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简介：Weinvestigatetheroleofcloudsandradiationinthegeneralcirculationoftheatmosphereusingamodeldesignedfor30-daypredictions.Comprehensiveverificationsof30-daypredictionsforthe500hPageo-potentialheightfieldhavebeencarriedout,usingthedatafromECMWFobjectiveanalysesthatcovertheperiodfromMay5toJune3,1982.Weperformthreemodelsimulations,includingexperimentswithinterac-tivecloudformation,withoutclouds,andwithoutradiativeheating.Thelattertwoexperimentsallowustostudytheeffectsofcloud/radiationinteractionsandfeedbacksonthepredictedverticalvelocity,andthemeridionalandzonalwindprofiles,averagedovera30-dayperiod.WedemonstratethattheHadleycirculationismaintainedbythepresenceofclouds.Theradiativecoolingintheatmosphereintensifiestheverticalmotioninlowlatitudesand,tosomeextent,alsostrengthenstheoverallmeridionalcirculation.Themeridionalwindsarecorrectlyreproducedinthemodelifcloudsareincorporated.Thezonalwindsaresignificantlyaffectedbycloudsandradiativecooling.Withoutanappropriateincor-porationofthesephysicalelements,themodelresultswoulddeviatesignificantlyfromobservations.Thepresenceofcloudsstrengthensthewesterliesinmiddleandhighlevels.InMay,thenortherlymovementofthejetstreamovereasternAsiais,inpart,associatedwiththepresenceofclouds.

简介：1.INTRODUCTIONAcidrainobservationsshowthatacidcloudwaterinShanghairegionappearsnotonly

简介：ByemployingtheimprovedT42L9spectralmodelintroducedbyNMC(Beijing)fromECMWFandutilizingtheFGGE-IIIbdatacoveringtheperiodof14—19June1979,theatmosphericresponsestotheabnormalsoilmoistureduringthemedium-rangeperiodhavebeenstudiednumerically.Accordingtotheinitialfieldat12GMT14June,afive-daynumericalexperimentunderdifferentconditionsofthesoilmoisturehasbeencarriedoutrespectively.ThemonthlymeanclimatologicalsoilmoistureforJunehasbeenusedinthecontrolexperimentintheinitialtimeanditchangeswithtimeaccordingtothemoisturebudgetequationatthelandsurface.Comparingwiththeexperimentswithdryorwetsoil.onecanconcludethat:1)Sourceofprecipitationovercontinentsinsummerconsistsoftheland-surfaceevaporationandthemoisturetransferfromoceans.Theirintensitiesarecomparableduringthemedium-rangetimescalewhenthesoilevaporatesitsmoisturesufficiently.Therefore,thesoilmoisturecaninfluencetheglobalprecipitationandthegeneralcirculationsignificantly;2)Byinfluencingthethermodynamicdifferencebetweenlandandsea,thesoilmoisturecanchangetheintensityofmonsoonandprecipitationdistribution;3)Theresponseoftheatmospheretotheabnormalsoilmoisturehasthecharacteristicsofgeographicaldistributionandnonlinearinteractions;4)Humanactivi-tiesontheworldcaninfluencetheenvironmentgreatly.

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简介：ＡＤＶＡＮＣＥＳＩＮＴＨＥＭＯＮＴＨＬＹ，ＳＥＡＳＯＮＡＬＡＮＤＹＥＡＲＬＹＬＯＮＧ－ＲＡＮＧＥＮＵＭＥＲＩＣＡＬＷＥＡＴＨＥＲＰＲＥＤＩＣＴＩＯＮ￥ＺｈｅｎｇＱｉｎｇｌｉｎ（郑关林）ＡＤＶＡＮＣＥＳＩＮＴＨＥＭＯＮＴＨＬＹ，ＳＥＡＳＯＮＡＬＡＮＤＹ...

