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1.
根据El Nino事件中正的海表面温度异常(sea surface temperature anomaly,简称SSTA)首先出现的区域及其传播特征,将El Nino事件分成3种类型,即东部型、西部型和驻波型.为了研究不同类型El Nino事件物理机制的差异,首先利用高分辨率全球海洋环流模式OPA9,对这3种不同类型的El Nino事件进行模拟.在逐月海表面风应力和热通量的驱动下,模式模拟出了1950-2005年问全球海温演变.模拟结果表明,模式可以很好地模拟出海洋的气候态,并且对El Nino事件期间的正SSTA首先出现的区域以及对正SSTA的传播特征都做出了很好的模拟,成功地模拟了不同El Nino事件的发展类型. 相似文献
2.
全球气候背景下厄尔尼诺对中国东部汛期降水的影响 总被引：8，自引：2，他引：8
对厄尔尼诺事件进行了定义，并详细讨论了不同气候背景下的厄尔尼诺过程对中国东部地区汛期降水的影响。分析发现：20世纪50年代以来共发生了14次厄尔尼诺事件；在70年代末、80年代初，赤道太平洋的海温有一个明显升高的趋势；不同气候背景下的厄尔尼诺过程中对中国东部汛期降水存在不同的影响，但是对长江中下游及江淮地区降水的影响是一致的，一般偏少。 相似文献
3.
1976—1977年及1982—1983年厄尔尼诺事件过程差异的年代际背景 总被引：11，自引：3，他引：8
本文根据NMC客观分析资料进行诊断分析,揭示了1976－77年及1982－83年这两次ElNino事件海气相互作用过程中的若干特征。结果表明：70年代末赤道西风异常背景场、SST背景场及其准4年周期振荡均存在年代际变化;SST背景场冷（暖）、80°W-0°E赤道区域850hPa纬向风异常西（东）风以及赤道太平洋SSTA准4年周期振荡东传型（西传型）共同决定了这两次事件的强度与类型的差异,即1976／77年事件为较弱的东部型EINino事件,而1982／83年事件表现为很强的西部型EINino事件。 相似文献
4.
Wang Shaowu 《Acta Meteorologica Sinica》1992,6(1):47-57
The El Nino events for 1870—1989 were identified according to the sea surface temperature(SST)over the easternequatorial Pacific(0—10°S,90—180°W)and Southern Oscillation Index.The chronicle of the El Nino events in histori-cal time(14708—1879)was reconstructed by using of a series of proxy data such as Australian droughts,Nile floods,Peruvian floods,numbers of landing typhoon in China,cool summers in East Asia,SOI calculated from tree ring data,and El Nino events identified mainly from meteorological and oceanographical conditions along the Ecuador and Perucoast.Finally,114 El Nino events were found for the period 1470—1989.The mean return interval was 4.5 years.The fre-quency of the events seems to have a cyclical variation of 70 years.No close relationship was found between the globalwarming and the frequency of El Nino events. 相似文献
5.
根据1951-2010年川西高原区7个气象站降水资料和气温资料以及60 a间发生的厄尔尼诺(El Ni?o)/拉尼娜(La Ni?a)事件,分析降水量、气温与El Ni?o /La Ni?a事件之间的关系,研究El Ni?o/La Ni?a事件对川西高原区气候的影响。结果表明：1951年以来川西高原区年降水量变化不大,呈现微弱的增加趋势,El Ni?o/La Ni?a 事件的发生对川西高原区年平均降水量有影响,El Ni?o事件影响下的年平均降水量减少,La Ni?a事件影响下的年平均降水量增加;El Ni?o年降水量低于正常年降水量39.14 mm,拉尼娜年降水量高于正常年降水量22.56 mm。1951年以来川西高原区年平均气温呈现微弱的波动上升趋势,川西高原区年平均气温与ENSO事件等级之间的相关性不显著。 相似文献
6.
