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1.
在以赤道低平流层纬向风垂直切变为依据划分平流层QBO位相的基础上,讨论了赤道低平流层纬向风QBO与对流层环流及东亚季风的关系.结果表明强冬季风和弱夏季风对应着赤道低平流层纬向风的东风切变位相,强夏季风和弱冬季风对应着赤道低平流层西风切变位相,赤道低平流层纬向风QBO对对流层环流有一定影响,冬春季节平流层与对流层的相互作用比夏秋季节明显.  相似文献   

2.
赤道平流层QBO与我国7月雨型的关联   总被引:12,自引:2,他引:12       下载免费PDF全文
根据1953~1991年赤道平流层纬向风资料分析,得出我国东部地区7月份主要雨带位置与赤道平流层30~50 hPa平均纬向风准两年振荡(以下简称赤道平流层QBO)有较好的关联。在西风位相条件下,我国7月主要雨带位置较偏北;在东风位相条件下,我国7月主要雨带位置易偏南。它们之间的关系主要是通过对对流层环流的影响相联系的。利用赤道平流层纬向风的变化规律并结合冬季北太平洋对流层环流特征,对我国7月主要雨带类型的预报,有一定实用意义。  相似文献   

3.
热带准两年振荡影响北半球冬季大气环流的诊断分析   总被引:11,自引:3,他引:8  
陈文  杨蕾  黄荣辉  邱启鸿 《大气科学》2004,28(2):161-173
利用NCEP/NCAR再分析资料,首先讨论了热带纬向风准两年振荡(QBO)的东、西风位相的划分标准.结果发现,赤道50 hPa的风与西风深厚度关系最密切,即赤道50 hPa的纬向平均风为西(东)风时往往代表平流层下层为一层深厚的西(东)风.在此基础上诊断分析了1958/1959~1997/1998年共40个冬季中热带纬向风QBO对北半球中高纬度地区纬向平均环流和准定常行星波传播的影响.诊断分析表明,热带QBO对北半球冬季大气环流的影响主要表现在平流层和对流层上层.热带QBO的东风位相年与西风位相年相比,中高纬地区的绕极西风环流明显减弱,中低纬地区则出现相反变化,从而在平流层的纬向平均环流分布上呈现偶极子形式.纬向平均流的这种年际变化可以很好地用中高纬度准定常行星波传播的异常加以解释,QBO的东风位相年和西风位相年相比,中高纬准定常行星波向极地的传播更强,从而在高纬度平流层产生异常的E-P通量辐合,波-流相互作用的结果使得西风减弱.但是热带纬向风QBO的影响在1958/1959~1997/1998年的前后20年有所差异.后20年相对于前20年而言,东西风位相的差异有所减小,Hol-ton-Tan振荡明显减弱;就行星波传播而言,东风位相年下,前20年行星波向上传播较弱,而后20年则以大约70°N为分界点,以南向上传播较强,以北向上传播较弱.这种差异可能跟中高纬度纬向西风的自身变化有关.  相似文献   

4.
赤道低平流层纬向风垂直切变与ENSO变率的关系   总被引:1,自引:0,他引:1  
利用NCEP/NCAR 40a再分析资料研究了赤道低平流层纬向风垂直切变与ENSO变率间的关系。结果得出,赤道低平流层纬向风的垂直切变呈现明显的准两年振荡,SOI和Nino3区SSTA的准两年周期成分与赤道低平流层纬向风垂直切变分别呈现反位相和同位相关系。赤道低平流层西(东)风切变位相时,OLR、1000hPa高度,2000hPa高度和温度、850hPa温度等要素的距平分布与其在El Nino(La Nina)时段的分布相似。  相似文献   

5.
西太平洋副高活动与平流层QBO关系的研究   总被引:10,自引:1,他引:10       下载免费PDF全文
李崇银  龙振夏 《大气科学》1997,21(6):670-678
资料分析表明,西太平洋副高活动有准两年振荡特征,副高的相对强度和副高脊线的纬度位置都清楚地表现出这种振荡。而且分析还表明,平流层低层纬向风的垂直切变同西太平洋副高活动有关,东(西)风切变对应着脊线位置偏北的较强(弱)副高形势。平流层低层东(西)垂直切变在赤道对流层上部所引起的异常上升(下沉)运动,导致Hadley环流的异常加强(减弱)可能是平流层QBO影响西太平洋副高准两年振荡的重要机制。用IAP-GCM所作的数值模拟试验得到了同观测资料分析相一致的结果。  相似文献   

