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1.
利用2008—2017年甘肃省河东地区自动气象观测站冰雹观测资料和灾情资料,对收集到的符合标准的河东地区75个冰雹个例进行中尺度诊断,按照主要影响系统分为3种冰雹天气类型,对3种冰雹天气型雷达产品的统计特征和雷达回波特征进行对比分析,并选取典型个例进一步分析验证。结果表明,在3种冰雹天气型下,多普勒雷达产品的最大反射率因子(Zmax)及其所在高度(H(Zmax))区别较小,Zmax均大于50 dBZ,对应H(Zmax)也在2.0 km以上;回波顶高(ET)、核心区厚度(H)、45 dBZ以上质心高度(H45 dBZ)、风暴体大于等于30 dBZ所在最大高度(TOP)、垂直累积液态水含量(VIL)及垂直累积液态水含量密度(VILD)存在明显差异,西北气流型的H、H45 dBZ、TOP和VIL较高,低槽型的ET和低涡型的VILD较低;3种冰雹天气型出现回波悬垂的频率均在61.0%以上,低槽型出现三体散射和旁瓣回波的频... 相似文献
2.
使用江西自动站数据、MICAPS天气图资料、雷达拼图CR产品和单部雷达基数据等资料,采用统计分析、形态对比、特征提取等方法,对2017—2019年宜丰4次暴雨和大暴雨过程中的短时强降水天气的演变与回波特征进行分析,结果表明:(1)宜丰暴雨或大暴雨过程都出现了≥30 mm·h-1的短时强降水。(2)200 hPa赣北处辐散分流区中,500 hPa 588 dagpm线稳定维持在江西南部,赣北处于850 hPa西南急流的左侧及前端,形成上干下暖湿的不稳定层结;地面辐合线是短时强降水的主要触发系统。(3)在短时强降水期间,雷暴回波群中超级单体回波强度为60~65 dBZ,短带回波强度为50~55 dBZ,复合体回波强度为55~60 dBZ,絮状回波带回波强度为40~45 d BZ。(4)在单部雷达回波产品上,雷暴回波群、回波短带、复合单体回波和絮带状回波,组合反射率CR为40~65 d BZ,回波顶高ET为8~15 km,垂直液态水含量VIL为10~60 kg/m2,50 dBZ强回波顶高为5~12 km。 相似文献
3.
利用常规观测、自动站逐时雨量、新一代多普勒天气雷达和ERA-interim再分析等资料， 对2013-2018年6-8月天山北坡73次短时强降水过程的中尺度影响系统、对流风暴特征进行分析研究。结果表明：天山北坡短时强降水过程主要中尺度系统为低空急流、低空切变线或辐合线及地面中尺度高压前的辐合线；雷达回波形态分为合并加强型（占33.9%）、列车效应型（占39.0%）及孤立对流型（占27.1%）3类，其垂直剖面有“低质心”和“高质心”2种结构，且前者占多数；径向速度图上有81%的过程有逆风区。以集合箱线图25%百分位作为最低阈值，天山北坡短时强降水阈值为最大反射率因子强度≥46.5 dBZ、强回波中心（40 dBZ）顶高≥4.0 km、回波顶高ET≥8.6 km及垂直累积液态水含量VIL≥7.0 kg?m-2，并以典型个例进行分析。 相似文献
4.