利用全球海表温度(SST)资料、ONI(Oceanic Nino Index)序列以及中国160站逐月降水资料,研究了不同类型El Nino事件的主要特征及其对东亚大气环流及中国东部次年夏季逐月及季节降水的影响。结果表明:1)据El Nino事件期间SST最大正异常所在区域,将El Nino事件分为Nino3、Nino4和Nino3.4型。2)El Nino事件次年6月,Nino3型时降水显著正异常区主要位于鄱阳湖和洞庭湖流域,Nino4型时位于鄱阳湖流域、桂粤湘三省交界及广西西部,Nino3.4型时位于洞庭湖流域。7月Nino3型降水显著正异常区北移至长江流域,8月则呈西多东少反相分布。从次年6月至8月,Nino4型降水显著正异常区逐渐北移,Nino3.4型降水显著正异常区则从南到北再移向东北。3)在整个次年夏季,Nino3、Nino4和Nino3.4型降水显著正异常区在中国东部呈自南向北分布。无论逐月或季节降水,均是Nino4型降水正异常最强、Nino3.4型最弱。4)不同类型事件次年夏季和各月环流特征存在一定差异,总体而言,对于南亚高压,Nino3型、Nino4型事件后呈偏强、东伸和北抬的特点,且后者较前者时更强;Nino3.4型事件后主要呈减弱、西退特征。对于西太平洋副热带高压,Nino3型、Nino4型事件后主要呈偏强、西伸、北抬特征,后者较前者更强,西伸、北抬也更明显;Nino3.4型后,副高以东撤、北抬特征为主。 相似文献
7.
In recent years, El Nino Modoki (pseudo-El Nino) has been distinguished as a unique large-scale ocean warming phenomenon happening in the central tropical Pacific that is quite different from the traditional El Nino. Empirical Orthogonal Function (EOF) analysis is used to successfully separate El Nino and El Nino Modoki. The abilities of the NINO3 index, NINO3.4 index, NINO1+2 index and NINO4 index in characterizing the El Nino are explored in detail. It is suggested that the NINO3 index is comparatively optimal to monitor the El Nino among the four NINO indices, since other NINO indices either cannot well distinguish El Nino and El Nino Modoki signals or are easily disturbed by El Nino Modoki signals. Further, an improved El Nino Modoki index (IEMI) is introduced to better represent the El Nino Modoki that is captured by the second leading EOF mode of monthly tropical Pacific sea surface temperature anomalies (SSTA). The IEMI is an improvement of the El Nino Modoki index (EMI) through adjusting the inappropriate weight coefficients of the three boxes of EMI, and it effectively overcomes the lack of EMI in monitoring the two historical El Nino Modoki events and also avoids the possible risk of EMI in excluding the interference of El Nino signal, indicating the realistic and potential advantages. 相似文献
8.
In this study, we evaluate the fidelity of current climate models in simulating the two types of El Nino events using the pre-industrial output in CMIP3 archives. It is shown that a few climate models simulate the two types of El Nino events to some extent, while most of the models have serious systematic problems in simulating distinctive patterns of sea-surface temperature (SST) and precipitation anomaly associated with the two types of El Nino; that is, they tend to simulate a single type of El Nino. It is shown that the ability of climate models in simulating the two types of El Nino is related to the sensitivity of the atmospheric responses to the SST anomaly patterns. Models whose convective location is shifted to the east (west) as the SST anomaly center moves to the east (west) tends to simulate the two types of El Nino events successfully. On the other hand, models whose location of convective anomaly is confined over the western or central Pacific tends to simulate only the single type of El Nino event. It is also shown that the confinement of the convective anomaly over the western or central Pacific is closely linked to the dry bias and the associated cold bias over the eastern Pacific. That is, because positive El Nino SST anomalies over the eastern Pacific cannot increase local convection effectively when the total SSTs are still too cold due to a cold bias. This implies that the realistic simulation of climatology, especially over the equatorial eastern Pacific, is essential to the successful simulation of the two types of El Nino. 相似文献
9.
两类ENSO事件前期的热带太平洋海温距平场 总被引：7，自引：2，他引：7
分析了１９５６年以来两类ＥＮＳＯ事件热带太平洋海温距平场的特征。结果指出,东部型ＥｌＮｉｎｏ事件前期为ＬａＮｉｎａ事件年,热带中东太平洋为强的海温负距平,东部型ＬａＮｉｎａ事件前期为ＥｌＮｉｎｏ事件年,热带中不太平洋为强的海温正距平,中部型ＥｌＮｉｎｏ事件前期热带中西太平洋多为明显的海温正距平,中部型ＬａＮｉｎａ事件前期热带东太平洋多为明显的海渐负距平。两类ＥＮＳＯ事件前期海温距平场特殊基本相反。 相似文献
10.
