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Journal of Meteorological Research 2018年第3期32卷 394-409页

作者： Qiao LIU Tim LI weican zhou Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental ChangeCollaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and Technology University of Hawaii

This study investigates the impact of low-frequency(intraseasonal and interannual) steering flows on straight northward-moving(defined as a meridional displacement two times greater than the zonal displacement) typhoons over the western North Pacific using observational data. The year-to-year change in the northward-moving tracks is affected by the interannual change in the location and intensity of the subtropical high. A strengthened northward steering flow east of 120°E and a weakened easterly steering flow south of the subtropical high favor more frequent straight northward tracks. Examining each of the individual northward-moving typhoons shows that they interact with three types of intraseasonal(10-60-day) background flows during their northward journey. The first type is the monsoon gyre pattern, in which the northward-moving typhoon is embedded in a closed cyclonic monsoon gyre circulation. The second type is the wave train pattern, where a cyclonic(anticyclonic) vorticity circulation is located to the west(east) of the northward-moving typhoon center. The third type is the mid-latitude trough pattern, in which the northward-moving typhoon center is located in the maximum vorticity region of the trough.

关键词： intraseasonal steering flow interannual steering flow straight northward-moving typhoon

Factors controlling northward and north-eastward moving tropical cyclones near the coast of East Asia

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Frontiers of Earth Science 2019年第4期13卷 778-790页

作者： Qiao LIU weican zhou Melinda PENG Tim LI Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Key Laboratory of Meteorological Disaster Ministry of Education Nanjing University of Information Science and TechnologyNanjing 210044China Joint International Research Laboratory of Climate and Environmental Change Nanjing University of Information Science and TechnologyNanjing 210044China University of Colorado at Colorado University of Colorado at Colorado Spring Colorado SpringCO 80918USA International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHI 96822USA

The impacts of multi-time-scale flows on northward and north-eastward moving tropical cyclones(TCs)near the east coast of China in August and September are investigated using reanalysis data from 1982 to *** of interest are under the influence of the subtropical high-pressure system in the western North Pacific(WNP).In August when the subtropical highpressure system is strong and close to the coast line,most TCs in the region move northward,while more TCs move north-eastward in September when the subtropical highpressure system retreats to the *** investigate the influence from different time-scales,the environmental flow is divided intofour components,the synoptic flow,the intraseasonal flow,the interannual flow and the climatological background *** of steering flows between 25°N and 30°N indicates that the meridional steering vectors from all time-scales point to the north,dominated by the intraseasonal *** deciding factor on whether a TC moves to the north or north-east between 25°N and 30°N is the zonal steering *** the northward moving group,the sum of the zonal steering from all time-scales is very *** the other hand,the north-east moving group has a net eastward zonal component mainly contributed by the climatological mean *** individual cases that stood out from the majority of the group are *** those cases,the intraseasonal flow plays an important role in affecting the movement of the TCs mainly through the wave train,in which a cyclonic circulation is located to the north-west(north)and an anticyclonic circulation to the south-east(east)of *** analysis of the steering vectors indicates the importance of all components with different timescales to the movement of TCs.

关键词： northward moving TC north-eastward moving TC steering flow

Impacts of Steering Flows with Different Timescales on the Track of Typhoon Sanba(2012)

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Journal of Meteorological Research 2021年第2期35卷 343-357页

作者： Qiao LIU Melinda PENG weican zhou Tim LI Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044China University of Colorado Colorado SpringColorado 80918USA International Pacific Research Center and Department of Atmospheric Sciences School of Ocean and Earth Science and TechnologyUniversity of Hawaii at ManoaHonoluluHawaii 96822USA

Typhoon Sanba(2012),the strongest tropical cyclone(TC)of the year worldwide,moved northward almost along130°longitude during its lifetime and passed through different background flows from low to high *** steering flows with different timescales for Sanba are retrieved by using the NCEP reanalysis data with the total wind field separated into:a mean state,an interannual component,an intraseasonal component,and a synoptic *** analysis indicates that the intraseasonal timescale wave train(WT)with east–west oriented circulations made the largest contribution to the movement of *** effects of the environmental steering with different timescales on Sanba’s movement are investigated with numerical simulations using the Weather Research and Forecasting(WRF)*** the control simulation,total fields from the NCEP reanalysis are used as initial and boundary conditions,and the northward motion of Sanba is well *** sensitivity experiments,each of the intraseasonal and interannual components is removed one at a *** steering vectors associated with these timescales can explain their influences on the movement of Sanba in the *** budget analyses indicate that the horizontal vorticity advection made the largest contribution to the movement of the storm.

