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1.
西北太平洋热带气旋生成数在不同资料集上的差异性比较 总被引：2，自引：2，他引：0
比较分析中国气象局(CMA)、美国台风联合警报中心(JTWC)和日本RSMC Tokyo台风中心(JMA)台风资料频次的年际、年代际变化和周期变化特征,结果表明,不同资料中心的热带气旋(TC)、台风(TS强度及以上的TC)生成数的气候值存在一定的差异,热带气旋生成数的差异较为明显,台风生成数的差异相对要小,CMA资料中热带气旋、台风生成数相对偏多;CMA与JTWC间热带气旋生成数年际间变化差异显著而难以忽略,其差异主要来自TD生成数的明显不同;三个中心关于台风生成数的一致性比较好,其中JMA台风资料与另外两个中心资料间的一致更好;CMA与JTWC西北太平洋热带气旋生成数的周期变化间无明显差异,但年代际间变化有明显差异,主要表现为1990年代的反位相;台风生成数资料可能在1960年代后期存在非均一性。 相似文献
2.
Based on the tropical cyclone data from the Central Meteorological Observatory of China, Japan Meteorological Agency, Joint Typhoon Warning Center and European Centre for Medium-Range Weather Forecasts （ECMWF） during the period of 2004 to 2009, three consensus methods are used in tropical cyclone （TC） track forecasts. Operational consensus results show that the objective forecasts of ECMWF help to improve consensus skill by 2%, 3%-5% and 3%-5%, decrease track bias by 2.5 kin, 6-9 km and 10-12 km for the 24 h, 48 h and 72 h forecasts respectively over the years of 2007 to 2009. Analysis also indicates that consensus forecasts hold positive skills relative to each member. The multivariate regression composite is a method that shows relatively low skill, while the methods of arithmetic averaging and composite （in which the weighting coefficient is the reciprocal square of mean error of members） have almost comparable skills among members. Consensus forecast for a lead time of 96 h has negative skill relative to the ECMWF objective forecast. 相似文献
3.
环境地转基本气流的计算及热带气旋运动与其偏差的统计分析 总被引：1，自引：0，他引：1
利用国家气象中心T63L16的1.875×1.875经纬网格点资料和中央气象台编号的热带气旋实时中心位置资料,计算了1996年全年25个热带气旋,共126个时次的环境地转基本气流,分析了环境地转基本气流的垂直分布特征,并对热带气旋的实际运动与环境地转引导气流的偏差(后文将称其为引导偏差,即热带气旋的实际中心位置与按引导气流推算出的位置之间的偏差)进行了分析,发现引导气流的计算区域不同,其引导偏差是不一样的。得到了引导气流的最佳计算区域,并且发现热带气旋运动与环境地转基本气流的垂直切变结构的关系以及引导偏差与引导气流的速度、气旋本身的初始纬度位置和强度等有关。结果还表明,200～1000 hPa的深层加权平均的基本气流的引导效果最佳,可作为最佳引导气流使用。了解这些规律和特征,对热带气旋运动预报具有一定的参考意义。 相似文献
4.
INTENSITY CHANGE CHARACTERISTICS OF TROPICAL CYCLONES IN THE WESTERN NORTH PACIFIC AS REVEALED BY THREE DIFFERENT DATASETS 总被引：2，自引：1，他引：1
Analyzed in this paper are the 20-yr(1991-2010)tropical cyclone(TC)intensity from three forecast centers in the Western North Pacific,i.e.China Meteorological Administration(CMA),Japan Meteorological Agency(JMA),and Joint Typhoon Warning Center(JTWC)of the United States.Results show that there is more or less discrepancy in the intensity change of a TC among different datasets.The maximum discrepancy reaches 22 hPa/6h(42 hPa/6h,33 hPa/6h)between CMA and JMA(CMA and JTWC,JMA and JTWC).Special attention is paid to the records for abrupt intensity change,which is currently a difficult issue for forecasters globally.It is found that an abrupt intensity change process recorded by one dataset can have,in some extreme cases,intensity change in another dataset varying from 0 to≥10 hPa/6h with the same sign or the opposite sign.In a total of 2511 cases experiencing rapid intensity change,only 14%have consensus among all the three datasets and 25%have agreement between two of the three datasets.In spite of such a significant uncertainty,the three datasets agree on the general statistical characteristics of abrupt intensity change,including regional and seasonal distribution,the relationship with initial intensity and TC moving speed,and persistence features.Notable disagreement is on very strong systems(SuperTY)and TCs moving very fast. 相似文献
5.
