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1.
2006年5月26日和6月25日三门峡辖区均出现了以地面大风、冰雹为主的灾害性天气.利用常规观测资料和非常规加密探测资料以及雷达、卫星云图资料对这两次灾害性天气过程进行诊断分析,结果表明:这两次灾害性天气均是由500 hPa华北冷涡后部的下滑槽或横槽转竖带动北方冷空气急剧南下造成的下击暴流引发的强对流天气.当雷达回波顶高超过10 km、强度≥50 dBz并出现回波悬垂结构的超级对流单体或多单体超级对流风暴移来时,易产生强对流天气;强回波质心在移动过程中不断下降或回波悬垂结构、低层弱回波区出现在风暴后部时,是下击暴流发生的前兆;冰雹指数、风暴跟踪信息、中气旋3个产品叠加对强对流风暴发生、发展、移向的预报具有较好的参考作用.  相似文献   

2.
4.28临沂强对流灾害性大风多普勒天气雷达产品分析   总被引:9,自引:2,他引:7  
朱君鉴  刁秀广  曲军  黄秀韶 《气象》2008,34(12):21-26
分析了2006年4月28日发生在临沂的罕见灾害性大风的多普勒天气雷达产品.分析发现,雷达回波具有典型的弓状回波特征,在弓状回波前沿,对流单体强烈发展,出现有界弱回波区,低层入流缺口等超级单体的典型特征,风暴中出现中气旋,强降水之后风暴回波顶高、风暴质心高度、风暴的最大反射率因子高度迅速下降,灾害性大风出现在这个时段.实地考察表明,灾害性大风的路径与中气旋最大风速圈南缘移过的路径一致.分析认为,弓状回波后部存在较强后部下沉入流,由于强降水的拖曳作用,将中层中气旋的水平动量带到地面,中气旋右侧动量的方向与弓状回波后部的强下沉入流方向一致,两者叠加,使地面风速加大,造成灾害性大风.  相似文献   

3.
《湖北气象》2021,40(4)
利用地面观测资料、探空资料以及石家庄多普勒天气雷达和饶阳双偏振雷达资料等,对2018年6月13日影响河北中南地区的一个长生命史超级单体风暴的环流背景、雷达观测特征等进行了分析。结果表明:(1)此超级单体发生在涡后横槽转竖的环流背景下。(2)风暴生命史长204 min,其中超级单体维持时间长达138 min,其间雷达最大反射率因子基本上维持在65 dBz以上。(3)中气旋深厚并强烈发展是超级单体发展和维持的重要动力机制。中气旋底高最低可达风暴底部,顶高变化幅度较小,低质心中气旋和高质心中气旋的形成和发展都可能引起地面降雹,降雹期间对应超级单体短暂减弱。(4)超级单体维持期间一直伴有气旋、反气旋涡旋对特征。超级单体的钩状回波特征明显,表现为典型的回波墙-弱回波区-悬挂回波的垂直结构;低层辐合、高层辐散,高空辐散大于低层辐合,有利于超级单体内部强烈的旋转上升运动;有明显的三体散射和旁瓣回波,三体散射最长超过60 km,持续时间长达150 min。(5)双偏振雷达探测的超级单体反射率因子≥55 dBz,对应位置差分反射率-0.5~0.5 dB,差分传播相移率仅1.5~2.0°/km,相关系数在0.75~0.92之间,表明超级单体内同时存在液滴和较大冰雹。  相似文献   

4.

利用地面观测资料、探空资料以及石家庄多普勒天气雷达和饶阳双偏振雷达资料等,对2018年6月13日影响河北中南地区的一个长生命史超级单体风暴的环流背景、雷达观测特征等进行了分析。结果表明:(1)此超级单体发生在涡后横槽转竖的环流背景下。(2)风暴生命史长204 min,其中超级单体维持时间长达138 min,其间雷达最大反射率因子基本上维持在65 dBz以上。(3)中气旋深厚并强烈发展是超级单体发展和维持的重要动力机制。中气旋底高最低可达风暴底部,顶高变化幅度较小,低质心中气旋和高质心中气旋的形成和发展都可能引起地面降雹,降雹期间对应超级单体短暂减弱。(4)超级单体维持期间一直伴有气旋、反气旋涡旋对特征。超级单体的钩状回波特征明显,表现为典型的回波墙-弱回波区-悬挂回波的垂直结构;低层辐合、高层辐散,高空辐散大于低层辐合,有利于超级单体内部强烈的旋转上升运动;有明显的三体散射和旁瓣回波,三体散射最长超过60 km,持续时间长达150 min。(5)双偏振雷达探测的超级单体反射率因子≥55 dBz,对应位置差分反射率-0.5~0.5 dB,差分传播相移率仅1.5~2.0°/km,相关系数在0.75~0.92之间,表明超级单体内同时存在液滴和较大冰雹。