为了做好江西雷电监测预警和预报服务工作，使用天气图资料、地面气象要素、雷电数据、江西WebGIS雷达拼图、单部雷达产品等资料，采用天气学、统计学和雷达气象学等分析方法，对2021年3月江西两次雷击事件进行分析，结果表明：（1）两次雷击事件是由超级单体和强单体回波系统影响产生。（2）超级单体回波有四个特征：①具有≥60 dBZ回波强度，并存有≥65 dBZ回波核；②强回波面积≥10×10 km2；③强回波梯度≤8 km；④在强回波移动方向的下风方有云砧形成的“前伸”回波结构；强单体回波的回波强度（没有回波核）、强回波面积、强回波梯度和“前伸”回波结构都弱于超级单体回波。（3）超级单体CR回波强度达到65 dBZ，ET回波顶高达到11～12 km，VIL垂直累积液态水含量达到60 kg/m2；垂直反射率因子RCS向移动方向倾斜、55 dBZ强回波顶高达到8 km、65 dBZ强中心悬挂在6 km高度；垂直径向速度VCS在强回波区存在速度对、-5～19 m·s-1 速度达到弱切变的强度。（4）强单体回波CR强度达到60 dBZ，ET顶高达到9～10 km，VIL垂直累积液态水含量达到50～60 kg/m2；强单体回波垂直反射率因子RCS倾斜角度弱于超级单体，55 dBZ强回波顶高达到8 km，60 dBZ强回波高度伸展到6 km，没有65 dBZ强回波中心；垂直径向速度VCS表现为正速度区分成上下两层。研究结果为江西雷电天气的监测预警和预报服务，减轻雷击灾害提供有指导意义的范例。 相似文献
5.
利用2010—2018年新疆105个国家站、1240个区域自动站逐时降水资料及8部多普勒天气雷达资料,从预报业务应用角度提出新疆短时强降水过程定义并遴选468次短时强降水过程,分析短时强降水影响系统环流配置和雷达回波特征。结果表明新疆短时强降水的影响系统主要有中亚低槽(涡)、西西伯利亚低槽(涡)、西北低空急流。造成新疆短时强降水的对流风暴主要有合并加强型、列车效应型和孤立对流单体型,其中合并加强型最多,占45.1%,孤立对流单体型占34.8%,列车效应型最少,占20.2%,且各区域对流风暴的影响比例也有一定差异。南疆短时强降水过程中多普勒雷达最大反射率因子强度(Z max)、强回波中心顶高(D max)、回波顶高(ET)、最大垂直累积液态水含量(VIL)预警阈值小于北疆,且伊犁州最大,阿克苏最小,伊犁州短时强降水以低质心回波为主,其他区域则为低质心和高质心回波。 相似文献
6.
利用青岛地区2011—2015年间32次短时强降水个例的雷达反射率因子、地面雨量站数据和FNL再分析资料对产生短时强降水的中小尺度系统和雷达回波特征进行分析,结果表明:造成短时强降水的中小尺度系统主要为与低空切变(槽)、台风倒槽或在偏南(北)气流中局地发展的对流相联系的辐合区或中小尺度辐合线;雷达回波多表现为中尺度强回波带,其移向与回波带长轴的夹角较小,或为局地发展少动的强对流单体;雷达回波剖面显示回波按质心高度可分为大陆强对流型和热带海洋型,大陆强对流型强降水的平均反射率因子垂直廓线强度总体明显强于热带海洋型,对流发展更加旺盛,热带海洋型强回波集中在低层,在近地面最强,而大陆强对流型回波悬垂明显,最强回波位于2km左右;针对大陆强对流型和热带海洋型两种不同类型的短时强降水,采用分型Z-I关系法进行定量降水估测能够较好地反映强降水的落区和极值,相比于固定Z-I关系法,20mm·h~(-1)以上雨强的相对误差由70%左右下降到30%左右。 相似文献
7.
利用地面观测资料和多普勒天气雷达探测资料,对2015－2016年山东省11站次,小时降水量超过100mm的强降水单体的风暴参数特征和形态结构演变特征及10分钟雨量变化情况进行了分析。10分钟雨量变化情况表明,15～20mm降水量出现次数最多,约 85%的降水量≥10mm,65%的降水量≥15mm;最大雨量多数在25mm以上,平均值是27.6mm;最大降水量所对应的站点上空最大反射率因子平均值为52.5dBZ,所对应Z-R关系与Z=250R1.28非常接近。强降水单体风暴参数和形态结构演变特征表明,强降水阶段C-VIL值多数在17～37kg?m-2之间,平均值为28kg?m-2,明显小于冰雹预警C-VIL阈值;DBZM值多数在52～58dBZ之间,平均值为55dBZ;HT值多数在2.2～5.8km之间,平均值为4.2km;TOP值多数在7.5～12km之间,平均值为9.9km;ET值多数在11～15km之间,平均值为13.1km;盛夏季节,强降水单体具有低质心特征,降水强度较大;强降水单体演变具有“列车效应”或移动缓慢特征。 相似文献
8.