关键词： intraseasonal interannual mean state steering flow

Influences of the Three Gorges Dam in China on Precipitation over Surrounding Regions

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Journal of Meteorological Research 2017年第4期31卷 767-773页

作者： Yan LI weican zhou Xianyan CHEN Dexian FANG Qianqian ZHANG Key Laboratory of Meteorological Disaster of Ministry of Education Joint International Research Laboratory of Climate and Environment Changeand Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044 National Climate Center Beijing 100081 Chongqing Institute of Meteorological Sciences Chongqing 401147

Impacts of the Three Gorges Dam（TGD） in China on the regional pattern and annual amount of precipitation around the Three Gorges Reservoir（TGR） are examined by comparing observations before and after the operation of TGD（1984–2003 and 2004–13）. Empirical orthogonal function（EOF） analysis of the annual precipitation anomalies clearly indicates that the land-use change associated with the construction of TGD has not significantly changed the precipitation pattern. To investigate the impacts of TGD on the rainfall amount, we compare the relative variations of atmospheric variables related to precipitation formation in three spatial bands： over TGR, near TGR, and far from TGR. It is found that the differences in annual rainfall over TGD between the two periods before and after the operation of TGD are small, suggesting a weak impact of TGD on the rainfall amount. The TGD water level increased from 66 m before June 2003 to 175 m after 2010, and this may have slightly reduced precipitation on the local scale.

关键词： Three Gorges Dam precipitation empirical orthogonal function (EOF) analysis

Assessing the Influence of the ENSO on Tropical Cyclone Prevailing Tracks in the Western North Pacific

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Advances in Atmospheric Sciences 2010年第6期27卷 1361-1371页

作者：赵海坤吴立广周伟灿 Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology

Using a statistical model for simulating tropical cyclone （TC） formation and a trajectory model for simulating TC tracks, the influence of the El Nino-Southern Oscillation （ENSO） on the peak-season （July-September） TC prevailing tracks in the western North Pacific basin is assessed based on 14 selected El Nino and 14 selected La Nina years during the period 1950-2007. It is found that the combination of statistical formation model and a trajectory model can simulate well the primary features of TC prevailing tracks on the interannual timescale. In the El Nino years, the significant enhancement of TC activity primarily occurs south of 20°N, especially east of 130°E. TCs that take the northwestward prevailing track and affect East Asia, including Taiwan Island, the Chinese mainland, Korea, and Japan, tend to move more westward in the El Nino years, while taking a more northward track in the La Nina years. Numerical simulations confirm that the ENSO-related changes in large-scale steering flows and TC formation locations can have a considerable influence on TC prevailing tracks.

关键词： ENSO tropical cyclone track trajectory model western North Pacific

利用位涡反演方法对一次台风暴雨过程的成因分析

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大气科学学报 2021年第3期44卷 441-450页

作者：周伟灿罗丽君南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心江苏南京210044

采用NCEP FNL的客观分析资料、中国自动站与CMORPH的逐小时降水融合资料,对2015年8月23—24日发生在上海的一次强降水天气过程进行了天气学分析,并通过位涡反演方法对1515号台风“天鹅”在本次降水过程的具体作用进行了定量诊断分析,以... 详细信息

采用NCEP FNL的客观分析资料、中国自动站与CMORPH的逐小时降水融合资料,对2015年8月23—24日发生在上海的一次强降水天气过程进行了天气学分析,并通过位涡反演方法对1515号台风“天鹅”在本次降水过程的具体作用进行了定量诊断分析,以探讨本次暴雨过程的发生机制。得出以下主要结论:1)位涡反演方法能够较为准确地反映西风槽、台风及副热带高压等重要天气系统的位置及强度,能够较为有效地再现系统的演变过程;2)北方冷空气与远距离台风外围的东北气流交汇是产生本次降水过程的主要原因;3)通过对比原始场与剔除台风后的分析场,可以发现台风“天鹅”本身的扰动对应的水汽通量占比53.3%,是本次降水过程的水汽输入的主要贡献来源;4)台风“天鹅”对降水区域提供了一定的热力条件,在扣除台风后原分析场的大值区和暖湿舌消失,相应的锋区也消失。

关键词：台风暴雨位涡反演水汽贡献

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CAD电子图管理系统中全文检索的研究

微计算机信息 2006年第7S期22卷 216-218,50页

作者：许敏周伟灿南京信息工程大学硕士研究生210044

文章首先介绍了全文检索系统的概念,提出了电子图管理系统中全文检索系统的设计和实现,既继承了现今已有的全文检索系统的优点,并且在中文分词算法和机器字典存贮技术方面改进了目前通用的方法,比较结果显示无论是在检索速度还是在存储... 详细信息

