简介:ThisstudyexaminesthemodulationoftropicalcyclogenesisovertheSouthChinaSea(SCS)bytheElNio-SouthernOscillation(ENSO)Modokiduringtheborealsummer.Resultsrevealthatthereweremoretropicalcyclones(TCs)formedovertheSCSduringcentralPacificwarmingyearsandlessTCfrequencyduringcentralPacificcoolingyears.Howdifferentenvironmentalfactors(includinglow-levelrelativevorticity,mid-levelrelativehumidity,verticalwindshear,andpotentialintensity)contributetothisinfluenceisinvestigated,usingagenesispotential(GP)indexdevelopedbyEmanuelandNolan.CompositeanomaliesoftheGPindexareproducedforcentralPacificwarmingandcoolingyearsseparately,whichcouldaccountforthechangesofTCfrequencyovertheSCSindifferentENSOModokiphases.Thedegreeofcontributionbyeachfactorisdeterminedquantitativelybyproducingcompositesofmodifiedindicesinwhichonlyoneofthecontributingfactorsvaries,withtheotherssettoclimatology.Theresultssuggestthattheverticalwindshearandlow-levelrelativevorticity,whichareassociatedwiththeENSOModoki-inducedanomalouscirculationsinMatsuno-Gillpatterns,makethelargestcontributionstotheENSOModokimodulationoftropicalcyclogenesisovertheSCSasimpliedbytheGPindex.TheseresultshighlighttheimportantrolesofdynamicfactorsinthemodulationofTCfrequencyovertheSCSbytheENSOModokiduringtheborealsummer.
简介:VariationsinGuangzhou’saerosolopticalcharacteristicsandtheirpossiblecausesarestudiedagainstthelarge-scalebackgroundofSouthChinaSeasummermonsoons(SCSSM)usingaerosoldataderivedfromPanyuAtmosphericCompositionWatchStationinGuangzhouandtheNationalCentersforEnvironmentalPrediction/NationalCenterforAtmosphericResearch(USA).Thedataisreanalyzedtodevelopacompositeanalysisandperformphysicaldiagnoses.AnalysisoftheresultsshowsthataerosolextinctioninGuangzhoufirstincreasesthendecreasesduringtheactiveperiodofaSCSSM,withvariationsinthestratificationoftheplanetaryboundarylayer(PBL)andenvironmentalwindsplayingimportantrolesinaffectingGuangzhou’saerosolopticalcharacteristics.RegionaldiabaticheatingandanomalouscycloniccirculationsexcitedbymonsoonconvectioninduceenvironmentalwindanomaliesthatsignificantlymodifythestratificationofthePBL.
简介:由使用常规气象学的数据,物理数量域,卫星图画和Doppler雷达回波数据,我们分析中央规模特征和在云南的重降水进程在早夏天在海湾上由暴风雨引起了的4successive的条件。结果证明在海湾上的暴风雨的生活是平常的2或3天和暴风雨的云顶温度总是在-65℃下面。在海湾上的暴风雨影响云南bymesoscale对疗簇,在外设的云系或削弱搬到东北的本身。西藏的高原砍线和旋涡,NE-SW集中隧道和西南风集中供应有利发行量背景和动态条件。关于Doppler雷达回波有许多普通特征,有关于到东方到的35-45dBZmove的紧张的絮凝的回响在云南生产连续降水,并且中央与高度放大西南喷气和风V字形物戒指的特征不仅是有利的搬运暴风雨在海湾上带到北方的温暖、潮湿的气流,而且对对流开发有利。
简介:TheSouthChinaSea(SCS)andtheArabianSea(AS)arebothlocatedroughlyinthenorthtropicalzonewitharangeofsimilarlatitude(0°–24°N).Monsoonwindsplaysimilarrolesintheupperoceaniccirculationsofthebothseas.Butthedistinctpatternsofchlorophylla(Chla)concentrationareobservedbetweentheSCSandtheAS.TheChlaconcentrationintheSCSisgenerallylowerthanthatintheASinsummer(June–August);thesummerChlaconcentrationintheASshowsstrongerinterannualvariation,comparedwiththatintheSCS;Moderateresolutionimagingspectroradiometer(MODIS)-deriveddatapresenthigheratmosphericaerosoldepositionandstrongerwindspeedintheAS.Andithasalsobeenfoundthatgoodcorrelationsexistbetweentheindexofthedustprecipitationindicatedbyaerosolopticalthickness(AOT)andtheChlaconcentration,orbetweenwindandChlaconcentration.TheseimplythatthewindandthedustprecipitationbringmorenutrientsintotheASfromthesky,thesub-layerorcoastregions,inducinghigherChlaconcentration.TheresultsindicatethatthewindvelocityandthedustprecipitationcanplayimportantrolesintheChlaconcentrationfortheASandtheSCSinsummer.HoweveraerosolimpactisweakonthebiologicalproductivityinthewestSCSandwind-inducedupwellingisthemainsource.
