冬季北极涛动异常对北太平洋风暴轴的可能影响

基于美国国家海洋和大气局气候预测中心公报的北极涛动（Arctic Oscillation,AO）指数逐月数据以及美国国家环境预报中心和大气研究中心的1986—2017年逐日再分析资料等,运用回归和合成分析等方法,分析了北极涛动与北太平洋地区风暴轴的时间演变特征、两者之间的联系及AO异常影响风暴轴的可能机制。结果表明：1）风暴轴经度指数与纬度指数有显著正相关性,两者具有同步变化的特征,而这两者与风暴轴强度指数都呈负相关,但不显著。AO指数与北太平洋风暴轴强度呈显著正相关,且AO指数与风暴轴经度、纬度指数也呈正相关,但并不显著。2）在北极涛动强正（负）位相年份,风暴轴区域天气尺度滤波方差强（弱）、500 hPa高度场上东亚大槽减弱（加深）、急流偏北偏强（偏南偏弱）、扰动动能增强（减弱）、斜压性增强（减弱）。可能影响机制是,异常变化的AO影响东亚大槽,改变急流强度,使斜压性发生变化,进而对风暴轴产生影响。     

冬季北太平洋风暴轴指数的评估及其改进

首先对风暴轴的定义及其强度和位置表征方法进行了归纳总结, 然后利用1958～2001年44年冬季ERA40位势高度场资料重新评估了几种不同的风暴轴特征指数, 分析得到: 这些不同的定义方法在表征风暴轴强度变化方面具有一致性, 但在描述风暴轴的位置变动方面有较大差异。根据冬季北太平洋风暴轴主体的强度和位置变化特征, 提出了一组更为恰当的动态定量的表征方法, 即取北太平洋及其周边区域 (30°N～60°N, 120°E～120°W) 冬季500 hPa位势高度天气尺度滤波方差大于20 dagpm2的所有格点滤波方差的平均值, 以及满足上述条件所有格点的经度平均和纬度平均分别作为冬季北太平洋风暴轴的强度指数 (NII)、经度指数 (NXI) 和纬度指数 (NYI)。通过比较分析, 证明了新定义的指数更能反映风暴轴实际的变动特征。继而利用新指数分析了冬季北太平洋风暴轴的强度和位置的长期变化, 得到以下结论:44年中, 冬季北太平洋风暴轴的强度微弱增加, 且在1970年代中期以前北太平洋风暴轴的强度和位置的年代际变化关系复杂; 1970年代中期以后北太平洋风暴轴的强度和位置的年代际变化具有准协同一致性, 表现为偏弱期位置偏西偏南, 偏强期位置偏东偏北。而且, 这种长期变化与太平洋海气系统成员的低频变化有相关性, 其变化成因是复杂的。     

冬季北太平洋风暴轴的年代际变化

对1948-2004 NCEP／NCAR 500hPa高度场资料进行滤波后,采用累积距平、Morlet小波分析、合成分析等方法,研究了风暴轴中心的强度、经纬度以及面积指数的年代际变化。结果表明,56a来北太平洋风暴轴的中心强度平均约为32dagpm^2,中心位置约在172°W、44．5°N。小波分析表明,冬季北太平洋风暴轴的中心强度和面积都存在着18a的年代际变化周期。此外,风暴轴中心强度与面积指数有很好的正相关关系。总的来说,风暴轴中心强度增强（减弱）时期,一般对应着风暴轴面积增大（缩小）和位置向西（东）、向南（北）移动。     

资料

资料１９９７年７月５００ｈＰａ环流指数、环流特征量资料国家气候中心气候预测室环流指数西太平洋副热带高压东亚槽极涡月平均候平均１２３４５６面积指数强度指数西伸脊点脊线位置北界位置平均位置平均强度中心位置经度纬度强度亚欧ＩＺ７７７３９０７０５７９７７３地...     

冬季北太平洋风暴轴异常及其与东亚大气环流的关系

利用NCEP/NCAR逐日再分析资料,应用滤波方差、相关分析、合成分析等研究了1963年冬季至2011年冬季北太平洋风暴轴的时空演变特征,并探讨了风暴轴活动强弱与东亚—北太平洋大气环流的关系。结果表明：与1980s后期风暴轴活动显著增强相比,近10 a来风暴轴活动又进入较气候平均水平偏低的阶段,且风暴轴主体位置有着向东北、西南两侧的振荡现象。风暴轴活动强（弱）年,东亚地区近地面温度偏高（低）、对流层低层阿留申低压和西伯利亚高压偏弱（强）、中国东部及日本上空850 hPa北风减弱（加强）;对流层中层东亚大槽减弱北缩（加深南进）、对流层高层西风急流减弱（加强）。风暴轴活动与冬季影响中国的冷空气活动次数相关关系显著。     

1996年6月500hPa环流指数、环流特征量资料

１９９６年６月５００ｈＰａ环流指数、环流特征量资料国家气候中心气候预测室环流指数西太平洋副热带高压东亚槽极涡月平均候平均１２３４５６面积指数强度指数西伸脊点脊线位置北界位置平均位置平均强度中心位置经度纬度强度亚欧ＩＺ０．８６１．００１．０２０．８８０...     

资料

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资料

１９９９年３月５００ｈＰａ环流指数、环流特征量资料国家气候中心气候预测室环流指数西太平洋副热带高压东亚槽极涡月平均候平均１２３４５６面积指数强度指数西伸脊点脊线位置北界位置平均位置平均强度中心位置经度纬度强度亚欧地区ＩＺＩＭ０．９９０．５２０．９９０...     

资料

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资料

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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.