CMIP5模式对春季北极涛动影响后期冬季ENSO不对称性的模拟能力分析

根据观测资料的研究指出春季北极涛动(Arctic Oscillation, AO)对随后冬季厄尔尼诺-南方涛动(El Nino–Southern Oscillation, ENSO)的影响具有明显不对称性。春季AO处于正位相时,它对随后冬季厄尔尼诺(El Nino)事件的影响显著,然而春季AO负位相对随后冬季拉尼娜(La Nina)的影响不明显。本研究分析了30个来自CMIP5的耦合模式对春季AO与随后冬季ENSO不对称性关系的模拟能力。30个CMIP5耦合模式中,只有CNRM-CM5和GISS-E2-H-CC模式能较好地抓住春季AO与冬季ENSO的联系。进一步分析这两个模式中春季AO与冬季ENSO的不对称性关系,发现CNRM-CM5模式能较好地再现春季AO与冬季ENSO的非对称关系,即春季AO正(负)位相会导致赤道中东太平洋出现El Nino(La Nina)型海表温度增暖(冷却)。然而,GISS-E2-H-CC模式的模拟结果显示,春季AO对随后冬季ENSO的影响是对称的。本文随后解释了CNRM-CM5(GISS-E2-H-CC)模式能(不能)模拟出春季AO与冬季ENSO不对称关系的原因。对于CNRMCM5模式,在春季AO正位相年,副热带西北太平洋上空存在明显的异常气旋和正降水异常,正降水异常通过Gill型大气响应对赤道西太平洋异常西风的形成和维持起着重要作用,异常西风通过激发向东传播的暖赤道Kelvin波对随后冬季El Nino事件的发生产生显著的影响;然而,在春季AO负位相年,副热带北太平洋的异常反气旋和负降水异常较弱,导致赤道西太平洋的异常东风不明显,因此,春季AO负异常对随后冬季La Nina的影响不显著。所以,CNRM-CM5模式能够较好地抓住春季AO对随后冬季ENSO事件的非对称性影响。相比之下,对于GISS-E2-H-CC模式,春季AO正(负)位相年副热带西北太平洋上存在显著的正(负)降水异常,通过Gill型大气响应在赤道西太平洋激发出明显的异常西(东)风从而影响随后冬季的El Nino(La Nina)事件。因此,在GISS-E2-H-CC模式中,春季AO对随后冬季ENSO具有对称性影响。另外,模式捕捉春季AO对随后冬季ENSO非对称性影响的能力与模式对春季AO空间结构的模拟能力有一定的联系。     

ENSO对印度洋偶极子非对称性的影响及机制研究北大核心

利用海表温度再分析资料、NCEP/NCAR大气环流再分析资料以及MPI-ESM1-2-LR气候模式PI-Control试验输出数据等,通过对不同强度的厄尔尼诺-南方涛动(El Nino-Southern Oscillation, ENSO)事件所对应的印度洋偶极子(Indian Ocean Dipole, IOD)事件的分析,探讨了ENSO对IOD偏度的调制作用。结果表明,伴随着赤道中东太平洋明显的正海温偏度,秋季印度洋海表温度存在西正东负的偏度。IOD与ENSO之间呈现出较强的非线性关系,且大部分强的正IOD事件对应着强El Nino事件。强El Nino位相下,IOD事件相关的海温与风场表现出很强的响应,强于La Nina事件产生的响应,表现为强的非对称性;相比较而言,弱El Nino事件与La Nina事件下引起的印度洋海温和风场的强度相当,并没有显著的非对称性。因此,ENSO可通过激发非对称的大气遥相关对IOD强度非对称性产生调制作用,印度洋海表温度偏度很大程度上是由强El Nino事件导致的强正IOD事件所贡献。     

太平洋年代际振荡冷、暖背景下ENSO循环的特征

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.     

ENSO循环与亚、澳季风和南、北方涛动的关系

文中从研究 ENSO循环的成因出发 ,分析了厄尔尼诺 ( El Nino)和拉尼娜 ( La Nina)的产生与西太平洋暖池地区西风异常的关系 ;在此基础上 ,探讨了西太平洋西风异常的形成和变化与亚洲和澳大利亚冬季风的关系 ;最后 ,分析了亚、澳冬季风的活动 ,西太平洋西风异常的形成和东传 ,以及厄尔尼诺和拉尼娜的交替出现等现象与南方涛动和北方涛动传播波的联系。     

中国冬季气温对ENSO的非线性响应特征

运用一双排套装的非线性神经网络统计模型,讨论了中国冬季气温对ENSO事件的非线性响应特征。结果表明,响应具有较明显的非线性特征,且这种非线性主要表现在振荡强度的差异上,即气温对El Nino事件的响应程度强于对La Nina事件的响应。El Nino位相下,气温的正距平中心主要出现在东北、江淮、福建以及新疆南部;La Nina位相下,上述地区气温出现负距平中心,但振荡强度较弱。气温对ENSO的响应可分为线性响应部分和非线性响应部分,其中非线性响应解释的方差约占线性响应的2/5,因此非线性响应的作用不可忽视。     

