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1.
利用我国及美国国家气象局提供的热带太平洋月平均海温、水位、地球向外长波辐射和850hPa纬向风资料,对1980年以来的三次厄尔尼诺(El Ni(?)o)事件延长原因及其特征作一分析和探讨。文章指出,El Ni(?)o事件延长的原因主要是:在El Ni(?)o事件发生后,热带太平洋大气环流半年左右的韵律活动及在赤道南、北两侧明显的大气振荡加强,从而使大气的El Ni(?)o异常过程间隔半年相继发生。  相似文献   

2.
分析了1979—2018年两类厄尔尼诺事件期间月平均热带太平洋海面温度(sea surface temperature,SST)异常、对流降水异常、大气环流异常等特征,发现东部型、中部型厄尔尼诺期间海洋及大气加热场并不是赤道对称,赤道以南热源强度大于赤道以北。大气对热源的响应表现在:1)低层在大气热源西侧出现南、北半球热带相对应的气旋环流异常,但是赤道以南气旋的涡度大于赤道以北,且两类厄尔尼诺事件期间涡度中心的位置不同;到高层赤道中东太平洋呈现赤道对称的反气旋环流控制。2)低层热源的西侧出现西风异常,东侧为东风异常,西风异常的强度与范围明显大于东风异常,且东部型西风异常的强度大于中部型;而到高层,纬向风的风向和低层正好相反。3)低层东部型、中部型厄尔尼诺上升运动异常分别位于赤道中东太平洋和赤道中太平洋,下沉运动出现在热源东西两侧及赤道两侧5°N以北、5°S以南的热带地区;东部型到中层上升运动异常强度达到最大,而中部型到高层上升运动异常强度达到最大。4)低层东部型、中部型厄尔尼诺期间位势高度在中东太平洋为负异常,西太平洋为正异常;到高层,整个赤道中东太平洋地区均为位势高度正异常,并且在赤道两侧分别出现位势高度正异常中心,与反气旋环流涡度中心及下沉运动异常中心相对应。5)除西风异常范围大于东风异常,其他特征与赤道非对称热源GILL响应的理论计算模态基本一致。  相似文献   

3.
A class of El Nino atmospheric physics oscillation model is considered. The El Nino atmospheric physics oscillation is an abnormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conceptual oscillator model should consider the variations of both the eastern and westem Pacific anomaly patterns. An El Nino atmospheric physics model is proposed using a method for the variational iteration theory. Using the variational iteration method, the approximate expansions of the solution of corresponding problem are constructed. That is, firstly, introducing a set of functional and accounting their variationals, the Lagrange multiplicators are counted, and then the variational iteration is defined, finally, the approximate solution is obtained. From approximate expansions of the solution, the zonal sea surface temperature anomaly in the equatorial eastern Pacific and the thermocline depth anomaly of the seaair oscillation for El Nino atmospheric physics model can be analyzed. El Nino is a very complicated natural phenomenon. Hence basic models need to be reduced for the sea-air oscillator and are solved. The variational iteration is a simple and valid approximate method.  相似文献   

4.
根据水资源对厄尔尼诺事件的响应,得出了钱塘江流域水资源的统计预报模式:(1)在春季型厄尔尼诺事件的当年和夏季型厄尔尼诺事件的次年,金华站年径流量的距平一般都大于零:(2)厄尔尼诺事件的结束时间若超过5月1日,那么次年金华站年径流量的距平一般都大于零;(3)厄尔尼诺事件的强度越大。对钱塘江流域水资源的影响也越大。这对该流域长期及超长期的水资源预报具有重要的指示作用。  相似文献   

5.
-By using the sea surface temperature (SST) index of the Equatorial Pacific Ocean provided by Climate Analysis Center of U. S. A. , the numerical criteria of El Nino and La Nina events and their quantitative characteristics were calculated. Results show that the El Nino event was characterized with strong intensity, shorter life cycle and significant mature phase; however, the La Nina event has longer live cycle, weak intensity, insignificant mature phase. Through teleconnection analysis, it is found that the intensity index of SST over the Equatorial Pacific Ocean leads the intensity index of subtropical high by six months or so. During the El Nino years, the tropical cyclone over the northwestern Pacific is fewer than normal but stronger, and its genesis area shifts southeastward apparently; while in the La Nina years the number of tropical cyclones are larger.  相似文献   

6.
厄尔尼诺(El Ni(?)o)现象是海-气耦合系统异常变化的表现,其起因可能不是唯一的,行星运动对地球运动的影响可能会导致El Ni(?)o的发生。根据4个半世纪内El Ni(?)o发生的历史资料,分析其发生和行星运动的关系,得出的结论是:木星赤纬的变化和火星大冲与El Ni(?)o。的发生有显著的关系,表明这2颗行星的运动可能影响El Ni(?)o的发生。文中还根据分析结桌和El Ni(?)o混沌机制的观点,探讨了行星运动对海-气系统变化的影响机制。  相似文献   

