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1.
为了分析ElNio事件发生和消亡中热带太平洋纬向风应力的动力作用，建立一个类似于Zebiak的简单热带海洋数值模式，在观测到的风应力异常的强迫下，模拟赤道太平洋地区1971年1月至1998年8月海表温度异常的变化。结果表明，模式对观测的Nio3区海表温度异常(SSTA)有很好的模拟能力。模拟和观测Nio3区SSTA之间的相关系数可达0.90。模式对ElNio事件期间赤道太平洋海表温度异常随时间变化也有较好的模拟能力。为了分析ElNio期间SSTA的空间分布及其随时间变化的动力学机制，还对19861989年ENSO循环期间赤道太平洋地区观测的SSTA的传播特征及其形成机制进行了分析。模式较好地模拟出了观测到的赤道太平洋地区SSTA的传播特征，即从1986年底至1987年4月，SSTA具有向东传播的特征，从1987年6月至1988年2月具有向西传播的特征。动力学分析的结果表明，赤道中西太平洋地区的纬向风应力异常对ElNio事件的发生和消亡具有重要作用。赤道中西太平洋地区的西风异常可强迫出东传的Kelvin波，这个东传的Kelvin波对正SSTA的东传起主要作用，当这个东传的Kelvin波到达东边界，由于东边界的反射作用，在东边界产生西传的Rossby波，这个西传的Rossby波对赤道中东太平洋地区正SSTA的西传起主要作用。东传Kelvin波和反射的Rossby波对ElNio期间赤道东太平洋正SSTA二次峰值的形成具有重要作用。 相似文献
2.
本文基于以925 hPa NCEP/NCAR再分析风应力距平为初始强迫场的Zebiak-Cane海气耦合模式对1997/1998 El Nio事件集合预报平均结果,对1997/1998 El Nio事件进行热力学诊断分析.结果表明:(1)在整个El Nio事件过程中,在赤道太平洋从西到东的各个Nio区中,平流作用主要起促进作用,而热力阻尼项则基本为衰减或抑止作用.(2)从Nio 4区到Nio 1 2区,纬向平流对SSTA上升的促进强度变化不大,而经向平流和垂直上升流对SSTA增加的促进作用在逐渐增强.同时,热力阻尼项对SSTA变化的抑制作用也呈依次增强.(3)平流项中,经向平流的贡献相对显著. 相似文献
3.
太平洋年代际振荡冷、暖背景下ENSO循环的特征 总被引：12，自引：1，他引：11
利用英国气象局哈德莱中心的月平均海温距平资料、美国Scripps海洋研究所联合环境分析中心(JEDAC)的海表和次表层海温观测资料以及NCEP/NCAR再分析资料,研究了太平洋年代际振荡(PDO)不同背景下ENSO循环的特征.结果表明,PDO为ENSO循环提供了一个年代际气候背景,在PDO的暖位相时期,El Nino事件发生的频率较高,强度较强;反之,在PDO的冷位相时期,La Nina事件发生的频率较高,强度较强.而且在不同的太平洋年代际振荡背景下,ENSO循环表现出不同的特征.在PDO冷位相时期,发生El Nino(La Nina)事件时,正(负)的SOTA从西太平洋沿温跃层向东传播,正(负)的SSTA从赤道东太平洋向西扩展到中太平洋,ENSO事件先在赤道东太平洋爆发.在PDO的暖位相时期,发生El Nino(La Nina)事件时,正(负)的SOTA首先出现在赤道中太平洋,然后沿温跃层向东传播,正(负)的SSTA从赤道中太平洋向东扩展到东太平洋,ENSO事件首先在中太平洋爆发.这为ENSO预测提供了新的线索. 相似文献
4.
一种新的ENSO循环负反馈机制 总被引：5，自引：0，他引：5
本文利用包含海洋表面边界层和大气辐合反馈过程的热带太平洋海气耦合异常模式的30年模拟结果，通过对模式ENSO循环演变特征和正负反馈机制的细致分析揭示出了ENSO循环形成的一种新的负反馈过程。指出:ENSO循环的正反馈机制是不稳定海气相互作用过程，且这一不稳定过程的发展在暖态中明显强于冷态；ENSO循环的负反馈机制在冷暖态中表现不同，在冷态消亡过程中，这种负反馈过程主要表现为暖的西传Rossby波经西边界反射产生的暖的东传Kelvin波来抑制冷位相不稳定发展的，但在暖态消亡过程中，不存在类似的纬向波作用过程，其负反馈过程主要表现为在海气耦合不稳定充分发展时伴随的赤道两侧冷水上翻过程的加强以及非线性过程的衰减作用共同抑制了不稳定的发展，并最终使系统从暖态恢复至冷态。本文得出的ENSO循环暖位相中的负反馈机制和近年来国外提出的“时滞振子”理论明显不同。 相似文献
5.
