长，而春季气温上升趋势不明显；四季和年平均最高、最低气温未来上升的趋势也将继续存在，且最低气温的持续性比最高气温的持续性长，夏、秋两季最低气温升温趋势相对其他两季较为明显，而夏、冬两季的最高气温的升温趋势相对其他两季较为明显。总之．近48年来哈巴河县气温总体变化趋势存在明显的hurst现象．未来这种现象也仍将持续。

简介：引言当前我国正积极筹备加入世界贸易组织(WTO),一旦加入,中国的一些农产品将受到国外农产品的严重冲击.在这种形势下,除了依靠政府制定有利于产业结构调整,稳定农民收入的政策外,生产者还应更加注重资源的合理利用,达到生态、经济、社会和生产的可持续发展.

简介：BasedontheCMAtropicalcyclone(TC)besttrackdataaswellasthereanalysisdatasetsfromtheNCEP/NCARandNOAA,thevariationcharacteristicsofTCnumberfrom1949to2013overthewesternNorthPacific(includingtheSouthChinaSea)areexamined.Notably,thetimeseriesofTCnumberexhibitsasignificantabruptchangefrommoretolessaround1995.ComparativeanalysisindicatesthattheenvironmentalfactorsnecessarytoTCformationalsochangesignificantlyaroundthemid-1990s.After1995,accompanyingwithanomalouswarmseasurfacetemperature(SST)inwesternequatorialPacific,aLaNia-likepatternintropicalPacificappearsobviously.However,comparedwiththeperiodbefore1995,theverticalupwardmovementdecreases,verticalshearoftroposphericzonalwindincreases,andsealevelpressure(SLP)rises,allofwhichareunfavorabletoTCformationandworktogethertomakeTCnumberreducemarkedlyafter1995.Furthermore,whenthetypicalinterannualmoreandlessTCsyearsareselectedinthetwoseparatestagesbeforeandafter1995,therelativeimportanceofoceanicandatmosphericenvironmentsininterannualTCgenerationisalsoinvestigatedrespectively.TheresultsimplythattheSSToverthetropicalPacificexertsrelativelyimportantinfluenceonTCformationbefore1995whereastheatmosphericcirculationplaysamoreprominentroleinthegenerationofTCafter1995.

简介：Asthestrongestsubseasonalatmosphericvariabilityduringborealwinter,threeremarkablesuddenstratosphericmajorwarming(SSW)eventsinthe2000sareinvestigatedintermsoftheBrewer–Dobsoncirculation(BDC)response.Ourstudyshowsthatthechangesofcross-isentropicvelocityduringtheSSWsarenotonlyconfinedtothepolarregion,butalsoextendtothewholeNorthernHemisphere:enhanceddescentinthepolarregion,aswellasenhancedascentinthetropics.WhentheaccelerationofthedeepbranchoftheBDCdescendstothemiddlestratosphere,itsstrengthrapidlydecreasesoveraperiodofonetotwoweeks.TheaccelerationofthedeepbranchoftheBDCisdrivenbytheenhancedplanetarywaveactivityinthemid-to-high-latitudestratosphere.DifferentfromtherapidresponseofthedeepbranchoftheBDC,tropicalupwellinginthelowerstratosphereacceleratesupto20%–40%comparedwiththeclimatology,20–30daysaftertheonsetoftheSSWs,andtheaccelerationlastsforonetothreemonths.Theenhancementoftropicalupwellingisassociatedwiththelarge-scalewave-breakinginthesubtropicsinteractingwiththemidlatitudeandtropicalQuasi-BiennialOscillation–relatedmeanflow.

简介：

简介：以应用为切人点，介绍用VB开发基于SQLSERVER的C／S软件中的系统配置、前后台连接、数据访问等实际问题的解决思路及实例。对数据库控件、数据库访问对象及ODBC三种数据库访问方法进行比较分析，得出在气象业务C／S应用系统开发中，ADO数据访问方法是一种较佳的选择。

简介：基于B/S架构建立了一个历史气象资料共享检索平台,后台采用MSSQLServer2005搭建数据库服务器,采用ArcGISServer9.3搭建WebGIS服务器,前台开发了一个多功能的资料检索界面,提供自定义条件的检索和多种统计方法,结合地理信息系统技术,设计了图表、图像、Excel表格等多种输出方式,为全省气象业务服务人员提供了一个方便实用的公共气象服务平台历史资料共享检索系统。