  相似文献   

5.
2017年江西副热带高压边缘雷暴大风回波特征   总被引:1,自引:3,他引:1  
利用MICAPS天气资料、WebGIS雷达拼图、自动站、强天气监测和雷电监测等数据,对2017年8月江西副热带高压边缘产生的4次雷暴大风天气过程,采用数据统计、形态特征对比等方法进行分析,结果表明:江西北部回波和南部回波发生辐合运动时,南面回波会发展的更为旺盛,形成飑线回波带。回波的传播方式一方面加快了回波移动速度,另一方面改变了回波的移动方向。副热带高压边缘雷达回波特征主要有两种:一是南北向短带回波,有时会发展为弓状回波;二是强回波单体,超级单体和复合单体回波。带状回波上,雷暴大风分布在回波带前沿,尤其是弓状回波带的头部,雷电分布则在回波带移动方向的后侧;强单体、超级单体和复合单体回波上,雷暴大风和雷电集中在强回波中心附近区域。超级单体回波具有55~60 dBZ块状回波结构,垂直液态水含量VIL达到60 kg·m~(-2);相对风暴速度SRM图上和垂直径向速度RHI_V图上,都具有相邻的正负速度对和达到中等以上中气旋标准。  相似文献   

6.
利用济南CINRAD/SA雷达探测资料,结合卫星、自动站和其他常规天气资料,分析了一次弓状回波和强对流风暴的发生、发展,弓状回波和强对流风暴合并形成新弓状回波后又演变成逗点回波的过程。结果表明:(1)强对流过程发生在东北低涡横槽转竖过程,大气环境具有较大的对流有效位能和中等强度的低层垂直风切变。FY-2C卫星的红外云图...  相似文献   

7.
高晓梅  马守强  王世杰  彭潇  魏涛 《气象科技》2018,46(6):1188-1200
利用常规地面和高空观测资料、加密自动站资料和多普勒雷达资料,对2016年6月山东两次强对流天气的雷达特征、环境条件等进行了对比分析,结果表明:6月14日强对流天气主要是横槽转竖引导冷空气南下引起,6月30日强对流天气发生在高空槽前、山东高低层受一致西南气流影响的环流形势下,地面辐合线是两次过程的触发机制。6月14日垂直风切变和风暴承载层平均风均比30日大很多,致使14日的超级单体风暴持续时间更长、强度更强。风暴相对螺旋度的大小对强对流天气强弱程度有指示意义。两次过程都在地面辐合线附近生成,都具有中气旋、高悬的强回波、有界弱回波区、回波悬垂、风暴顶辐散等雷达特征,不同的是14日具有倒V形缺口、中层径向辐合、冰雹散射和钩状回波等特征,30日具有窄带回波、径向速度大值区等特征。两次过程都出现了弱旋转对应地面都带来小冰雹天气,这在预报业务中值得注意。两次降雹与风暴单体高度及强度、垂直累积液态水含量及密度、中气旋厚度、最大切变和持续时间密切相关。  相似文献   

8.
利用常规观测资料、卫星资料以及多普勒天气雷达资料,分析了2016年4月27日午后发生在鄂西北的一次超级单体风暴过程。结果表明:高空冷槽、上干冷下暖湿、强垂直风切变等提供了良好的环境条件;汉江河谷喇叭口地形、湖陆风环流、中尺度地面辐合线以及低层暖湿气流产生的扰动与雷暴出流导致超级单体强烈增强;多普勒天气雷达特征表现为中气旋、低层有界弱回波区、典型钩状回波等超级单体特征,同时出现了三体散射、旁瓣回波等大冰雹特征;强的垂直风切变使得雷暴更有组织性并具有更长的生命史,有利于强对流天气的产生。  相似文献   

9.
利用MICAPS天气资料、江西WebGIS雷达拼图、自动站、强天气监测和雷电监测等数据,对2017年8月江西副热带高压边缘产生的四次雷暴大风天气过程,采用数据统计、形态特征对比等方法进行分析,结果表明:江西北部A回波和南部B回波发生辐合运动时,B回波会发展的更为旺盛,形成飑线回波带。当东北~西南走向的回波带,发生转向为南~北走向时,是形成弓状回波带的前兆。副高边缘对流单体回波分布很广,江西境内大多数地方都可以产生,雷暴大风发生在个别强回波或短带回波中。回波系统在不断向东移动过程中,其东南侧不断触发产生新的对流单体,通过不断合并,不断新生单体,形成向东东南方向“传播”的发展趋势,造成回波系统向传播方向移动。回波的传播方式一方面加快了回波移动速度,另一方面改变了回波的移动方向。副高边缘雷达回波特征主要有两种:一是南北向短带回波,有时会发展为弓状回波;二是强回波单体,超级单体和复合单体回波。带状回波上,雷暴大风分布在回波带前沿,尤其是弓状回波带的头部,雷电分布则在回波带移动方向的后侧;强单体、超级单体和复合单体回波上,雷暴大风和雷电集中在强回波中心附近区域。  相似文献   

10.
利用湖北省闪电定位仪、新一代天气雷达资料并结合常规气象观测等资料,对2011年7月24日下午出现在湖北襄阳的一次强雷暴天气过程进行了分析。该过程的两个强风暴分别产生了冰雹和雷雨大风(后期强降水),重点分析了两个强风暴系统生命期雷达回波和闪电(地闪)特征。结果表明:产生冰雹的强风暴是一个孤立的超级单体,降雹发生在超级单体成熟阶段;产生雷雨大风和强降水的强风暴是一个弓状回波,雷雨大风发生在弓状回波顶部,强降水回波成片状且移速较慢;两个风暴的地闪演变特征及闪电在风暴生命史各阶段分布的位置不同。  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 Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
<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(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.  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.
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   

18.
19.
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;  相似文献   

20.
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   

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