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简介：为2007的模型模拟和水文学分析数据被使用在沿海的东亚上在hydrometeor形成上调查远程的荒芜的灰尘运输的影响。结果从香港和上海被分析，它是东亚的二个代表性的沿海的城市。远程的荒芜的灰尘运输主要在沿海的东亚上影响春天和夏天云和猛冲。在春天，云和猛冲主要来自大规模冷凝作用并且主要被灰尘从Gobi，撒哈拉沙漠，和一种羚羊沙漠影响。这些荒芜的灰尘能参予降水在以内并且在云下面。在更低的纬度，灰尘粒子主要充当水原子核。在更高的纬度，他们充当水原子核和冰原子核。大规模云和猛冲上的Gobi，撒哈拉沙漠，和一种羚羊灰尘的效果在更高的纬度变得更强壮。在夏天，在沿海的东亚上的云和猛冲主要来自传送对流并且主要被灰尘从Taklamakan影响，阿拉伯，并且Karakum-Kavir沙漠。大多数Taklamakan灰尘粒子能作为冰原子核在对流的云以内参予降水，当阿拉伯时，Karakum-Kavir灰尘粒子在云下面在降水仅仅作为水原子核参与。对流的云和猛冲上的Taklamakan灰尘的效果在更低的纬度变得更强壮。所有荒芜的灰尘，那从Gobi和Taklamakan沙漠有相对最大的影响。Gobi灰尘由在更高的纬度影响泉水云在沿海的东亚影响气候变化。

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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：AnapproachisproposedforpredictingturningandaccelerationmotiontrendofthetropicalcyclonesovertheSouthChinaSeafor72hintheextrapolatedtrackcoordinates.Cross-track(CT)andalong-track(AT)componentsaredefinedaccordingtothepersistentlyextrapolatedtrackcoodinatesbasedonobservedpositionsattheinitialandpast24htimes.Akindofstraight-forwardmeasuremaybeprovidedwithCTandATcomponentsfortyphoonturningmotionandac-celerationmotion.Canonicalcorrelationanalysis(CCA)isperformedtorevealthecorrelaotionsbe-tweentropicalcyclonetracksandenvironmental500hPageopotentialheightfields.Astepwisedis-criminateanalysistechniqueisadoptedtoderivetheclassificationfunctionsoftherespectivethreecategoriesforATandCTcomponents.Especially,categoricalcombinationsofCTandATcompo-nentsaredividedintopossible9regionscorrespondingwithtropicalcyclonebehaviors.Notonlycan9motiontrendsofatropicalcyclonebepredicted,butalsothelocationanditsmaximumerroratleastincertaindirectionareavailable.Theperfectprediction(PP)verificationsindicatethatthepercentcorrectsfortheCTandATcategoriesare67%and69%intheindependentsamples,73%and53%inthedependentsamples,respectively,higherthanthatof33.3%forrandomchance;moreover,therateforsuccessfullyforecastingthatinwhichoneofthenineregionsthetropicalcy-cloneswillfallat72hisabout40%,alsohigherthanthestochasticprobabilityof11%.Themethodhasbeenprovedtobeskillfulandpromising.

简介：Daily850-hPameridionalwindfieldsinEastAsiafromMarchtoSeptember2002wereusedtoestablishamodeloftheprincipaloscillationpattern(POP).Thismodelwasthenusedtoconductindependentextended-rangeforecastsoftheprincipaltemporalandspatialvariationsinthelow-frequencymeridionalwindfieldonatimescaleof20-30days.ThesevariationsaffecttheoccurrenceofheavyprecipitationeventsinthelowerreachesoftheYangtzeRivervalley(LYRV).Theresultsof135forecastexperimentsduringthesummerhalfyearshowthatthepredictedandobservedanomaliesarestronglycorrelatedataleadtimeof20days(meancorrelationgreaterthan0.50).Thisstrongcorrelationindicatesthatthemodeliscapableofaccuratelyforecastingthelow-frequencyvariationsinmeridionalwindthatcorrespondedtothe3heavyprecipitationeventsintheLYRVduringthesummerof2002.Furtherforecastexperimentsbasedondatafrommultipleyearswithsignificant20-30-dayoscillationsshowthatthesepredictionmodesareeffectivetoolsforforecastingthespace-timeevolutionofthelow-frequencycirculation.ThesefindingsofferpotentialforimprovingtheaccuracyofforecastsofheavyprecipitationovertheLYRVatleadtimesof3-4weeks.