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1.
利用条件非线性最优扰动(CNOP)方法,对2002年发生在西太平洋上的台风“风神”和“凤凰”之间的相互作用进行研究。CNOP方法可揭示出“风神”对“凤凰”单向引导作用的过程,表现为若将“凤凰”所在区域作为验证区域,用CNOP方法识别的敏感区主要位于“风神”所在区域,呈现出环绕“风神”的半环状结构;若将“风神”所在区域作为验证区域,则CNOP方法所识别的敏感区主要位于“风神”与副高交界的地方,远离“凤凰”所在的区域,可见,“风神”主要受副高的影响。敏感性试验表明,CNOP所识别的敏感区内误差的发展要大于台风中心周围区域内初始误差的发展,且在全场误差的发展中占有较大的比重,说明CNOP所识别的敏感区对验证区域的预报有较大的影响。   相似文献   

2.
郑家骅 《四川气象》1996,16(4):58-61
针对四川暴雨频发,灾重的特点和防汛气象服务准确及时,全程系列的要求,设计四川省暴雨预报警报服务系统,要在暴雨探测,通信、预报,综合信息,灾害评估和防灾对策研究的基础上,建立省级信息发布中心和决策服务政府专线,充分发挥中期预警,短期消息、临近警报,应急体制“四度设防”的功能效应急体制加强主体作用,完善联防机制,健全组织结构,提高运行效果,取得最佳效益。  相似文献   

3.
应用1999—2003年中国中央气象台 (CMO)、日本气象厅 (JMA) 以及美国联合台风警报中心 (JTWC) 发布的西北太平洋热带气旋综合预报资料, 从总误差、逐年误差趋势、不同海区误差、不同路径趋势误差、不同强度趋势误差等5个方面对各预报中心的路径及强度预报结果进行分析, 结果表明:5年总的平均误差以JTWC的路径预报误差最小, 而JMA的强度预报较准确; 在不同海域, 各预报中心的路径预报能力各有优势, 但在热带气旋的强度预报方面, JMA的方法在各海区都较稳定; 对不同路径趋势热带气旋的预报方面, 除了南海转向热带气旋的路径预报比JMA和CMO稍差一些之外, JTWC的路径预报在大多数情况下都是好于或相当于JMA和CMO; 在不同强度变化趋势热带气旋的预报方面, JTWC在大多数情况下都优于其他中心。上述结果帮助业务和科技人员全面了解各预报中心的预报能力优劣, 也为今后改进我国的热带气旋预报提供有益的参考。  相似文献   

4.
给出了一个嵌套于欧洲中期天气预报中心全球谱模式中的套网格模式,用于预报热带气旋路径趋势,提出了一种以欧洲中期天气预报中心提供的时距为24小时的预报场为基础的“接力预报”方法;设计了五种不同的“接力预报”方案;并对8507号和8509号两个热带气旋就各种不同预报方案进行了数值预报试验。结果表明,本模式对热带气旋路径趋势具有较强的预报能力,对疑难路径也具有一定的预报能力,为开展热带气旋的路径趋势预报提供了一个新的途径。文中还对影响热带气旋路径趋势的一些主要因子结合各预报结果进行了分析,为模式尽早投入业务提供了一定的依据。  相似文献   

5.
以台风路径数值预报的短时效预报偏差和目标时效(指所需订正的时效)的纬度预报为预报因子,采用多元线性回归方法建立了台风路径预报的偏差预估方程,继而对台风路径预报进行实时订正。本文以12 h为短时效,通过对欧洲中期天气预报中心确定性预报模式(ECMWF-IFS)和集合预报模式(ECMWF-EPS)的台风路径预报的应用,得到以下结论:2018年试报结果表明,24 h、36 h、48 h、60 h、72 h、84 h订正后的ECMWF-IFS台风路径预报的平均距离误差分别比订正前减小了7.3 km、9.3 km、8.9 km、6.5 km、6.9 km、2.6 km,总体来说较强台风(指12 h的台风强度实况≥32.7 m s?1)路径预报的订正效果更好。尝试了先对ECMWF-EPS各成员的台风路径预报进行订正,再进行集成预报,并对比了以下5种方式得到的台风路径预报:“订正后的确定性预报”、“所有集合预报成员集合平均”、“优选集合预报成员集合平均”、“所有集合预报成员先订正再集合平均”和“优选集合预报成员先订正再集合平均”,2018年试报结果表明,对于平均距离误差,24 h和36 h“优选集合预报成员先订正再集合平均”最小,48 h和60 h“所有集合预报成员先订正再集合平均”最小,72 h和84 h“优选集合预报成员集合平均”最小,如果在业务中有针对性地进行应用,有望获得一个在各预报时效表现都较优异的台风路径客观综合预报结果。24 h、36 h、48 h、60 h“优选集合预报成员先订正再集合平均”的平均距离误差分别比“所有集合预报成员集合平均”减小了13.3 km、11.7 km、10.0 km、7.6 km,比中央气象台官方预报(对应的时效为12 h、24 h、36 h、48 h)减小了0.7 km、2.0 km、3.9 km、2.4 km。  相似文献   