简介:Theresultsoftwoballoonsoundingsduringthesummerandautumnof1993fromtheXiangheObservationStationarebeingutilizedinastudyofthetemporalandspatialdistributionoftheatmosphericaerosols.Theballoon,gondola,instrumentationandatmosphericconditionsduringtheobservationperiodaredescribed.Thetemporalandspatialcharacteristicsofaerosolconcentration,sizeratio,mixingratio,andsizedistributionforbothtroposphereandstrato-spherearepresentedandanalyzed.
简介:夏天从1961~2004的Qinghai西藏高原上的97个气象学的车站的逐日的降水数据被选择通过积累的变化分析时间空间的分发,关联分析,回归分析,empir
简介:appendicularians上的桡脚类的动物的潜在的抑制在领域和试验性的条件里被发现。appendicularians和planktonic桡脚类的动物的丰富和分发在华南海(SCS)的西北大陆人架上在夏天期间与他们的关联的参考被学习。基于地形学和调查区域的水质量,它被划分成三个分区:区域我(东方Leizhou半岛的沿海的水)与低温度,咸度和高叶绿素一(Chl一)集中,有低温度的区域II(东方的沿海的水和东南海南岛),高咸度和中等Chl集中和区域III(近海从Leizhou半岛流水到海南岛)与高温度,高咸度和低Chl集中。appendicularians和桡脚类的动物的种类丰富增加了从对沿海近海水,和高价值在区域III被观察。appendicularian和桡脚类的动物丰富的分发通常减少了从对沿海近海水,与最高的价值在区域我。我们的结果建议appendicularians和桡脚类的动物的分发模式显著地不同,由于物理、生物的因素的影响。appendicularians上的远洋的桡脚类的动物的否定影响没被发现基于在在SCS的西北大陆人架中的situ数据。
简介:WepresentamodelforpredictingsummertimesurfaceairtemperatureinNortheastChina(NESSAT)usingayear-to-yearincrementalapproach.Thepredictedvalueforeachyear'sincreaseordecreaseofNESSATisaddedtotheobservedvaluewithinaparticularyeartoyieldthenetforecastNESSAT.Theseasonalforecastmodelfortheyear-to-yearincrementsofNESSATisconstructedbasedondatafrom1975-2007.Fivepredictorsareused:anindexforseaicecoverovertheEastSiberianSea,anindexforcentralPacifictropicalseasurfacetemperature,twohighlatitudecirculationindices,aswellasaNorthAmericanpressureindex.AllpredictorsareavailablebynolaterthanMarch,whichallowsforcompilationofaseasonalforecastwithatwo-monthleadtime.ThepredictionmodelaccuratelycapturestheinterannualvariationsofNESSATduring1977-2007withacorrelationcoefficientbetweenthepredictedandobservedNESSATof0.87(accountingfor76%oftotalvariance)andameanabsoluteerror(MAE)of0.3℃.Across-validationtestduring1977-2008demonstratesthatthemodelhasgoodpredictiveskill,withMAEof0.4℃andacorrelationcoefficientbetweenthepredictedandobservedNESSATof0.76.
简介:我们在东亚(EA)上在夏天intraseasonal摆动(ISO)的27年的强迫的模拟评估GAMIL1.1.1的表演西方的诺思太平洋(WNP)。评价基于二项措施:climatologicalISO(CISO)和短暂ISO(TISO)。CISO是对年度周期锁阶段并且描述季节的行军的ISO部件。TISO是逐年变化的ISO部件。模型相当捕获ISO的许多观察特征,包括逐步向北方CISO的雨带进展,在华南海菲律宾的海(SCS-PS)和长江盆(YRB)的TISO的主导的频率,向北方3050天的TISO的繁殖并且向西在SCS-PS上的1225天的TISO模式的繁殖,和在YRB上的三个主要TISO模式的带的宣传特征。然而,模型有著名缺乏。这些包括与CISO联系的华南海季风的早发作,太快向北方到40°N和10°N的CISO信号南方的缺席的从20°N的CISO的繁殖,3050天的TISO模式的缺乏的东方繁殖和在YRBTISO模式的向南方的繁殖的缺席。作者发现在ISO模拟的缺乏是仔细与模型在平均数的偏爱有关说,建议模型的改进意味着状态为intraseasonal变化的现实主义的模拟是关键的。
简介:东方亚洲冬季季风(EAWM)的可变性能被划分成ENSO相关的部分(EAWMEN)和ENSO无关的部分(EAWMres)。在腐烂的关系ENSO上演的ENSO东方亚洲夏天季风(EASM)上的EAWMres的影响在现在的学习被调查。完成这,ENSO基于EAWMres被划分成四个组:(1)弱EAWMres-ElNi?o(WEAWMres在);(2)强壮的EAWMres-ElNi?o(SEAWMres-在);(3)弱EAWMres-LaNi?一(WEAWMres行);(4)强壮的EAWMres-LaNi?一(SEAWMres行)。合成结果证明EAWMres可以为WEAWMres在和SEAWMres行在东亚上提高大气的回答到ENSO。相应低级逆旋风(气旋)在西方的诺思太平洋(WNP)上的异例把Ni与El联系了?o(LaNi?一)趋于强壮。重要地,这个特征可以坚持直到下列夏天,引起在为WEAWMres在案例的北中国并且在为SEAWMres行案例的西南的中国的丰富的降雨。为SEAWMres在和WEAWMres行组,相反,EAWMres趋于削弱与ElNi联系的大气的发行量异例?o或LaNi?一。在这些,情况,异常WNP反气旋或气旋趋于被减少并且限制了降低纬度,它为WEAWMres行为SEAWMres在并且在西南的中国在北中国导致缺乏的夏天降雨。进一步的学习建议异常EAWMres可以在热带以外的海表面温度异例上有效果,它坚持直到随后的夏天并且可以防碍ENSO的影响。
