一次强飑线云结构特征的卫星反演分析

利用NOAA卫星AVHRR资料,对2006年4月28日山东一次春季强飑线过程进行了分析,重点研究了卫星资料多光谱综合分析的强对流云微物理特征和卫星识别的对流强信号,并与雷达、FY-2C卫星观测资料进行了对比分析。结果表明:(1)RGB合成图能清晰地显示云顶的结构、纹理、云砧、组成、高度及云厚等信息,是一种很方便的分析工具。(2)多光谱综合分析归纳出卫星探测对流强信号:云顶的对流结构和纹理突出,有明显的云砧,云顶以小粒子为主,粒子有效半径Re随高度增长缓慢,云团上部存在明显的Re随高度递减带,云顶Re和-dRe/dT能定量指示对流的强弱。据此,卫星识别出强中心A比实际降雹提前了近1h,比飑线发生提前了2.5h,比多普勒雷达监测提前了近2h,特别是识别出的强中心B比实际降雹提前了近4h。卫星探测为强对流天气的监测预报和预警提供了一种新途径。     

庆阳市一次局地冰雹天气分析

利用常规气象资料和多普勒雷达资料,从天气形势、物理量场和雷达回波演变特征3方面分析了2006年8月2日庆阳市局地强降雹的天气过程。结果表明：此次降雹过程在500hPa高空环流形势场上呈典型的西北气流型,低层辐合、高层辐散,对流层中层正涡度区的耦合激发低层上升运动加强,有利于本地水汽向上输送;河套北部短波槽促使冷空气动力下传是这次局地强对流天气最主要的动力触发机制;从雷达回波的演变来看此次降雹并非是典型的冰雹云回波特征,而是由飑线造成的对流云相互碰并增强后产生的冰雹;同时卫星云图上云顶亮温的变化与对流云团的发展也有着很好的对应关系,单个云团的合并有利于能量的集中和加强,易于产生冰雹。     

一次弱对流天气降雹成灾的雷达回波特征分析

通过对新疆玛河流域一次冰雹天气雷达资料及地面实况资料的分析,研究弱对流云降雹的雷达反射率因子与径向速度场的回波特征,进一步探讨弱对流云降雹与0℃层高度较低及垂直风切变的关系：弱对流天气当日零度层高度值可作为分析弱冰雹云的依据;高低空风速的差异形成的风切变造成的动压力产生垂直加速度,使对流运动得到加强和维持,也是此次降雹的动力机制。分析此次天气,揭示了新疆玛河流域弱对流云降雹天气过程生消的一些重要特征和变化,对雹云的识别和分析具有一定的指导意义。     

关中北部一次冰雹天气不同雷达特征对比分析

利用常规气象观测数据、ERA-5再分析资料、两种波段多普勒雷达产品、FY-2F云顶亮温TBB资料对2020年5月21日陕西一次强对流天气过程进行分析。结果表明：强对流发生在有利天气背景和环境条件下,对流云自北向南迅速移动发展增强,强天气区位于对流云后部TBB等温线密集处;C波段雷达产品在风暴演变过程中识别出了线状回波、三体散射回波特征,风暴单体具有明显的悬垂结构,单体质心短时间内迅速下降对应地面出现大风,三体散射回波在高低仰角依次出现对地面降雹有指示意义;X波段雷达偏振参量在风暴单体发展与成熟阶段有明显差异,发展阶段利用融化层以上的ZDR柱可以对风暴单体发展趋势做出预判,成熟阶段融化层以下RHV在08～09且ZDR和KDP随高度降低不断增大的区域为降落冰雹融化区,可以作为地面降雹的预判。     

渭河下游一次强降水过程自动站资料分析

利用常规气象观测资料以及卫星和多普勒雷达监测资料,对2010年6月2日晋东南局地强降雹的天气过程进行分析。结果表明：此次降雹过程在500hPa高空环流形势场上呈典型的偏北气流型,低层辐合、高层辐散;蒙古脊前、冷涡后部偏北气流促使冷空气动力下传是这次局地强对流天气主要的动力触发机制;雷达回波演变显示位于低涡后部的强回波分布分散,呈现“爆米花”状;卫星云图上云顶亮温的变化与对流云团的发展有着很好的对应关系,孤立云团的合并使能量集中和加强,有利于冰雹的产生。     