为了更好地监测预警冰雹和雷暴大风等强天气，使用常规天气图、TBB云图、自动气象站、雷达拼图、雷达PUP产品等资料，对2021年5月10日江西雷暴回波群冰雹天气过程，采用中尺度气象学和雷达气象学等方法进行分析，结果表明：雷暴回波群中超级单体产生大冰雹并伴随雷暴大风天气，没有出现短时强降水；超单往往造成较大冰雹，强单出现较小冰雹；樟树、丰城的对流云系发展成为中尺度对流系统MCS。湿度锋区达到≥40%/100 km和温度锋区达到≥10℃/100 km时，就能够触发产生对流运动而形成新的对流回波；当原有对流回波移到锋区附近时，回波会快速发展加强，强回波面积迅速扩大。风暴跟踪信息STI能较好地指示超级单体和强单体回波的移动方向和移动速度，多条STI指向一致时可信度更高。超单CR在65 dBZ以上，强回波面积较大，VIL在60 kg/m2，V0.5有正负速度对，RCS有冰雹回波特殊结构特征；VCS有正负速度切变；强单CR在60～65 dBZ之间，强回波面积较小，VIL在45～50 kg/m2之间，V0.5不一定有速度切变，RCS冰雹回波特殊结构特征不明显，VCS表现在负值区中出现大值区。 相似文献
9.
强冰雹和短时强降水天气雷达特征及临近预警 总被引：10，自引：2，他引：8
利用恩施多普勒雷达和常规分析资料,详细对比分析了2007-2008年发生在恩施山区强冰雹和短时强降水天气过程中的雷达产品特征.在此基础上,找出了适合恩施山区强冰雹和短时强降水天气的雷达临近预警指标:选取负温区回波厚度≥7 km、CR强中心回波强度≥55 dBz、强回波梯度≥15 dBz·km-1、45 dBz强回波伸展高度≥7.5 km、累积液态含水量(VIL)密度≥3.2 g·m-3和雷达风廓线1.8～6.1 km风垂直切变均值≥2.3×10-3s-1作为强冰雹临近预警指标;当满足组合反射率(CR)强中心回波强度、VIL密度、40 dBz强回波伸展高度和雷达风廓线(VWP)上1.8～6.1 km风垂直切变值达43.0 dBz,1.1 g·m-3,7.0 km和1.9×10-3s-1,可以考虑该站点及附近地区进入短时强降水临近预警状态,并利用2009年发生的强冰雹和短时强降水天气过程检验了这些临近预警指标性能. 相似文献
10.
北京夏季强雷暴降水回波结构与闪电特征个例分析 总被引：3，自引：1，他引：2
利用北京市气象局短时临近交互预报系统（VIPS）资料,对2008年奥运会期间两次强降水天气过程雷达回波结构及闪电时空特征进行了细致分析。结果表明,局地性强雷暴降雨天气中,降雨率峰值与闪电活动峰值关系有超前也有略滞后的情况;关于云闪和地闪出现时间,云闪一般要超前地闪5～15min;强降水回波单体中,总闪电次数的70％以上出现在大于40dBZ的强回波区,当最大回波强度大于60dBZ时,云闪出现在强回波区的概率接近90％,说明回波强度越强,云闪出现在强回波区的概率越大;对云闪与雷达回波垂直结构分析发现,强降水单体中云闪发生的高度主要在6km以上,且云闪发生频数峰值出现在8～11km高度。 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
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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 
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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