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1.
基于对流参数的洋口港地区雷暴预报方法研究   总被引:2,自引:0,他引:2  
文章分析了洋口港地区2001-2009年4-9月1645个样本22种对流参数与雷暴事件的相关性以及这些参数的统计特征。结果表明,各对流参数月际分布差异较大,各参数与雷暴事件相关系数也不同。因而选择沙氏指数SI、全总指数TT、杰弗逊指数JI、抬升凝结高度温度tcl_t、上下层温差dt_58、大气可降水量Pw、风暴强度指数SSI等7个对于雷暴活动具有较好相关性的因子,并考虑到4-9月月际分布差异,使用不同月份Pw、SI、TT、JI的不同阈值作为排空因子,不’同月份SSI、tcl_t、dt_58的不同阈值作为预报因子,使用二级逻辑回归法建立排空方程和预报方程,同时对所建立各月预报方程进行了检验和拟合结果分析,并对2010年4-9月样本进行试报,预报效果较好。  相似文献   

2.
动力-统计方法在24小时雷暴预报的应用   总被引:4,自引:1,他引:3  
曾淑玲  巩崇水  赵中军  李旭  周甘霖  王式功  尚可政 《气象》2012,38(12):1508-1514
利用T213数值预报产品,计算了多个对流参数,应用事件概率回归方法分别建立了全国690个基本站4-9月的24h雷暴潜势预报方程,并根据TS评分值最大的原则确定了雷暴发生预报的临界概率,针对2010年4-9月进行试预报。研究结果表明:(1)基于T213输出产品计算得到的对流参数物理意义明确,与雷暴有无事件相关系数较高,对雷暴潜势预报方程贡献很大。(2)雷暴潜势预报方程对区域性雷暴的预报指示性较强,尤其对于雷电频发的地区效果更好。(3)690个站TS评分平均值为0.24。  相似文献   

3.
文章以武川县某风电场为分析区,选取对流有效位能、K指数、抬升指数、700h Pa假相当位温、垂直速度等5个对雷暴具有较好指示意义的预报因子,利用2010—2011年5—9月武川站雷暴日资料和NCEP/NCAR逐6h的1o×1o再分析资料建立雷暴潜势预报方程,为风电场安全运行提供依据。对2012年雷暴预报效果检验表明,该方程对雷暴天气具有一定的预警能力,预报方程的命中率为80.6%,虚假报警率为67%,能够成功预报出该风电场两次较为严重的雷击事故,可用于支撑该风电场的雷暴预警服务。  相似文献   

4.
基于对流参数的雷暴潜势预报研究   总被引:14,自引:1,他引:14       下载免费PDF全文
郝莹  姚叶青  陈焱  边富昌 《气象》2007,33(1):51-56
为提高雷暴天气的潜势预报能力,在统计分析安徽省雷暴形成天气条件的基础上,利用2003-2004年T213资料,选取与雷暴相关性好的对流参数作为预报因子。并在考虑因子季节变化特征的基础上,分别用判别分析法和指标叠加法制作雷暴潜势预报,结果表明指标叠加法优于判别分析法。最后用指标叠加法试报了2005年3—8月的雷暴,临界成功指数CSJ=69.4%,命中率POD=89.5%,虚假报警率FAR=24.4%,分区预报准确率也较高。另外,试报期间的区域性冰雹、雷雨大风全部命中,可见该方法对冰雹、雷雨大风也有较好的指示意义。  相似文献   

5.
通过对2006年6~9月(雨季)大量雷暴对流参数进行计算,选取离西昌发射场最近的单点同化资料。利用相关系数法选取相关性好且稳定的预报因子,进行事件概率回归,得到雷暴预报方程。并对2007年雨季西昌雷暴进行预报,取得了较好的效果。分析表明,基于对流参数的雷暴预报方法对场区雷暴的预报具有明显的效果。   相似文献   