热带太平洋地热散量与厄尼诺事件 总被引：3，自引：1，他引：3
国内外有关专家从海气间相互作用对厄尼诺事件进行了有益的探讨。认为与厄尼诺有关联的秘鲁海岸外的海面温度上升,是由于东南信风减弱而引起的冷水上翻的减弱(Bjerknes,1966;Wooster和Guillen,1974)。然而,E.M.Rasmusson等指出,日界线以东(140—170°w)沿着赤道,风距平出现的东西减弱不是在厄瓜多尔—秘鲁沿岸海温正距平之前,而是在它之后。C.S.Ramage等通过统计,在单侧检验15％的水平上没有拒绝海面温度与风速无关的零假设。认为人们必须抛弃厄尼诺时期秘鲁海面的风异常弱的想法。 相似文献
11.
厄尔尼诺事件与登陆我国热带气旋关系的初步分析 总被引：2，自引：1，他引：2
本文用统计学方法对厄尔尼诺事件(包括反厄尔尼诺事件,下同)与登陆我国热带气旋之间的关系作了初步分析。结果表明,厄尔尼诺年当年登陆我国的热带气旋较常年偏少,登陆纬度偏南,其中的台风登陆频数亦较常年偏少;而反厄尔尼诺年当年则相反。分析还表明,上述影响的可能机理是,厄尔尼诺事件发生时异常海温影响沃克环流、哈得来环流及副高脊线位置的结果。 相似文献
12.
利用我国近500年旱涝等级资料和公元1500年以来的El Nino事件的记录，用合成分析方法，讨论El Nino事件的有关年份，中国东部夏季降水的空间分析特征。对1500—1990年间101例El Nino事件所作的El Nino当年的旱涝等级合成图表明:多雨地带在东北、黄淮地区和广东沿海，而干旱少雨地带在内蒙—甘肃和长江中下游地区；这101例El Nino事件结束后的第一个非El Nino年的合成图，则表明其旱涝分布型几乎正好与El Nino当年的相反。1951—1990年间的9例El Nino事件当年 相似文献
13.
厄尔尼诺和反厄尔尼诺事件与西北太平洋台风活动 总被引：42，自引：12，他引：42
用统计相关和典型年合成方法分析了厄尔尼诺和反厄尔尼诺事件与西北太平洋台风活动的关系，指出厄尔尼诺年台风活动减少，反厄尔尼诺年台风活动增加，而且台风活动与厄尔尼诺、反厄尔尼诺事件起始和终止时间、强度、台风生成区域有关。利用厄尔尼诺和反厄尔尼诺年台风活动频数的统计特征，及台风频数与海温等要素的时滞相关关系，为台风频数的预测提供了有益的信息。还应用奇异值分解方法，分析了高度场和海温场的相关关系。结果表明，厄尔尼诺年海气耦合作用将造成不利于台风发展的环流条件，因此台风偏少，反厄尔尼诺年则出现相反的情况。 相似文献
14.
热带大气季节内振荡激发El Nino的机制 总被引：15，自引：1，他引：15
资料分析了表明,热带大气季节内振荡同Ｅｌ Ｎｉｎｏ发生有密切的关系。在Ｅｌ Ｎｉｎｏ事件发生之前,热带大气（尤其是赤道西太平洋地区）季节内振荡异常加强;伴随着Ｅｌ Ｎｉｎｏ的发生,热带大气季节内振荡动能明显增加。简单海－气耦合模式的分析表明,只有在年陵时间尺度大气外强迫作用下,海－气系统才可以产生类似ＥＮＳＯ模的耦合波。资料和理论模式分析和结果相结合,说明热带大气季节内振荡激发Ｅｌ Ｎｉｎｏ的机制 相似文献
15.