热带气旋强度资料的差异性分析 总被引：16，自引：4，他引：16
通过对比西北太平洋3个主要预报中心(中国气象局(CMA)、日本东京台风中心(RSMC Tokyo)和美国联合台风警报中心(JTWC))的16 a数据,分析了不同来源的热带气旋(TC)强度资料的差异性。结果表明:CMA与RSMCTokyo和JTWC的TC强度均值分别相差0.6和1.7 m/s,均通过1%信度的统计检验,即存在显著差异;3个中心对同一TC确定的强度最大差异超过30 m/s;CMA资料的台风数多于RSMC Tokyo和JTWC,年台风频数的均方差也最大,但是3个中心资料的各级TC频数差异均无统计显著性。对比有、无飞机探测时段的资料发现,对TC进行飞机探测可在一定程度上减小各中心在确定TC强度方面的分歧。为了初步了解上述资料问题对TC强度预报的可能影响,采用一个气候持续性预报方法,取不同来源的TC强度资料进行了4 a(2000—2003年)的预报。发现据JTWC资料所得TC强度预报有最大的均方根误差,RSMCTokyo的最小,CMA居中;据CMA和RSMC Tokyo(CMA和JTWC)资料,对相同TC相同时次24 h预报的平均绝对偏差达2.5(4.0)m/s,最大可相差16(21)m/s。可见,西北太平洋TC强度的基本资料问题增加了预报的难度。 相似文献
6.
Comparison of Three Tropical Cyclone Intensity Datasets 总被引：3，自引：0，他引：3
Analyzed in this paper are the 16-yr (1988-2003) tropical cyclone (TC) intensity data from three major forecast centers of the western North Pacific, i.e., China Meteorological Administration (CMA), Regional Specialized Meteorological Center Tokyo (RSMC Tokyo), and Joint Typhoon Warning Center (JTWC) of the United States. Results show that there are significant discrepancies (at 1% significance level) in the intensity of TCs among the three centers, with a maximum difference for the same TC over 30 m s-1. The flight reconnaissance over TC can minish the discrepancy to some extent. A climatic and persistent prediction model is set up to study the impact of initial data from different forecast centers on the prediction of TC intensity. It is obtained that the root mean square error (RMSE) of a 4-yr independent test is the largest using data from JTWC, while the smallest using data from RSMC Tokyo. Average absolute deviation in 24-h intensity prediction is 2.5 m s-1 between CMA and RSMC Tokyo data, and 4.0 m s-1 between CMA and JTWC data, with a maximum deviation reaching 21 m s-1. Such a problem in the initial value increases the difficulty in intensity prediction of TCs over the western North Pacific. 相似文献
7.