6.
亚澳季风异常与ENSO准四年变化的联系分析   总被引:2,自引:0,他引:2  
分析了赤道地区纬向风的年际变化特征,以及亚澳季风与ENSO在各个位相的联系。结果表明:赤道纬向风变化与中东太平洋海温变化在准四年周期上是强烈耦合的;在El Eino期间东亚冬季风弱,夏季风强,而南亚夏季风弱,反之,在La Nina期间东亚冬季风强,夏季风弱,而南亚夏季风强;东亚地区的异常北风有利于西太平洋西风异常爆发,使得东太平洋海温升高,但只有随后在中东太平洋出现持续性西风异常,El Nino才能发展,其中来自太平洋中部的异常北风(并不是来自东亚大陆地区)和南太平洋中部的异常南风的辐合对中东太平洋出现持续性西风异常起重要的作用,尤其是澳大利亚东北部的季风异常的影响更为显。  相似文献   

7.
北半球平流层环流与亚洲夏季风关系的初步分析   总被引:3,自引:1,他引:3  
刘晓东  瞿章 《气象学报》1991,49(2):244-248
季风是大气环流季节变化的某些特性在局部地区的特殊表现。人们逐渐认识到,大气环流的季节变化是全球性的现象。但长期以来关于季风的研究一般只限于对流层。而对流层与平流层大气之间存在着一定的联系,平流层的季节变化往往早于对流层。本文对本世纪70年代亚洲夏季风强年和弱年的平流层环流及其季节变化作了对比分析,指出:亚洲夏季风强弱与平流层环流有密切联系。弱季风年前冬(11—4月)50 hPa绕极地的西风环流偏强,季节变化开始得晚,但完成得早。50与  相似文献   

8.
利用Atuona Marquesas Is站对流层最大西风层和最大东风层纬向风异常值的差值,构造了赤道中,东太平洋Walker环流强度指数Id。,并对Id平流层下部QBO西风位相的长度和起始季节与ENSO事件的联系进行了研究。  相似文献   

9.
陈文  黄荣辉 《大气科学》1996,20(5):513-523
本文构造了一个34层球坐标原始方程波-流相互耦合谱模式,利用此模式从拉格朗日平均环流的观点研究了在常定流下行星波对臭氧的输运作用。研究结果表明,行星波对臭氧的输运有明显的季节变化,在北半球冬季,由于行星波上传到平流层而大大增强了中高纬地区向极地向下的O3输运;并且还表明,热带纬向风的QBO不仅通过影响东、西风切变而引起热带O3分布的年际变化,而且通过影响行星波的传播引起了行星波对O3输运的年际变化,这表现为当热带纬向风处于东风位相时,中高纬地区行星波对O3的输运比西风位相时强  相似文献   

10.
用NCEP/NCAR再分析月平均风、压场资料得到1958—1997年5—10月月际场的局地型相似系数(LPAC)。多年平均LPAC表明了对流层和平流层低层印度夏季风环流的建立、东亚夏季风环流的北进和南亚高压上高原的过程,这些区域LPAC值较同纬度非季风区明显偏低。在平流层中层,夏季型环流表现出纬向对称性和由高纬向低纬的传播特征。对东亚LPAC气候变率时空剖面及3个涝年LPAC异常的分析反映出环流型季节转变异常及其与东亚月降水异常的关系。  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
<正>The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth’s climate and environment.  相似文献   

13.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

14.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

18.
19.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

20.
正Journal of Meteorological Research is an international academic journal in atmospheric sciences edited and published by Acta Meteorologica Sinica Press,sponsored by the Chinese Meteorological Society.It has been acting as a bridge of academic exchange between Chinese and foreign meteorologists and aiming at introduction of the current advancements in atmospheric sciences in China.The journal columns include Articles.Note and Correspondence,and research letters.Contributions from all over the world are welcome.  相似文献   

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