6.
决策树方法在一次历史异常雷电活动中的预报能力检验   总被引:1,自引:0,他引:1  
利用ncep1°×1°再分析资料和四川闪电定位仪监测网的监测资料,基于四川雷电潜势预报决策树的三类预报因子,针对2008年9月22~25日四川盆地西北部连续性雷电活动过程,重点分析了连续性雷电活动的环流背景和主要天气影响系统、热力结构特征、动力结构特征,检验了基于决策树方法筛选出的雷电潜势预报因子对连续性雷电活动的预报能力.结果表明:1)“9·23”连续性雷暴天气过程存在对流性雷暴以及副高和地面冷空气共同作用下形成的雷暴时段.雷暴区内始终存在着高能不稳定的热力条件,具有“对流层中低层正涡度、对流层高层负涡度”的典型雷暴动力结构.2)雷电潜势预报决策树的三大类预报因子能较好地预报本次雷电活动.  相似文献   

7.
利用1949—2021年中国气象局台风最佳路径资料、2022年中央气象台台风路径和强度实时业务资料、欧洲中期预报中心ERA-Interim逐6 h再分析资料等,对2022年西北太平洋和南海台风活动的主要特征进行分析。结果表明:2022年,台风活动的阶段性、群发性特征明显,生成位置偏北偏西,登陆我国的台风数量偏少、强度偏强,自2019年以来,已连续4年登陆台风个数偏少。预报误差分析表明,在台风生成初期、台风与西风带结合后转向以及多台风(低压)活动期间的路径预报误差较大。进一步分析台风暹芭、梅花和轩岚诺的预报难点,结果表明:“暹芭”北侧的大陆高压和高层急流的预报偏差是导致后期路径预报调整的主要原因;“梅花”登陆后陆上路径预报偏差主要由模式对引导气流的预报偏差所致;“轩岚诺”路径和强度变化复杂,在其快速加强和快速减弱的速率、结构变化导致的强度波动和尺度变化等方面存在预报偏差。  相似文献   

8.
利用华南精细数值天气预报模式,设计了无同化资料(CTRL)、同化雷达反演水汽(EXP1)以及同化雷达反演水汽、地面和探空资料(EXP2)三个试验,对2017年登陆广东沿海的四个台风降水预报与路径预报进行模拟,以评估资料同化对登陆台风短期降水预报、路径预报的影响。分析结果如下:雷达反演水汽同化后对未来24小时降水预报技巧均有正的改善,对台风路径预报影响不大;在此基础上同化地面、探空资料后对台风路径预报有改进,对降水预报改进不明显(与EXP1比)。通过诊断分析台风“玛娃”,发现模式初值场水汽的增量配合对流上升区有利于短时间内成云致雨,从而提高短时降水预报;地面及探空资料同化有利于登陆台风的短时路径预报。   相似文献   

9.
GRAPES-REPS西南低涡预报检验评估   总被引:5,自引:4,他引:1  
王静  陈静  钟有亮  张进  李晓莉 《气象》2017,43(4):385-401
利用2015年6—8月GR APES-REPS(Global/RegionalAssimilation and Prediction System-Regional Ensemble·Prediction System)区域集合预报资料,并设计西南低涡格点资料客观识别方法对西南低涡中心位置进行定位,首先评估GRAPES控制预报对西南低涡的预报准确性,之后挑选出四次生命史较长的西南低涡过程,分析评估GRAPES-REPS对西南低涡发生、发展、移动及降水过程集合预报性能。结果表明:(1)GRAPES模式对西南低涡预报的命中率较高,空报率略大于漏报率。(2)GRAPES-REPS对西南低涡发生和发展的预报效果较好,绝大部分集合预报成员能预报西南低涡发生和发展过程,但对西南低涡发生时间预报总体偏早。(3)GRAPES-REPS对西南低涡移动路径在24 h预报时效内比较合理,且集合预报平均明显优于控制预报,24 h之后东移型西南低涡移动路径明显偏北。(4)GRAPES-REPS对西南低涡强度预报总体偏强,表现为中心正涡度值偏大,位势高度值偏低。(5)24 h预报时效内,西南低涡触发的小雨到大雨量级的降水概率评分均有较好表现,且落区与实况接近,而暴雨落区个别略有偏北,但基本吻合。24 h之后,由于东移型西南低涡移动路径偏北导致模式预报降水落区偏北。可见,模式对西南低涡强降水有一定预报能力,因此,提高GRAPES-REPS中尺度集合预报能力,将有助于改进西南低涡强降水预报。  相似文献   

10.
ECMWF数值产品在热带气旋(TC)路径预报中的应用分析   总被引:4,自引:1,他引:4  
将三次样条插值方法应用到欧洲中期天气预报中心(ECMWF)海平面气压场(MSLP)、850 hPa涡度场和风场,对2004—2008年西北太平洋(WNP)和南海(SCS)所有编号热带气旋(TC)进行路径预报。结果表明:基于850 hPa涡度场的TC预报效果好于气压场预报,而综合考虑850 hPa涡度场、风场和海平面气压场的预报效果最好,且有效预报次数更多。与中央气象台(CMO)主观定位及预报对比发现:ECMWF客观预报的0 h的TC平均路径误差为79.9 km,24 h平均客观预报误差大于中央气象台的主观误差,而48~96 h则小于中央气象台的主观误差;误差年际变化分析表明:主观预报水平进步缓慢,而客观预报水平进步明显。ECMWF客观预报效果优于中央气象台效果差的主观预报。  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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