ENSO与中国夏季降水的联系:冬季QBO的调制作用

使用NCEP/NCAR再分析资料、中国气象局台站降水资料和GPCC降水资料,系统研究了在冬季平流层准两年振荡(Quasi-Biennial Oscillation, QBO)调制下,厄尔尼诺-南方涛动(El Ni?o-Southern Oscillation, ENSO)不同阶段与中国夏季降水的可能联系。根据两者的位相和强度,可将它们的配置分为QBO西风/El Ni?o、QBO西风/La Ni?a、QBO东风/El Ni?o、QBO东风/La Ni?a。研究结果表明,在年际时间尺度上,ENSO和QBO无显著相关关系。冬季QBO西风位相时,El Ni?o发展年夏季,我国整体偏旱,而华南偏涝;衰减年夏季,华南、华东北部偏旱,东北、长江流域偏涝。La Ni?a发展年夏季,我国东部降水异常呈负-正-负的三极分布;衰减年夏季,东南沿海偏涝。冬季QBO东风位相时,El Ni?o发展年夏季,长江以北偏旱;衰减年夏季,我国东部降水异常呈负-正-负的三极分布。La Ni?a发展年夏季,江淮和华南南部偏旱;衰减年夏季,我国东部沿海偏涝。ENSO是影响我国夏季降水异常的重要因子,而QBO的调制作用在ENSO衰减年夏季更为显著。相比冬季QBO东(西)风位相,QBO西(东)风位相时El Ni?o (La Ni?a)期间赤道西太平洋负(正)海温异常更强,衰减年夏季位于西太平洋的异常下沉(上升)运动和印度洋的异常上升(下沉)运动更强更深厚,西太平洋副热带高压范围更大(小),南亚高压更偏东(西)。      

华南冬季气温异常与ENSO的关系

利用1951一2012年华南192个测站逐月气温资料、NCEP/NCAR再分析月资料、NCC的ENSO监测资料,采用相关分析和合成分析等方法分析了华南冬季气温异常与ENSO的关系。结果表明:华南冬季气温对La Nina事件的响应比对E1 Nino事件显著,La Nina事件当年华南冬季气温以偏低为主,极强La Nina事件对应的华南冬季气温显著偏低,而中部型La Nina事件出现过华南冬季气温显著偏高的情况。当La Nina(El Nino)事件为东部型、Nino区海温异常的峰值月份出现在秋冬季,当年华南冬季气温易偏低(高)。从年际尺度上,当La Nina发生时,在对流层低层激发西太平洋异常气旋环流和北风异常,对应对流层中层北太平洋高压、乌拉尔山高压脊和东亚大槽南段均加强,西太平洋副热带高压减弱,东亚中高纬经向环流明显,冬季风偏强,导致我国大部分地区包括华南冬季气温偏冷,反之亦然。El Nino事件对华南冬季气温的影响具有年代际差异。对应华南冬季气温年代际变化的海温变化明显的区域位于北太平洋,而与ENSO关系不明显。     

热带太平洋SSTA与太平洋北美区500 hPa高度场的非线性关系

利用NOAA的逐月平均SST资料和NCEP/NCAR的逐月平均500 hPa高度场资料,采用非线性典型相关分析(NLCCA)分析了冬季热带太平洋SSTA场和太平洋北美地区500 hPa高度距平场之间的非线性关系,结论得出:NLCCA有能力表示出更一般的低维结构,可以提取资料集中传统CCA所不能提取的特征.NLCCA第一模态的典型相关变量μ从最大值变化到最小值,重建的SSTA场从强El Nino位相变换到强La Nina位相.La Nina位相的负距平中心(100 °W左右)比El Nino位相的正距平中心(150 °W左右)偏西约50个经度.对于500 hPa高度场,其非线性特征主要表现为定常波列(Rossby波)的位置偏差.El Nino时,PNA正位相的四个距平中心比La Nina时PNA负位相距平中心位置向东偏离约20个经度.NLCCA所得结论与合成分析结果一致.     

季节背景对ENSO循环过程中SSTA增/减幅作用的数值试验研究

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 Nino/La Nina事件均可存在 ,说明 El Nino/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 Nino/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     

热带太平洋风应力距平场的主振荡型分析

利用FSU（Florida State University）风应力逐月资料，运用POP方法，分析了热带太平洋地区风应力异常场结构与ENSO的联系。结果显示：纬向风应力有35、47和57月周期的传播型振荡；经向风应力有28和38月周期的传播型振荡。得到纬向、经向风应力传播型与ENSO振荡的耦合关系。同时指出，对El Nino／La Nina这样的大尺度海气相互作用现象的时空演变，应注重多种振荡混合的作用，而不应只分析单一模态的作用。风应力异常的局地振荡对El Nino／La Nina的影响也不应忽视。     

COMPARATIVE ANALYSIS OF VARIOUS DATA OF AIR–SEA TEMPERATURE DIFFERENCE AND ITS VARIATION ACROSS SOUTH CHINA SEA IN THE PAST 35 YEARS

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.     

Could the Recent Taal Volcano Eruption Trigger an El Ni?o and Lead to Eurasian Warming?

<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.     

VARIABILITY OF INTER-ANNUAL RELATIONSHIP BETWEEN INDIAN OCEAN DIPOLE AND HUAXI REGION’S AUTUMN PRECIPITATION

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.     

A COMPARATIVE ANALYSIS OF ATMOSPHERIC AND OCEANIC CONDITIONS BEFORE THE OCCURRENCE OF TWO TYPES OF EL NIO EVENTS

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.     

IMPACT OF ATMOSPHERIC LOW-FREQUENCY OSCILLATION ON THE IMMIGRATION OF NILAPARVATA LUGENS(STL) IN HUNAN AND JIANGXI PROVINCES

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.     

全球贸易隐含碳变化及其影响分析

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。     

Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings

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     

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;     

Information for Contributors

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.