简介:Theimportanteffectsoflocalland-seathermodynamiccontrastbetweentheSouthChinaSea(SCS)andIndochinaPeninsulaonSCSsummermonsoononsetarepreliminarilystudiedbyusingtwosetsofSSTAtestsandtwoidealtestsinregionalclimatemodel.TheresultshowsthatwarmSSTintheSCSinwinterandspringisfavorablefortheformationofmonsooncirculationthroughoutalllevelsoftheatmosphereoverthesea,whichhastenstheonsetofSCSsummermonsoon.TheeffectsofcoldSSTaregenerallytheopposite.Thelocalland-seacontrastintheSCSisoneofthepossiblereasonsforSCSsummermonsoononset.Superposeduponlarge-scaleland-seathermodynamicdifferences,itfacilitatestheformationofout-breakingonsetcharacteristicsofSCSsummermonsoonintheSCSarea.
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简介:ByusingNCEPGODASmonthlyseasurfaceheight(SSH)and160-stationmonthlyprecipitationdatainChina,theseasonalandinterannualcharacteristicsofSSHareanalyzedoverthetropicalPacific,andcorrelationsbetweenSSHandsummerrainfallarediscussed.Theresultsareshownasfollows:(1)ThetropicalPacificSSHtakesona'V'patternintheclimaticfieldwithaneastwardopening,anditishigherinthewesternpart(inthenorthwesternpart)thanintheeasternpart(inthesouthwesternpart).Thehigh-valueareasaremorestableinthenorthwest,andthevaluerange(greaterthan0.8m)islargerinspringandsummerthaninautumnandwinter.Thehigh-valueareainthesouthwesternpartisthelargest(smallest)andmorenortherly(southerly)inspring(summer).SSHishigherinspringandautumnthaninsummerandwinterovertheequatorialzone.(2)TheinterannualanomaliesoftheSSHarethestrongestoverthetropicalwesternandsouthwesternPacificandarestrongerinwinterandspringthaninsummerandautumn.TheinterannualanomaliesarealsostrongovertheequatorialmiddleandeasternPacific.Thedistributionrangesarelargerandtheintensitiesarestrongerintheautumnandwinter.ThereisacloserelationshipbetweentheSSHinterannualanomaliesandENSOeventsinautumn,winterandspring.(3)WhenENSOeventstakeplaceinwinter,accordingtothesimultaneousrelationshipamongthetropicPacificSSH,850hPawindfieldsandthesummerprecipitationofChina,itcanbepredictedthattheprecipitationwillbesignificantlymorethannormaloverthesouthoftheYangtzeRiver,especiallyoverDongtingLakeandPoyangLakeregion,easternQinghai-TibetPlateau,Yangtze-HuaiRiverValley,easternpartofInnerMongoliaandlessthannormalovertheareaofGreatBandofYellowRiver,NorthChinaandSouthChinainsuccessivesummers.
简介:AimtolinkingthevariabilityofdroughtinnorthwestChinatotheoceanicinfluenceofNorthAtlanticSSTsatthebackgroundofglobalwarmingandattheregionalclimatechangeshiftingstages,yeararidityindexvariationsinnorthwestChinaandsummerNorthAtlanticseasurfacetemperature(SST)variationsareexaminedforthe44aperiodof1961-2004usingsingularvaluedecomposition(SVD)analysis.ResultsshowthattheSSTanomalies(SSTA)intheNorthAtlanticinsummerreflectedthreebasicmodels.ThefirstSVDmodeofSSTpatternshowsadipole-likevariationwiththepositivecenterlocatedatsouthwestandnegativecenteratnortheastofextratropicalNorthAtlantic.AnditstronglyrelatestothepositivetrendinAIvariationinnorthwestChina.ThesecondcoupledmodesdisplaythecoherentpositiveanomaliesinextratropicalNorthAtlanticSSTandthemarkedoppositetrendofAIvariabilitybetweennorthandsouthofXinjiang.Inaddition,thelagcorrelationanalysisofthefirstmodeofSSTAandgeopotentialheightsat500hPavariationsalsoshowsthattheindicationoftheformerinfluencingthelatterconfiguration,whichresultinhigherairtemperatureandlessprecipitationwhentheSSTAintheNorthAtlanticOceaninsummermotivatedEurasiancirculationofEApattern,furthertoinfluencethewet-dryvariationsinnorthwestChinabytheocean-to-atmosphereforcing.