与厄尔尼诺有关的北半球100hPa大气环流异常     

施能  曹鸿兴 《热带气象学报》1995,11(2):106-114

研究了北半球１００ｈＰａ冬季遥相关现象，指出，北半球冬季１００ｈＰａ存在ＰＮＡ流型，它的波列与５００ｈＰａ流型很接近，当厄尔尼诺发展到盛期（冬季）时，１００ｈＰａ出现强ＰＮＡ型，这种对应关系比５００ｈＰａ好些，此外，还研究了厄尔尼发生、发展各阶段的１００ｈＰａ低纬风场以及１００ｈＰａ春，夏，秋，冬四季平均环流异常特征，发现在厄尔尼诺发生年春季，１００ｈＰａ高度比反厄尔尼诺年大范围偏低，发生前的冬季  相似文献   

北半球冬季30hPa遥相关型特征及其与我国气候异常   总被引：2，自引：0，他引：2  

葛玲  假拉 《南京气象学院学报》1995,18(4):523-529

利用１９５７／１９５８￣１９９０／１９９１年共３４年冬季资料，采用一点相关法，研究了３０ｈＰａ１１￣２月各月平均高度场遥相关型及其强度指数的主要特征。分析了它们的天气动力学意义，并举例说明了他们与后期我国气候异常的联系。  相似文献   

亚洲夏季西风指数与中国夏季降水的关系   总被引：6，自引：4，他引：6  

刘飞  何金海  姜爱军 《南京气象学院学报》2006,29(4):517-525

对1958—2000年亚洲纬向风和我国160站夏季降水进行SVD分析,发现两者具有良好的耦合关系。根据分析结果定义了一个可以表征我国夏季降水的亚洲夏季西风指数(IASW)。西风指数高(低)年,长江中下游夏季降水偏少(多),华南、河套和东北地区降水偏多(少)。同时分析了高、低西风指数年的环流特征,发现当长江中下游夏季降水偏多而华南、河套和东北地区降水偏少时,500 hPa呈负EAP型,鄂霍茨克海和乌拉尔山有阻高建立,西太平洋副热带高压偏南,105°E越赤道气流偏弱,东亚夏季风偏弱,高纬的偏北气流和低纬的偏南气流在我国长江中下游地区汇合,梅雨锋加强,使得雨带在此维持。前期鄂霍茨克海区域平均位势高度以及前期1—3月西太平洋的热带对流活动可以作为预测夏季西风强弱的前兆信号。  相似文献   

Possible connection between anomalous activity of Scandinavian Atmospheric Teleconnection Pattern and winter snowfall in the Yangtze-Huaihe River Basin of China          下载免费PDF全文

ZHU Lin  CHEN Haishan 《大气和海洋科学快报》2019,(3):218-225

利用中国地面气候资料日值数据集(V3.0)逐日气象资料研究了我国江淮冬季降雪的时空变化及其与斯堪的纳维亚遥相关型(SCAND)的可能联系。结果表明:江淮冬季降雪表现出空间一致的年际变化,SCAND与江淮地区冬季降雪异常关系密切。江淮冬季降雪偏多通常对于SCAND正位相,500hPa阻塞高压、东亚大槽加强,有利于冷空气活动增强,江淮地区垂直运动增强,水汽输送增强;降雪偏少则对应SCAND负位相。研究结果有助于深入理解江淮冬季降雪异常的相关机理。  相似文献   

北太平洋海温分布与7月副高的遥相关分析   总被引：2，自引：0，他引：2  

李德萍  吴结晶  马艳 《海洋科学进展》2007,25(4):391-400

选取1952-2005年共54 a北太平洋月平均海表温度(SST)资料,奇异值分解结果表明,6月日界线附近西风漂流区的SST包含了北太平洋SST场的主要信息,西风漂流区与赤道冷水区的SST存在遥相关振荡,并且在6月振幅达全年最高值,11月其振幅出现次高值。分析结果表明,6月西风漂流区的SST可视为来年7月西太平洋副高强弱变化的信号:6月西风漂流区的SST偏低,则来年7月西太平洋副高偏强;反之,来年7月西太平洋副高偏弱。  相似文献   

前秋墨西哥湾流延伸区海温与东亚冬季风关系的年代际变化   总被引：1，自引：1，他引：0  

卢国阳  任保华  郑建秋  董祝雷  徐迪 《气象科学》2017,37(2):184-194

利用NCEP/NCAR再分析资料、哈德莱环流中心海表温度资料,研究了墨西哥湾流延伸区海温与东亚冬季风关系的年代际变化及可能原因。结果表明,秋季纽芬兰东南侧的墨西哥湾流延伸区海温与东亚冬季风联系在1970s中后期发生明显年代际突变,由1948—1976(P1)显著正相关变为1980—2012(P2)时段的不显著负相关。同时,与湾延区海温相联系的环流系统在P1和P2时段改变明显:P1时段湾延区海温偏高,冬季500 hPa位势高度场乌拉尔以东地区为大范围显著正异常,日本上空东亚大槽加深,东亚沿岸产生显著偏北风;而P2时段湾延区海温偏高,贝加尔湖上空为不显著负异常位势高度,东亚大槽区为弱的正异常,东亚沿岸有不显著偏南风异常。造成该突变的可能原因是P1时段湾延区海温偏高容易激发出北大西洋到东亚"正、负、正、负"的异常波列,且该异常中心与正位相欧亚遥相关(EU)波列的异常中心位置基本一致,位相叠加加强了正EU,进而造成东亚冬季风的异常强劲。而P2阶段从西欧到东亚沿岸呈现不显著的类似负位相EU波列,且异常中心与EU波列的异常中心位置有偏差,导致其与东亚冬季风关系相对于P1阶段发生了由显著正相关到不显著负相关的转变。  相似文献   