基于副热带奇异向量的初值扰动方法已应用于GRAPES （Global and Regional Assimilation PrEdiction System）全球集合预报系统,但存在热带气旋预报路径离散度不足的问题。通过分析发现,热带气旋附近区域初值扰动结构不合理导致预报集合不能较好地估计热带气旋预报的不确定性,是路径集合离散度不足的可能原因之一。通过建立热带气旋奇异向量求解方案,将热带气旋奇异向量和副热带奇异向量共同线性组合生成初值扰动,以弥补热带气旋区域初值扰动结构不合理这一缺陷,进而改进热带气旋集合预报效果。利用GRAPES全球奇异向量计算方案,以台风中心10个经纬度区域为目标区构建热带气旋奇异向量求解方案,针对台风“榕树”个例进行集合预报试验,并开展批量试验,利用中国中央气象台最优台风路径和中国国家气象信息中心的降水观测资料进行检验,对比分析热带气旋奇异向量结构特征和初值扰动特征,评估热带气旋奇异向量对热带气旋路径集合预报和中国区域24 h累计降水概率预报技巧的影响。结果表明,热带气旋奇异向量具有局地化特征,使用热带气旋奇异向量之后,热带气旋路径离散度增加,路径集合平均预报误差和离散度的关系得到改善,路径集合平均预报误差有所减小,集合成员更好地描述了热带气旋路径的预报不确定性;中国台风降水的小雨、中雨、大雨、暴雨各量级24 h累计降水概率预报技巧均有一定提高。总之,当在初值扰动的生成中考虑热带气旋奇异向量后,可改进热带气旋初值扰动结果,并有助于改善热带气旋路径集合预报效果。 相似文献
8.
基于ECMWF海平面气压场的热带气旋路径预报效果检验 总被引：4，自引：0，他引：4
将三次样条插值方法应用到欧洲中心(ECMWF)海平面气压场(24～120 h)进行热带气旋(TC)中心定位定强和误差计算,并与同期美国联合台风警报中心(JTWC)、日本气象厅(JMA)和中国中央气象台(CMO)综合预报进行路径误差对比分析。结果表明:72 h以内预报以JTWC表现最好,其次是JMA的综合预报,ECMWF客观预报最差,但ECMWF对于96 h和120 h的热带气旋(TC)中期路径趋势比JTWC综合预报有更好的参考价值。ECMWF对24～120 h TC中心定强偏高15～20 hPa。分别统计08时和20时TC路径预报误差发现,24 h和48 h二者没有差异,而72～120 h 20时预报水平好于08时。 相似文献
9.
Characteristics and Preliminary Causes of Tropical Cyclone Extreme Rainfall Events over Hainan Island 总被引：1，自引：0，他引：1
The characteristics of tropical cyclone(TC) extreme rainfall events over Hainan Island from 1969 to 2014 are analyzed from the viewpoint of the TC maximum daily rainfall(TMDR) using daily station precipitation data from the Meteorological Information Center of the China Meteorological Administration, TC best-track data from the Shanghai Typhoon Institute,and NCEP/NCAR reanalysis data. The frequencies of the TMDR reaching 50, 100 and 250 mm show a decreasing trend[-0.7(10 yr)~(-1)], a weak decreasing trend [-0.2(10 yr)~(-1)] and a weak increasing trend [0.1(10 yr)~(-1)], respectively. For seasonal variations, the TMDR of all intensity grades mainly occurs from July to October, with the frequencies of TMDR 50 mm and 100 mm peaking in September and the frequency of TMDR 250 mm [TC extreme rainstorm(TCER) events]peaking in August and September. The western region(Changjiang) of the Island is always the rainfall center, independent of the intensity or frequencies of different intensity grades. The causes of TCERs are also explored and the results show that topography plays a key role in the characteristics of the rainfall events. TCERs are easily induced on the windward slopes of Wuzhi Mountain, with the coordination of TC tracks and TC wind structure. A slower speed of movement, a stronger TC intensity and a farther westward track are all conducive to extreme rainfall events. A weaker northwestern Pacific subtropical high is likely to make the 500-h Pa steering flow weaker and results in slower TC movement, whereas a stronger South China Sea summer monsoon can carry a higher moisture flux. These two environmental factors are both favorable for TCERs. 相似文献
10.
