简介：Longseriesofdailyweatherdataarefrequentlyneededtoevaluatediachronicclimaticimpactonwaterresources,theeffectsofwatershedchangesonhydrologyandtouseinavarietyofweatherandgeneralcirculationmodels.AcomputergenerationmodelcalledWGENthatwasdevelopedintheUnitedStatesofAmerica,wasmodifiedinthisstudyandappliedtoNigerianweatherdataspanningtheperiodbetween1969to1988andcovering17siteslocatedinthedifferentclimaticzonesinNigeria.Themodelgeneratedthemonthlymeanmaximumandminimumtemperatures,solarradiation,totalrainfall,andnumberofwetanddrydayswithhighaccuracy,95%ofthetimes.TheMann-WhitneyU-testrevealedthatthenumberofmonthsperyearforwhichobservedandgeneratedweathervariablesweresignificant,waslessthan4inmajorityofthesites.

简介：ＳＯＭＥＦＥＡＴＵＲＥＳＯＦＡＮＥＷＧＥＮＥＲＡＴＩＯＮＯＦＵＰＰＥＲ－ＡＩＲＯＢＳＥＲＶＡＴＩＯＮＳＹＳＴＥＭＨｕａｎｇＢｉｎｇｘｕｎ（黄炳勋）ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒｉｃＳｏｕｎｄｉｎｇＡＢＳＴＲＡＣＴＳｏｍｅｆｅａｔｕｒｅｓｏｆ...

简介：Typhoon-inducedheavyrainsaremostlystudiedfromtheviewpointofupper-levelwesterlytroughs.Itisworthwhiletoprobeintoacasewheretherainiscausedbytropicalcyclonesystem,whichismuchheavier.DuringAugust3~5,1996,anunusuallyheavyrainstormhappenedinthesouthwestofHebeiprovince.Itwascausedby3mesoscaleconvectivecloudclustersontheperipheryofatropicalcycloneotherthanthedirecteffectsofawesterlytrough.Generatinginaweakbaroclinicenvironmentthatisunstablewithhighenergy,thecloudclustersweretriggeredofffordevelopmentbyunstableageostrophicgravitywavesinthelow-levelsoutheastjetstreamontheperipheryofthetyphoon.Therewasaverticalcirculationcellwithhorizontalscalecloseto1000kmbetweentherainstormareaandwesterlytroughinnortheastChina.AsshowninacomputationoftheQvectoroffrontogenesisfunction,thecirculationcellformsamechanismoftransformingenergybetweentheareaofinterestandthewesterlytroughsystemfartherawayinnortheastChina.Studyofwatervaporchartindicatesthathigh-latitudetroughsinthenortheastportionoftherainmigratetothesoutheasttoenhanceanti-cyclonicdivergenceinupper-levelconvectionovertheareaofheavyrainandcauserainclusters,short-livedotherwise,todevelopvigorously.Itisactingasanamplifierinthiscaseofunusuallystrongprocessofrain.

简介：Byutilizingthebarotropicvorticityequationincludingeffectsoforographyandhorizontaldiffusion,thelinearizedequationsdescribingsymmetricandantisymmetricmotionsandtheiranalyticsolutionsarepre-sented.Itcanbefoundfromthesolutionsthatnomatterwhatkindofmotionmaybe,eachsolutionconsistsofthreewaves,namely,Rossbywaverelatedtoinitialvalues,marchingwavepropagatingatRossbywavevelocityandstationarywave.Thelattertwoarecloselyrelatedtoorographyandhorizontaldiffusion.However,ifthemotionissymmetricattheinitialinstant,thentheantisymmetriccomponentsoforographyandofhorizontaldiffusionarelikelytoleadtothegenerationofantisymmetricmotion.Inthesteadystate,thesymmetricflowisconnectedwithsymmetricorographyandhorizontaldiffusionandtheantisymmetricflowwithantisymmetricorographyandhorizontaldiffusion.Further,inordertoverifytheaboveanalysis,threenumericalexperimentshavebeenmade.Theresultsshowthatantisymmetricorographycanproduceantisymmetricmotion.Finally,theatmosphericinteractionsbetweenNorthernandSouthernHemispheresarediscussed.

简介：从卫星导出的大气的不稳定性信息在预报的短期的天气起一个重要作用，特别预报严重对流暴风雨。为为朝鲜多种用途的地球同步的卫星节目的天气卫星的下一代，一台新成像仪器被开发了。尽管这台成像仪器没被设计执行完整的发出声音的使命，它的能力是有限的，它的多光谱的红外线的隧道在垂直发出声音上提供信息。为了从大部分充分利用观察数据，改进了成像器的空间与时间的分辨率，为大气的不稳定性的推导的一条人工的神经网络途径的可行性被调查。有前馈控制和背繁殖训练算法的多层的视感控器模型显示出相当敏感回答到训练数据集和模型建筑学的选择。通过有7197独立侧面的小心地选择的训练数据集的广泛的性能测试，模型体系结构被选择分别地为隐藏的节点，时代的数字，和学习的率的数字是12，5000，和0.3。选择模型给330Jkg的一个吝啬的绝对错误，RMSE，和关联系数-1,420Jkg-1,并且0.9分别地。可行性进一步从一台类似的仪器经由模型的申请被表明到真实观察数据与计划成像器有可比较的观察隧道。

简介：ASouthChinaSea(SCS)localTC(SLT)isdefinedasatropicalcyclone(TC)thatformswithintheSCSregionandcanreachthegradeoftropicalstorm(TS)orabove.ThestatisticalfeaturesoftheSLTsfrom1985to2007areanalyzedfirst.ItisfoundthatovertheSCSabout68%oftheTCscandevelopintoTSs.TheSLTintensityisrelativelyweakandassociatedwithitsgenesislatitudeaswellasitstrack.TheSLTmonthlynumberpresentsaseasonalvariationwithtwopeaksinMayandJulytoSeptember.BasedonthedailyheatfluxdatafromtheWoodsHoleOceanographicInstitution_ObjectivelyAnalyzedair-seaFluxes(WHOI_OAFlux)inthesameperiod,theair-seaexchangeduringtheprocessofgenerationanddevelopmentoftheSLTisstudied.Resultsshowthattheheatfluxesreleasedtotheatmosphereincreasesignificantlydaybydaybeforecyclogenesis.TheoceantothesouthtotheTCcenterprovidesthemainenergy.AlongwiththedevelopmentofSLT,theregionswithlargeheatfluxesspreadclockwisetothenorthofTC,whichreflectstheenergydispersionpropertyofvortexRossbywavesintheperipheryoftheTC.OncetheSLTformstheheatfluxesarenotintensifiedasmuch.Duringthewholeprocess,thenetheat,latentheatandsensibleheatfluxdisplayasimilarevolution,whilethelatentheatfluxmakesamaincontributiontothenetheatflux.Themaximumair-seaheatexchangealwaysoccursattheleftsideoftheTCmovingdirection,whichmayreflecttheinfluenceoftheSCSsummermonsoononTCstructure.