A Perspective on the Evolution of Atmospheric Blocking Theories: From Eddy-Mean flow Interaction to Nonlinear Multiscale Interaction     

Dehai LUO  Binhe LUO  Wenqi ZHANG 《大气科学进展》2023,40(4):553-569

In this paper, we first review the research advancements in blocking dynamics and highlight the merits and drawbacks of the previous theories of atmospheric blocking. Then, the dynamical mechanisms of atmospheric blocking are presented based on a nonlinear multi-scale interaction(NMI) model. Previous studies suggested that the eddy deformation(e.g., eddy straining, wave breaking, and eddy merging) might lead to the formation and maintenance of atmospheric blocking.However, the results were specu...  相似文献   

Indian Ocean SST modes and Their Impacts as Simulated in BCC_CSM1.1(m) and HadGEM3     

Bo LU  Hong-Li REN  Rosie EADE  Martin ANDREWS 《大气科学进展》2018,35(8):1035-1048

The sea surface temperature anomalies(SSTAs) in the tropical Indian Ocean(TIO) show two dominant modes at interannual time scales,referred to as the Indian Ocean basin mode(IOBM) and dipole mode(IOD).Recent studies have shown that the IOBM and IOD not only affect the local climate,but also induce remarkable influences in East Asia via teleconnections.In this study,we assess simulations of the IOBM and IOD,as well as their teleconnections,using the operational seasonal prediction models from the Met Office(Had GEM3) and Beijing Climate Center [BCC CSM1.1(m)].It is demonstrated that the spatial patterns and seasonal cycles are generally reproduced by the control simulations of BCC CSM1.1(m) and Had GEM3,although spectra biases exist.The relationship between the TIO SSTA and El Nio is successfully simulated by both models,including the persistent IOBM warming following El Nio and the IOD–El Nio interactions.BCC CSM1.1(m) and Had GEM3 are capable of simulating the observed local impact of the IOBM,such as the strengthening of the South Asian high.The influences of the IOBM on Yangtze River rainfall are also captured well by both models,although this teleconnection is slightly weaker in BCC CSM1.1(m) due to the underestimation of the northwestern Pacific subtropical high.The local effect of the IOD on East African rainfall is reproduced by both models.However,the remote control of the IOD on rainfall over southwestern China is not clear in either model.It is shown that the realistic simulations of TIO SST modes and their teleconnections give rise to the source of skillful seasonal predictions over China.  相似文献   

江淮流域持续性极端降水及预报方法研究进展   总被引：9，自引：4，他引：5       下载免费PDF全文

翟盘茂  李蕾  周佰铨  陈阳 《应用气象学报》2016,27(5):631-640

持续性极端降水过程会引发严重的洪涝灾害,是我国主要的灾害性天气之一,其形成机理和预报理论与方法研究受到广泛关注。近年来,针对持续性极端降水的形成机理和预报方法研究取得了一系列进展,主要包括:开展了我国区域性持续性极端降水事件的自动识别方法研究,研制建立了江淮流域持续性极端降水的大尺度环流概念模型,并提取了1~2周的前兆信号;从东亚—太平洋遥相关型 (EAP) 角度探究其对持续性极端降水的影响机理,并探讨利用EAP对江淮流域持续性极端降水进行预报的可行性。此外,在上述研究的基础上发展了基于关键影响系统的持续性极端降水的物理统计预报方法。  相似文献   

EFFECTS OF VARIATION OF WINTER SEA-ICE AREA IN KARA AND BARENTS SEAS ON EAST ASIA WINTER MONSOON   总被引：2，自引：0，他引：2  

武炳义  黄荣辉  高登义 《Acta Meteorologica Sinica》1999,(2)

By analyzing the observation data and performing the numerical simulation tests,it is shownthat the Kara and the Barents Sea area is a key region to influence climate variation over theNorthern Hemisphere.The variation of winter sea-ice area in the key region is closely associatedwith that of the EU teleconnection pattern at 500 hPa and East Asia winter monsoon(EAWM)intensity.When a heavy sea-ice prevails in the key region,the EU teleconnection pattern at 500hPa is excited easily(there are positive 500 hPa height anomalies over around Japan and WestEurope),and winter Siberia high is weakened,meanwhile,sea level pressure(SLP)has positiveanomalies over the Northern Pacific.Therefore,EAWM will be weakened,winter temperatureover East Asia is above normal and the frequency of cold-air activity in February in China will bedecreased.When the light sea-ice occurs in the key region,the results will be opposite.  相似文献