7.
利用EOF分析方法,讨论了最近20a赤道太平洋次表层温度、纬向流距平与厄尔尼诺的关系.结果表明:赤道太平洋海温距平EOF分析第一、二主分量占总量的近80%,其中第一主分量类似于厄尔尼诺模态,第二主分量类似于暖池模态;后一模态存在着突变和渐变两种过程,其中由冷位相变暖位相过程为渐变过程,而暖位相变冷位相过程为突变过程.厄尔尼诺事件是赤道西太平洋暖池突变过程的结果.赤道太平洋纬向流距平EOF的第二主分量代表赤道西太平洋潜流和东太平洋南赤道流的变化,这个模态存在着半年左右的振荡和与厄尔尼诺同位相的年际振荡两种频率.另外,它还存在明显的年代际变化.赤道西太平洋潜流和东太平洋南赤道流减弱是产生厄尔尼诺的必要条件.统计回归分析表明,赤道太平洋海温距平和纬向流距平EOF的第二特征向量的时间系数对厄尔尼诺和拉尼娜均有一定的预报意义.  相似文献   

8.
用EOF分析方法对北太平洋及赤道太平洋地区1949~1979年31年海表面温度距平场进行分解,得到几个主要距平海温模态(EOF1~3),分析了EOF1~3的时空分布特征。得到海温距平场的EOF1和EOF2~3模态分别对E1—Nino事件和黑潮大弯曲有很显著的相关性,指出SST第三模态场对黑潮大弯曲的影响具有很好的持续性,持续时间为1~2年。最后讨论了相互的影响过程,为黑潮大弯曲和E1—Nino事件的预报的可能性提供了依据。  相似文献   

9.
In this paper,by using the ECMWF objective analysed data as well as CAC and NOAA grid point data of 1981 and 1983,the sensible and latent heat fluxes at the air and sea boundary surface within the range of 45°E-75°W, 35°N-35°S over the Pacific and the Indian Ocean are calculated. The purpose is to analyse the different revealing features during the mature stage and at the end of the 1982 -1983 El Nino event and to compare the difference of the features between thd El Nino and the normal. The result shows that the air and sea heat exchange west of the dateline over the central tropical Pacific during the EJ Nino period is more intense than that of the normal. However,the fluxes of the sensible and latent heat on the sea surface with strong warming of SSTneat by and on the south side of the equator east of 170°W are low and even negative,and the patterns of the sensible and latent heat fluxes over the Indian Ocean during the year of 1983 are similer to that of normal. Spatial patterns of the sensible  相似文献   

10.
王彰贵  刘克威  陈幸荣  谭晶  文岩 《海洋预报》2005,22(Z1):140-146
厄尔尼诺现象是目前发现的最明显气候异常信号.本文简短地介绍了厄尔尼诺的研究和预测现状,指出厄尔尼诺的预测水平还很低,其主要因素是一、没有建立起全球立体的厄尔尼诺监测网;二、研究局限于热带太平洋或热带印度洋-太平洋;三、缺乏多尺度相互作用的深入研究.另外,本文描述了厄尔尼诺发生前热带太平洋大气-海洋环流异常的几个特征.  相似文献   

11.
刘爱国  吴阳 《海洋通报》2003,22(4):87-91
ENSO事件是海—气相互作用的一种突出表现。它的出现会引发世界范围内的气候异常,从而导致台风活动的异常。根据1884—2000年的台风资料,采用统计的方法分析厄尔尼诺(暖事件)和反厄尔尼诺(冷事件)与登陆斗门—厓县热带气旋的关系得出:中等强度的冷、暖事件与登陆斗门—厓县热带气旋个数关系不明显:而在强或弱冷、暖事件中,冷事件影响年登陆斗门—厓县的热带气旋明显偏多。特别是在冷、暖事件影响下,登陆斗门—厓县热带气旋异常偏多年中,冷事件影响年占了64%。  相似文献   

12.
The relationship between SST in the Eastern Pacific and equatorial wind fields in the Western Pacific is analysed by using COADS.It is pointed out that in the year before El Nino , the continuative easterly anomalies and the meridional anomalies blowing from the Equator to both sides in the Equatorial Western Pacific cause the sea level in the Western Pacific to rise higher than in the Eastern Pacific and the sea level at the Equator to drop lower than on both sides of it. In the El Nino year, the westerly anomalies and the meridional anomalies blowing from both sides to the Equator bring warm water to build up around the Equator. At such times Kelvin waves are generated and they play an important role in raising SST in the Eastern Pacific. It is also emphatically pointed out that in the El Nino year the two maxima of the equatorial westerly anomalies, the two cross-equatorial air flows from the Northern Hemisphere to the Southern one and the two maxima of the near-equatorial tropical cyclones in the Eq  相似文献   