The abilities of typhoon (TC) track prediction by a medium-range forecast model T213L31 at National Meteorological Center are analyzed and its ability to improve its TC forecasts is discussed. The results show that about 57% of the TCs could be predicted by T213L31 but the initial position errors are large.The 43% area without the prediction of TC tracks is concentrated between 13°N and 20°N and east of 120°E and lack of conventional observation data is the main reason for the absence of TC prediction in this area.The adding of bogus TC could improve the ability of TC track prediction when there is no TC vortex in the analysis field, but could only have positive effects on the short-range TC track prediction when there is TC vortex in the T213L31 analysis field. 相似文献
11.
应用国家气象中心的T213L31模式对2006—2009年热带气旋路径数值预报的结果从平均距离误差、距离误差分布、模式系统性偏差、平均全移速误差、模式对背景场的预报偏差进行全面检验分析表明:对于不同走向的热带气旋 (简称TC) 路径预报而言,预报误差最小的是西行路径TC,预报误差最大的是东北行路径TC。按照TC强度进行分类统计发现,TC强度强比强度弱的路径预报平均距离误差小。T213对所有样本的平均预报而言,存在西北偏西向的系统性偏差,不同类型路径TC存在不同的系统性偏差。通过计算平均全移速可以看出,对于西北行、西行、北上类型路径在整个预报时效中移速偏差较小,而对于所有转向类路径移速偏差较大,即偏慢较明显。对T213模式预报2009年TC路径误差较大的个例 (0904,0906,0907号热带气旋) 检验模式对背景场的预报偏差,个例分析表明:模式对中高纬度西风槽预报偏强、对TC环境风场垂直切变预报偏大、对两个相近的TC预报更容易发生藤原效应,这些因素是导致TC路径偏差的主要原因。 相似文献
12.
使用中国气象局热带气旋资料中心的热带气旋最佳路径数据集和NCEP/NCAR再分析资料提供的月平均数据,对北上影响山东的热带气旋（tropical cyclone,TC）及其造成的极端降水进行统计分析,并揭示了有利于 TC北移影响山东的大气环流特征。结果表明：影响山东的 TC主要出现 于 6—9 月,其中盛夏时节（7、8 月）TC对山东影响最大;TC影响山东时,强度主要为台风及以下等 级,或已发生变性;TC会引发山东极端降水事件,TC极端降水多出现在夏秋季（7—9 月）,其中8月的占比最大,9月次之,TC降水在极端降水事件中的占比约为 10%,但年际变化大,有些年份占比达60%以上,特别是1990 年以来 TC对极端降水的贡献显著增强;影响山东的 TC主要生成于西 北太平洋,多为转向型路径;当500 hPa位势高度异常场呈太平洋一日本遥相关型的正位相时,TC更易北上影响山东,此时西北太平洋副热带高压位置偏北,其外围气流会引导TC北上转向,对华东地区造成影响;850 hPa上,南海至西北太平洋存在异常气旋式环流,对流活跃,夏季风环流和季风槽加强,有利于TC的生成和发展,同时,华东、华南上空有异常上升运动,涡度增大,垂直风切变减小,水汽充沛,TC登陆后强度能得到较好的维持。 相似文献
13.
This is a study to compare three selected tropical cyclone datasets separately compiled by CMA
Shanghai Typhoon Institute (CMA_SHI), the Joint Typhoon Warning Center (JTWC), and the Japan
Meteorological Agency (JMA). The annual frequencies, observation times and destructive power index as
the characteristic quantities are investigated of the tropical cyclones over the western North Pacific. The
comparative study has resulted in the following findings: 1) Statistical gaps between the datasets compared
are narrowing down as the intensity of tropical cyclones increases. 2) In the context of interdecadal
distribution, there is for the 1950s a relatively large gap between the datasets, as compared with a
narrowed gap for the period from the mid 1970s to the 1980s, and a recurring widened gap for the mid and
late 1990s. Additionally, an approach is proposed in the paper to correct the wind speed data in the TC
Yearbook. 相似文献
14.