6.
基于NCEP/GFS资料的中国东部地区雷暴预报研究   总被引:2,自引:1,他引:1  
基于来自美国国家环境预测中心(NCEP)的GFS(Global Forecasting System)分析及预报场资料,将多个能够表征雷暴发生动力、热力环境的对流因子作为预报因子,通过费希尔判别准则及逐个引入因子法,建立集合多个对流参数的雷暴预报模型,从而进行较长时效(12—24 h)的区域性雷暴预报。依据临界成功指数(CSI)最高的原则,建立最优预报模型,不同地区所选用的对流参数不同,雷暴模型预报雷暴发生与否的临界值也不同,从而不仅能够得到较好的集合多个对流参数的雷暴区域性预报,还能充分考虑不同地区雷暴发生的地域性特点和气候背景。将建立的预报方法应用于2012年6和9月的两次强对流过程的预报,发现雷暴预报模型较好地预报出两次过程的雷暴落区。进一步,为了能够在强天气预报中客观有效地区分出雷暴与暴雨区,引入集合动力因子暴雨预报方法。集合动力因子暴雨预报方法在诊断和追踪强降水的发展演变中表现凸出,而集合对流参数雷暴预报方法则对包含短时强降水、冰雹、大风等在内的对流性天气有较好反映,综合两套预报方法各自的优势,建立了集成动力因子-对流参数强天气预报方法,用于降水和雷暴的预报,同时对雷暴加降水型、雷暴无降水型、降水无雷暴型等强天气进行区分预报。对中国多个典型城市的预报效果分析发现,该方法不仅能够较好地预报出较长时效(24 h)的雷暴和降水落区,对区分降水雷暴、无降水雷暴和无雷暴降水也表现出一定的能力。  相似文献   

7.
南京地区雷暴活动强度潜势预报   总被引:2,自引:0,他引:2  
利用江苏省2008、2009和2010年6 8月闪电定位资料对雷暴活动的强度进行了分级,并使用同一时段的探空资料计算了47个代表南京地区 环境层结特征的对流参数,利用其与雷暴活动强度的相关性选取预报因子.在此基础上,采用Bayes分类法和Logistic 回川归分析法,结合逐步选择法进一步筛选预报因子,分别建立了两种雷暴强度的预报模型.通过检验独立样本对比分析两种模型的预报效果,结果表明,Logistic回归分析法的Hedike技巧评分为0.396,并能识别出30%的强雷暴,而Bayes分类法的Hedike技巧评分为0.370,只能识别出5%的强雷暴.Logistic回归分析法对雷暴强度的潜势预报具有较好的指示意义.进一步分析进入预报模型的9个对流参数,表明雷暴活动越强时,低层空气越暖湿,中层空气越干冷,高低层的风切变越大.  相似文献   

8.
本文利用绵阳机场2010~2014年逐时气象观测资料、温江站探空资料与绵阳市闪电定位仪资料,通过探空资料计算各对流参数与雷暴发生的相关系数,筛选相关系数高的对流参数作为预报因子,并探讨各预报因子的物理意义。分别用事件概率回归(REEP)、Fisher判别分析以及指标叠加三种方法制作雷暴潜势预报,其中指标叠加法CSI评分最高,并且可以通过累加值N的大小来确定雷暴发生概率。用指标叠加法试报机场2015年6~8月雷暴,临界成功指数CSI=52.9%,击中率POD=81.8%,利用该方法对绵阳机场周边(市辖区范围)航路上的雷暴也有较好的预报能力。   相似文献   

9.
正1引言雷暴一般是指伴有雷击和闪电的局地对流性天气,俞小鼎等[1]通过主观临近预报和客观算法讨论了雷暴生成、发展和衰减预报技术;有很多学者基于大量的对流因子,选择各种不同的对流参数组合方案,建立了适合当地的雷暴潜势预报方程,刘宸钊等[2-3]结合对流参数,利用相关系数法选取相关性好且稳定的预报因子,进行事件概率回归,得到雷暴预报方程。郝莹等[4]利用T213资料计算和选取与雷暴相关  相似文献   

10.
基于达州市2015年10月—2016年9月的闪电定位和探空观测资料,以850 hPa与500 h Pa温差、大气可降水量、K指数、对流有效位能、对流抑制和抬升指数作为雷暴预警因子,利用投影寻踪动态聚类方法对该时段内的雷暴个例构建了预警模型。结果表明:(1)模型预报结果定量评估的临界成功指数为72.00%,该模型对个例达到了识别和预警效果;(2)该预警模型与常规预警方法相比,具有识别率高,计算简便,客观性强等特点,可为雷暴预警提供了一种新的客观预报方法。  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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