文章首先介绍了全文检索系统的概念,提出了电子图管理系统中全文检索系统的设计和实现,既继承了现今已有的全文检索系统的优点,并且在中文分词算法和机器字典存贮技术方面改进了目前通用的方法,比较结果显示无论是在检索速度还是在存储效率上都优于目前已有的全文搜索系统。

关键词：电子图管理系统全文检索中文分词

超强台风“天鹅”(2015)路径突变过程机理研究

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大气科学 2018年第1期42卷 227-238页

作者：毕鑫鑫陈光华周伟灿南京信息工程大学气象灾害教育部重点实验彭气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心南京210044 中国科学院大气物理研究所季风系统研究中心北京100029

本文采用中国气象局的最佳台风路径数据和美国国家环境预报中心1°×1°每6 h再分析资料作为研究工作的基本场,运用了分部位涡反演方法探讨影响2015年第15号超强台风"天鹅"路径突变的物理机制,得到以下结论:(1)就天气系统而言,"天鹅"整... 详细信息

本文采用中国气象局的最佳台风路径数据和美国国家环境预报中心1°×1°每6 h再分析资料作为研究工作的基本场,运用了分部位涡反演方法探讨影响2015年第15号超强台风"天鹅"路径突变的物理机制,得到以下结论:(1)就天气系统而言,"天鹅"整个移动过程中都受到周围环境场及引导气流的影响,主要的影响系统包括西北太平洋副热带高压、季风涡旋、邻近台风"艾莎尼"及台风外围反气旋;(2)定量分析了与各影响系统扰动位涡相关的引导气流矢量,发现整个过程中超强台风"天鹅"的移动始终受西北太平洋副热带高压的影响,其次是来自季风涡旋及台风外围反气旋的贡献,而当"天鹅"有向北转向趋势时,与外围反气旋相关的东北向引导气流导致了台风的路径北折;(3)进一步定量分析了总扰动位涡在不同高度层上相关引导气流的贡献,结果表明在垂直方向上对流层中层系统的引导气流矢量与"天鹅"的移动最为吻合,而形成于低层系统的偏南风气流与"天鹅"向北突然转向有着密切的联系,并在转向后逐渐向中高层发展增强。

关键词：台风位涡反演路径突变引导气流

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1980—2009年我国龙卷事件变化

气候变化研究进展 2012年第3期8卷 183-189页

作者：冯婧周伟灿徐影南京信息工程大学大气科学学院南京210044 中国气象局气候研究开放实验室/国家气候中心北京100081

根据1980—2009年我国龙卷事件的变化特征,初步探讨了20世纪90年代以后龙卷事件显著减少的特征及原因。结果表明,1980—2009年龙卷事件呈现明显减少的趋势,20世纪80年代最多,90年代以后明显减少,尤其是夏季(7—8月),在我国东部地区减少... 详细信息

根据1980—2009年我国龙卷事件的变化特征,初步探讨了20世纪90年代以后龙卷事件显著减少的特征及原因。结果表明,1980—2009年龙卷事件呈现明显减少的趋势,20世纪80年代最多,90年代以后明显减少,尤其是夏季(7—8月),在我国东部地区减少最明显。对龙卷高发时段7—8月06时(UTC)对流有效位能(ECAPE)与深层垂直风切变(S06)以及二者乘积变量(ES)的分析表明:ECAPE和S06是影响龙卷的两个重要因子,ES的高值中心更好地对应于龙卷事件发生的集中区。地面气温的变化会影响ECAPE的变化。1980—2009年,我国华北平原地区7—8月S06明显下降是20世纪80年代以后我国华北地区龙卷事件减少的主要原因。

关键词：龙卷对流有效位能垂直风切变气温

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基于DSP的指纹识别系统设计

微计算机信息 2006年第5Z期22卷 169-170,223页

作者：衡骏遥周伟灿南京信息工程大学

本文提出了一种新型的基于DSP的独立指纹识别系统,构建了高速的数据采集系统。采用FPGA作为协处理器,分担数据计算和扩展接口,根据系统结构改进算法,以此实现一个高效低功耗的嵌入式系统。文中介绍了系统的组成原理、硬件结构设计以及... 详细信息

本文提出了一种新型的基于DSP的独立指纹识别系统,构建了高速的数据采集系统。采用FPGA作为协处理器,分担数据计算和扩展接口,根据系统结构改进算法,以此实现一个高效低功耗的嵌入式系统。文中介绍了系统的组成原理、硬件结构设计以及指纹识别算法的处理流程。通过实验,该系统满足实时性要求。

关键词：指纹识别 DSP算法 FPGA 脊线优化