简介：利用1961~2014年春季宁夏20个气象站的降水及NCEP再分析等资料,重点分析了不同分布型ElNino事件次年宁夏春季降水的差异。结果表明：由于ElNino事件在1990年代以后主要转为中部型,宁夏春季降水对ElNino的响应也发生了变化,由之前在ElNino发生次年春季降水偏多,转为次年春季降水偏少。东部型和混合型ElNino事件次年春季,500hPa高度距平场上欧亚中高纬地区环流分布及700hPa水汽输送条件,均有利于宁夏出现降水;而中部型ElNino事件次年春季,青藏高原南侧以偏西风为主,青藏高原东南侧相对湿度较低,不利于宁夏春季出现降水。

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简介：DuringthedevelopingphaseofcentralPacificElNio(CPEN),morefrequentTCgenesisoverthenorthwestquadrantofthewesternNorthPacific(WNP)isattributedtothehorizontalshiftofenvironmentalvorticityfield.SuchanorthwestwardshiftresemblestheLaNiacomposite,eventhoughfactorsthatcausetheshiftdiffer(intheLaNiacasetherelativehumidityeffectiscrucial).GreaterreductionofTCfrequencyoverWNPhappenedduringthedecayingphaseofeasternPacificElNio(EPEN)thanCPEN,duetothedifferenceoftheanomalousPhilippineSeaanticyclonestrength.TheTCgenesisexhibitsanupward(downward)trendoverthenorthern(southern)partoftheWNP,whichislinkedtoSSTandassociatedcirculationchangesthroughlocalandremoteeffects.

简介：ThenormalmodemethodisadoptedtodecomposethedifferencesbetweensimulationswithSST(seasurfacetemperature)anomahesovercentra-easternPacificandnormalSSTbyuseofanine-layerglobalspec-tralmodelinordertoinvestigateshort-rangeclimaticoscillationwithvarioustimescalesforcedbyElNinoduringthenorthernsummer.InvestigationshowsthatElNinomayhavethefollowinginfluenceonatmosphereonvariousspace-timescales.Extra-longwavecomponentsofRossbymodeforcedbyconvectiveanomalyoverequatorialwesternPacificresultingfromElNinoproduceclimaticoscillationonmonthly(sea-sonal)timescaleinmiddle-highlatitudesofSouthernandNorthernHemispheres;extra-longwavecomponentsofKelvinmodeforcedbySSTanomaliespropagatealongtheequator,resultingin30—60dayoscillationoftropicalandsubtropicalatmosphere;anditslongwavesmoveeastwardwithwesterly,resultinginquasi-biweekoscillation.

简介：Threeessentialfactorsofforestfire(firesource,environment,andlitter)weretakenasthepointofview,andhasapproachedtheforecastmethodofforestfireintropicalareaofsouthwestChinainamacroscopicscale.Thisstudysupportedbymathematicalmethodwasfromanewangle.Forexample,intheaspectofforestfireforecast,ithasbeenthoughtoverthatmostforestfireisartificialfire,whichhaslotsofrandomness.SoitcouldbestudiedinakindofMarkovrandomprocesses.Inthe...

简介：A6-layer,4°×5°horizontalresolutionglobaloceanmodelhasbeendesignedandimproved.Aftera100-yearin-tegration,anequilibriumstatehasbeenreachedfromtheuppertolowerlayers.Bytakingthemeanstateoflastl0mod-elyearsasclimaticstate,weanalyzedthecharacteristicsoftheseasonalvariationinourmodelintegration.Theresultsshowthatthesimulatedseasonalvariationissimilartotheobserved.Sothedesignofourmodelissuccessful.Then,us-ingthesimulatedclimaticstateoftheseasonalvariationastheinitialstate,andtheobservedstressandthermalstateastheatmosphericforcing,wesimulatedtheprocessofElNinoin1972—1973successfully.Thesimulatedresultsofsea-sonalvariationusingourmodelwillbepresentedinpartI.

简介：根据赤道东太平洋海温开始增温位置不同，可将E1Nino事件分为两类，本文运用χ^2检验分析这两类E1Nino事件与杭州降水，气温的相关关系，分析结果表明，两类E1Nino事件与杭州汛期降水和全年降水量以及7月平均气温关系密切。