Based on the Joint Typhoon Warning Center (JTWC) best-track dataset between 1965 and 2009 and the characteristic parameters including tropical cyclone (TC) position, intensity, path length and direction, a method for objective classification of the Northwestern Pacific tropical cyclone tracks is established by using K-means Clustering. The TC lifespan, energy, active season and landfall probability of seven clusters of tropical cyclone tracks are comparatively analyzed. The characteristics of these parameters are quite different among different tropical cyclone track clusters. From the trend of the past two decades, the frequency of the western recurving cluster (accounting for 21.3% of the total) increased, and the lifespan elongated slightly, which differs from the other clusters. The annual variation of the Power Dissipation Index (PDI) of most clusters mainly depended on the TC intensity and frequency. However, the annual variation of the PDI in the northwestern moving then recurving cluster and the pelagic west-northwest moving cluster mainly depended on the frequency. 相似文献
15.
利用1949—2006年西北太平洋及南海的热带气旋（TC）资料,分析了登陆我国的TC强度、登陆时间、登陆后路径趋向及强度变化等气候特征,并重点讨论了直接登陆华东和登陆台湾后再次登陆华东的TC路径和强度趋势差异。结果表明,直接登陆华东的TC比登陆台湾后再次登陆华东（以下简称为间接登陆）的TC更易北上或北上转向,而间接登陆的TC更易维持西偏北行;另外直接登陆华东的TC登陆后的强度更易维持,其登陆后路径趋向在西北偏西和西南方位的强度明显减弱的百分比率比其它方位的大。 相似文献
16.
THE RELATIONSHIP BETWEEN GLOBAL WARMING AND THE VARIATION IN TROPICAL CYCLONE FREQUENCY OVER THE WESTERN NORTH PACIFIC 总被引：3，自引：1，他引：2
The relationship between global warming and the variation in tropical cyclone (TC) genesis
frequency is analyzed using the data of the Tropical Cyclone Year Book by the China Meteorological
Administration and the National Centers for Environmental Prediction (NCEP) reanalysis data from 1949
to 2007. The observational results indicate that the average sea surface temperature (SST) in the
Intertropical Convergence Zone (ITCZ) region (10°N – 20°N, 100°E – 140°E) increases by 0.6°C against
the background of global warming, while the frequency of tropical cyclone geneses in this region decreases
significantly. Generally, the rise of SSTs is favorable for the genesis of tropical cyclones, but it is now
shown to be contrary to the normal effect. Most of the tropical cyclones in the western North Pacific (WNP)
are generated in the ITCZ. This is quite different from the case in the Atlantic basin in which the tropical
cyclones are mostly generated from the easterly wave. Our research results demonstrate that the ITCZ has a
weakening trend in strength, and it has moved much more equatorward in the past 40 years; both are
disadvantageous to the formation of tropical cyclones. Furthermore, our study also found that the ridge of
the subtropical high tends to shift slightly equatorward, which is another adverse mechanism for the
formation of tropical cyclones. 相似文献
17.
中国台风灾情特征及其灾害客观评估方法 总被引：5，自引：0，他引：5
利用上海台风研究所及国家气象中心整编的中国台风灾情资料,分析了中国致灾台风造成的人员伤亡、房屋倒损、农田受淹及直接经济损失等灾情特征.引入了定基物价指数,改进了台风灾害指数(ATDI指数)的计算方法,基于1980-2004年间所有致灾台风的灾害指数的聚类分析,将致灾台风的灾害分为:轻灾(或小灾)、中灾、大灾(或中偏重灾)和重灾4个等级,并据此对1980-2004年间中国致灾台风的灾情进行了客观评估.结果表明:平均每年约有7.2个台风对中国造成明显灾情,最多的年份多达11个、最少年份也有4个.中国致灾台风的频数逐年减少,但造成的灾情却逐年趋重,因台风而伤亡的总人数逐年上升(死亡人数下降)、倒损房屋和受淹的农田面积以及造成的直接经济损失均逐年递增,倒损房屋、受淹的农田面积、直接经济损失的年平均增长率分别为1.33×10~4间/年、2.28×10~4 hm~2/年和14.56亿元/年.1980-2004年间,单个致灾台风而言,倒损房屋、受淹的农田面积、直接经济损失的平均增长率分别为581.4间/个、880.0 hm~2/个和0.33亿元/个.从台风灾害指数看,1990年代中期,中国的台风灾害较为严重,其中1996年最重,而1998年则是1980-2004年间台风灾害最轻的年份. 相似文献
18.