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
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7.
利用热带太平洋地区 2层区域海洋模式和再分析资料探讨了大气 /海洋的季节背景对ENSO时间尺度上海温异常的增幅或减幅作用。结果表明 :不论什么季节背景下 ,就海洋变化而言 ,El Nino/La Nina事件均可存在 ,说明 El Nino/La Nina事件的存在和维持并没有季节性选择 ;模式海洋的西太平洋赤道地区次表层海水温度异常变化位相明显超前于东太平洋SSTA且在空间上自西向东传播 ,同时有位相超前的量还包括模式第 1层厚度异常及热容量异常 ,这些对 ENSO的预测和机制研究具有重要意义。 SSTA的振幅在不同的季节背景下可受到不同的调节。以春季为背景 ,同样的异常风应力作用于海洋 ,可使 NINO3区 SSTA较正常季节背景下该区的 SSTA振幅明显增大 ;而在冬季背景下可使 SSTA受到一定程度的减幅 ,这说明 El Nino/L a Nina现象的发生和消亡有季节选择倾向。与春季背景下 NINO 3区SSTA的增幅倾向相反 ,模式第 1层厚度异常的振幅则受到削弱。而西太平洋赤道地区 ,模式海洋混合层的厚度异常则有所增强。这种与 SSTA增 /减幅反相关的现象需要进一步研究 相似文献
8.
通过对ENSO循环的两个不同位相中印度洋地区海表温度变化特征的分析,指出印度洋地区的海温变化与赤道东太平洋地区的海温变化有较好的相关关系,是ENSO循环的重要组成部分。对应于赤道东太平洋暖位相期,印度洋地区的海温分布为东冷西暖;与此相反,在赤道东太平洋冷位相期,印度洋地区的海温分布为东暖西冷。进-步的分析还发现,印度洋东、西部地区海温变化纬向差异最明显的区域位于印度洋赤道以南0～25°S附近,且这种差异具有明显的年季变化特征,在整个夏季风期间差异较大,而冬季风期间较小,其中冷位相期间的纬向差异比暖位相期间的纬向差异大。代表印度洋纬向差异的IDM(偶极指数)变化与赤道东太平洋地区的海温变化有很好的正相关关系。 相似文献
9.
简单海气耦合模式大气运动方程的非线性对ENSO循环模拟的影响 总被引：1，自引：1，他引：0
研究简单海气耦合模式大气运动方程非线性对ENSO循环的影响,即讨论大气运动方程的纬向非线性、经向非线性、纬向和经向非线性对ENSO循环的影响。同时,讨论了ENSO循环对大气运动方程非线性的敏感性问题。数值实验证明,大气运动方程的非线性对ENSO循环的影响明显,并且ENSO循环对大气运动方程的非线性非常敏感。因此,研究简单海气耦合模式中大气运动方程的非线性对ENSO循环的影响,对进一步理解ENSO循环的物理机制,具有一定的理论意义和实用价值。 相似文献
10.
在所构造的海气耦合模式中,采用Zebiak海洋模式框架,并重建了一个海洋数值模式,大气模式采用了Gill模式.在大气模式中保留了时间发展项,潜热加热采用了Kleeman方案.对模式的积分结果表明,海温异常具有3～7年的准周期振荡.在模式El Nino事件的初始阶段,西风异常,海温正距平(SSTA)首先在赤道西太平洋发生,然后向东传播、加强.在模式ENSO循环的位相转换过程中,SSTA的空间分布共有4种不同类型.模式模拟的El Nino事件的初始阶段有两种发展类型,它们是:在初始阶段中西太平洋和东太平洋沿岸各有海表温度的正异常发生.在以后的发展中,一种情况是这两块正SSTA都发展连成一片,形成El Nino事件;另一种情况是中西太平洋地区的正SSTA衰减,中东太平洋地区的正SSTA加强,向西传播,形成El Nino事件.模式模拟的La Nina事件的初始阶段也有两科发展类型,它们的发展过程和El Nino事件初始阶段的发展过程相似. 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 Nio3.4 index in summer and autumn but negatively correlated in spring and winter. 相似文献
12.
Fei LIU Chen XING Jinbao LI Bin WANG Jing CHAI Chaochao GAO Gang HUANG Jian LIU Deliang CHEN 《大气科学进展》2020,37(7):663-670
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(Stl), 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.
Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings 
下载免费PDF全文
下载免费PDF全文 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
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《大气科学进展》2014,(6)
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.
《Acta Meteorologica Sinica》2014,(6)
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