13.
-In this paper, monthly mean SST data in a large area are used. After the spacial average of the data is carried out and the secular monthly means are substracted, a time series (Jan. 1951-Dec. 1985) of SST anomalies of the cold tongue water area in the eastern tropical Pacific Ocean is obtained. On the basis of the time series, an autoregression model, a self-exciting threshold autoregression model and an open loop autoregression model are developed respectively. The interannual variations are simulated by means of those models. The simulation results show that all the three models have made very good hindcasting for the nine El Nino events since 1951. In order to test the reliability of the open loop threshold model, extrapolated forecast was made for the period of Jan. 1986-Feb. 1987. It can be seen from the forecasting that the model could forecast well the beginning and strengthening stages of the recent El Nino event (1986-1987). Correlation coefficients of the estimations to observations are resp  相似文献   

14.
Using the air-sea data set of January, 1983 (the mature phase of the 1982/83 El Nino event), the net radiation on the sea surface, the fluxes of the latent and the sensible heat from ocean to the atmosphere and the net heat gain of the sea surface are calculated over the Indian and the Pacific Oceans for the domain of 35°N-35°S and 45°E-75°W. The results indicate that the upward transfer of the latent and the sensible heat fluxes over the winter hemisphere is larger than that over the summer hemisphere. The sensible heat over the tropical mid Pacific in the Southern Hemisphere is transported from the atmosphere to the ocean, though its magnitude is rather small. The latent heat flux gained by the air over the eastern Pacific is less than the mean value of the normal year. The net radiation, on which the cloud amount has considerable impact, is essentially zonally distributed. Moreover, the sea surface temperature (SST) has a very good correlation with the net radiation, the region of warm SST coinci  相似文献   

15.
南海海温异常与ENSO的相关性   总被引:11,自引:0,他引:11  
使用1958-1987COADS资料,应用复经验正交函数(CEOF)分析方法,分析南海海表面温度场(SST)和风场(u及v)。结果发现,南海海温异常基本独立于西太平洋,同时存在类似于ENSO事件的年际变化,ENSO发生前冬季南海有异常降温过程,之后有增暖事件发生。分析还表明,南海SST异常主要取决于经向风场的异常强迫。南海SST与ENSO事件的相关性实质上反映了季风异常对ENSO循环的影响。  相似文献   

16.
-In this paper the variations of the sea surface temperature anomalies (SSTA) in the Equatorial Eastern Pacific are analysed. The results show that there are two peaks in the spectrum. One is the low frequency oscillation with a period of 3 - 5 years, and the other is the quasi-biennial oscillation. The former shows a westward migration in the warm episode of SSTA and the latter has the opposite trend. The El Nino events will be formed while the two frquency bands are in phase in the warming stage of SSTA in the Equatorial Eastern Pacific  相似文献   

17.
SouthernOscillationforcedbyheatsourceandtopographyQianWeihong,YouXintian(ReceivedJune5,1996,acceptedDecember9,1996)Abstract──...  相似文献   

18.
上升流是海洋中最重要的海洋现象之一,通过ROMS数值模型模拟并研究了2000—2013年间琼东上升流对ENSO信号(2002和2009年作为典型El Nio年; 2008和2010年作为典型La Nia年)的响应。结果表明,琼东上升流对ENSO气候事件有明显的响应。在El Nio信号较强时琼东上升流减弱,近岸海域水温升高;而在La Nia信号较强时琼东上升流加强,沿岸海域水温降低。对海面风场以及琼东海域沿岸流的分析表明,ENSO信号通过局地海面风场以及沿岸流对琼东上升流产生影响,并且风和沿岸流对琼东上升流的影响是协同的,在El Nio期间均不利于上升流的发展,而在La Nia期间二者的变化均有助于上升流的强化。  相似文献   

19.
1 IntroductionThe El Ni’o atmospheric physics oscillation is anabnormal phenomenon involved in the tropical Pacificocean- atmosphere interactions. Studies on the El Ni(ophenomenon are very attractive (Lin et al., 2000; Linet al., 2001, 2002; Wang, 2001; Feng et al., 2001;Feng et al., 2002; Liu et al., 2002; Wei and Chen,2003; Xie et al., 2002; Zhu et al., 2002; Pu et al.,2003; Gu et al., 2004; Yu and Liu, 2004). Lin and Mo(2004), Mo and Lin (2004) and Mo et al. (2004) alsostudied a s…  相似文献   

20.
本文对1985—1987年中国科学院“实验3”号考察船三个航次的赤道西太平洋考察资料的分析表明,海洋输向大气的热通量随季节变化不明显,各通量总的分布是西高东低。在1986—1987年厄尔尼诺影响下,海表水温较常年偏高,天气变化较历史上的厄尔尼诺年显著。  相似文献   

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