Chang-Hoi HO Joo-Hong KIM Hyeong-Seog KIM Woosuk CHOI Min-Hee LEE Hee-Dong YOO Tae-Ryong KIM Sangwook PARK 《大气科学进展》2013,30(5):1260-1274
Recently, the National Typhoon Center (NTC) at the Korea Meteorological Administration launched a track-pattern-based model that predicts the horizontal distribution of tropical cyclone (TC) track density from June to October. This model is the first approach to target seasonal TC track clusters covering the entire western North Pacific (WNP) basin, and may represent a milestone for seasonal TC forecasting, using a simple statistical method that can be applied at weather operation centers. In this note, we describe the procedure of the track-pattern-based model with brief technical background to provide practical information on the use and operation of the model. The model comprises three major steps. First, long-term data of WNP TC tracks reveal seven climatological track clusters. Second, the TC counts for each cluster are predicted using a hybrid statistical-dynamical method, using the seasonal prediction of large-scale environments. Third, the final forecast map of track density is constructed by merging the spatial probabilities of the seven clusters and applying necessary bias corrections. Although the model is developed to issue the seasonal forecast in mid-May, it can be applied to alternative dates and target seasons following the procedure described in this note. Work continues on establishing an automatic system for this model at the NTC. 相似文献
19.
介绍了在MM5模式基础上建立起来的辽宁省热带气旋模式预报业务系统及2005年的预报情况。系统以T213L31产品为背景场和侧边界,初始场中同化了常规探空报、地面报及一些卫星反演资料,模式的初值中还嵌入人造热带气旋进行模式运算。系统每日自动运行2次;模式输出结果经后处理后,编写到通用绘图软件GrADs中,以图形显示,并在沈阳区域气象中心局域网的中尺度数值预报网页上显示。2005年汛期热带气旋预报表明,系统对热带气旋的路径和暴雨的预报效果较好。 相似文献
20.
登陆台湾岛热带气旋强度和结构变化的统计分析 总被引：2，自引：0，他引：2
利用1949—2008年共60年的《台风年鉴》、《热带气旋年鉴》资料及CMA-STI热带气旋最佳路径数据集,2001—2008年美国联合台风警报中心(JTWC)热带气旋尺度相关资料及日本气象厅(JMA)的TBB资料,统计分析西北太平洋(包括南海)热带气旋(TC)在登陆台湾过程中强度和结构变化的基本特征,主要结论有:(1)TC登陆台湾时强度为台风及以上级别的样本数占总样本数约60%,主要出现在6—9月,东部登陆TC的强度一般比在西部登陆的强;(2)大部分TC在岛上维持6 h左右,登陆时最大风速≤5级和强度为超强台风的TC穿越台湾岛时移动比较缓慢;(3)126个登陆台湾的TC样本过岛后近中心海平面气压平均增加5.61 hPa,近中心最大风速平均减小3.58 m/s,在台湾东部地区登陆TC的衰减率比在西部登陆的大3倍左右;(4)TC在登陆台湾前6 h至离岛后6 h期间其8级和10级风圈半径均明显减小,TC形状略呈长轴为NE-SW向的椭圆状,而其最大风速的半径却逐渐增大;(5)TBB分析结果显示,TC登陆台湾前,其外围对流主要出现在南侧和西侧,结构不对称,登陆以后,TC北部及东部的对流显著发展,外围结构区域对称;但中心附近的强对流则从登陆前6 h开始逐渐减弱消失。表明TC穿越台湾过程中内核结构松散、强度减弱。 相似文献