Numerical simulations of anomalies of precipitation and surface air temperature in china in the summer of 1997 总被引：1，自引：0，他引：1
1.IntroductionStatisticalstudiesdemonstratedthatinEINinoyearstheprecipitationinsummerintheChangjiangRiverandHuaiheRiverBasinsisprobablyabovethenormalwhileitispossiblybelowthenormalinthenorthernChinaandtheHetao(theGreatBendoftheHuangheRiver)region.ThetemperatureinsummerisusuallylowerthannormalinEastAsia,especiallyinNortheastChina.Therewere6yearswithseverelowtemperaturesince1951,andtheyare1954,1957,1964,1972,1976and1983,whichareallrelatedtotheEINinoyears(seeHuangetal.,1989,1992;Xiangand… 相似文献
16.
Distinguished Effects of Interannual Salinity Variability on the Development of the Central-Pacific El Nino Events 
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下载免费PDF全文 El Nio events in the central equatorial Pacific (CP) are gaining increased attention,due to their increasing intensity within the global warming context.Various physical processes have been identified in the climate system that can be responsible for the modulation of El Nio,especially the effects of interannual salinity variability.In this work,a comprehensive data analysis is performed to illustrate the effects of interannual salinity variability using surface and subsurface salinity fields from the Met Office ENSEMBLES (EN3) quality controlled ocean dataset.It is demonstrated that during the developing phase of an El Nio event,a negative sea surface salinity (SSS) anomaly in the western-central basin acts to freshen the mixed layer (ML),decrease oceanic density in the upper ocean,and stabilize the upper layers.These related oceanic processes tend to reduce the vertical mixing and entrainment of subsurface water at the base of the ML,which further enhances the warm sea surface temperature (SST) anomalies associated with the El Nio event.However,the effects of interannually variable salinity are much more significant during the CP-El Nio than during the eastern Pacific (EP) El Nio,indicating that the salinity effect might be an important contributor to the development of CP-El Nio events. 相似文献
17.
Implication of the South China Sea Throughflow for the Interannual Variability of the Regional Upper-Ocean Heat Content 总被引：2，自引：0，他引：2
In this study the interannual variability of the upper-ocean heat content in the South China Sea (SCS) was revisited using simple ocean data assimilation (SODA) combined with objective analyzed data sets that included the horizontal and vertical structures.The results confirmed that the upper-ocean heat content in the SCS is lower than normal during the mature phase of El Nin o events,and two super El Nin o events,1982/1983 and 1997/1998 were also included.The variability of the heat content was consistent with the variability of the dynamic height anomalies.The SCS throughflow (SCSTF) plays an important role in regulating the interannual variability of the heat content,especially during the mature phase of El Nin o events. 相似文献
18.
流感爆发与气候的剧烈变化有关。本文揭示了拉马德雷冷位相、拉尼娜、太阳黑子极值年、厄尔尼诺、低温冷害、沙尘暴、潮汐南北震荡异常与流行性感冒世界大流行相互对应的关系及其物理机制,对气候及其相关灾害的预测有重大科学意义。规律表明,在拉马德雷冷位相时期,全球强震、低温、飓风伴随拉尼娜、全球性流感伴随厄尔尼诺将越来越强烈。面对日益增大的全球灾害,长期气候预报意义重大。 相似文献
19.
El Nino as well as the Southern Oscillation is one of the strongest signals known so far over climatic noise ininterannual variations of the atmosphere and oceans.A great number of studies have shown definitely relationships be-tween the events and climatic anomalies in China.In this review,observational results obtained in the recent severalyears are first summarized.Then the possible physical mechanisms on the influence of El Nino are presented and,finally,the associated problems are discussed. 相似文献
20.
地球自转减慢与厄·尼诺现象的形成 总被引：9，自引：0，他引：9
著名的厄·尼诺现象的成因,目前尚无一致的结论。本文得到,地球自转大幅度持续减慢与厄·尼诺现象的发生,两者有相当一致的同步演变关系。并且,后者比前者平均滞后14天,南方涛动也比地球自转减慢滞后。表明地球自转急剧减慢很可能是形成厄·尼诺现象的一个重要原因。文中还从固体地球、大气、海洋三者总角动量守恒的假定出发,讨论了地球自转减慢影响赤道洋流、信风减弱的量级及其形成厄·尼诺的物理途径。 相似文献