三门峡市冰雹出现规律与防雹工作探讨

利用1971-2005年三门峡市冰雹天气过程资料,分析了冰雹时空分布特征、主要影响系统、本站要素指标及雷达回波特征等,结果表明:渑池县降雹次数最多,灵宝次之,卢氏最少;降雹集中在4-8月,13-19时降雹几率最高.三门峡降雹的天气形势主要有蒙古-华北冷槽、冷涡型和西北气流型.受上述天气系统影响时,500 hPa有冷平流,若地面连续2～3天增温增湿,有可能出现冰雹天气.此外,雹云雷达回波强度＞50 dBz,云顶高度＞10 km,云顶温度＜-40℃,垂直积分液态含水量有明显的跃升.是降雹的前兆.     

桂西北一次区域性冰雹天气过程分析

利用高空、地面资料,自动气象站资料和河池多普勒雷达资料,对2013年3月23日桂西北河池市区域性冰雹天气过程进行分析。结果表明:500hPa高原冷槽、850hPa切变线、地面弱冷锋是这次过程的影响系统;边界层辐合线为触发对流云提供了动力条件;冷云厚度是暖云厚度的2倍有利于冰雹天气的产生;适宜降雹的云顶亮温在-52℃到-62℃;当VIL值≥60kg/m2时,强回波附近将有冰雹出现;反射率因子图上的弓形回波,钩状回波,弱回波区,旁瓣回波、三体散射,是发布冰雹预警的重要指标。     

基于卫星云参数监测产品的贵州冰雹云指标分析

利用2018年贵州省12个冰雹个例资料,基于CPAS系统统计分析了冰雹个例的云顶高度、云顶温度、云有效粒子半径、云光学厚度、黑体亮温等卫星云监测产品的特征参数及其时间变化。结果表明:发生冰雹时回波云顶高度均在9 km以上,云顶温度均在-25℃以下,液水含量均在800 mm以上,云光学厚度均在40以上,发生冰雹时有效粒子半径大部分均在40μm以上,当Tbb达到-50℃且半小时内保持不变,对流云团对应的区域即将发生降雹,可考虑将其作为贵州省即将出现降雹的卫星监测指标判据。     

甘南高原“4.15”冰雹天气的多普勒雷达特征分析

利用甘南多普勒雷达资料分析了2014年4月15日甘肃省合作市强对流天气过程,结果表明:此次冰雹天气的雹云特征与甘肃中东部地区存在一定的差异,虽然出现了弱回波区、回波悬垂、50 d Bz以上强回波伸展到-20℃以上等甘肃中东部地区大冰雹的降雹特征,但没有出现大冰雹。垂直液态水含量突增时,可以预示降雹开始,但此次冰雹天气过程开始时,垂直液态水含量仅为5 kg/m~2,远远小于东部地区;随着对流云增强,垂直液态水含量达到15 kg/m~2。强对流附近出现的低空大风速区不一定是低空急流,也可能是对流云的出流。     

6·23龙卷FY-2G卫星云微物理特征分析

利用FY-2G静止卫星资料,采用多光谱综合分析方法,对2016年6月23日江苏盐城特大龙卷强对流灾害天气进行分析,重点分析强对流云微物理特征和识别强对流的卫星信号,并与雷达、TRMM卫星观测资料进行了对比分析。结果表明:(1)静止卫星RGB合成图能够可视化、便捷显示云微物理特征与发展趋势,对流云2区云团是产生龙卷的主云团,云系移动缓慢、位置基本保持不变是本次龙卷的特点,致使龙卷始终维持在盐城。(2)归纳出龙卷强对流云微物理特征和卫星信号为云顶高、云顶温度(T_(top))达到-80℃,存在过顶现象;云顶粒子有效半径(Re_(top))小、以小冰粒子为主,云砧结构明显,上部存在云粒子有效半径(Re)随温度(T)递减带;晶化温度(T_g)冷,达到同质冻结温度,对应有效半径(Re_g)小。08:00(北京时) FY-2G已探测到1、2、4区云团具有强对流发展潜势,通过卫星跟踪云团强弱变化,及时发现灾害性强对流天气发生云团,加强对该云团监测,提前预警强对流灾害性天气发生,为静止卫星应用于强对流天气监测预警提供新途径。     

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.     

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.     

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.     

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.