四维变分同化方法在暴雨预报中的应用   总被引：7，自引：8，他引：7  

程小平  侯志明  费建芳  王云峰 《气象科学》2006,26(2):143-148

本文利用PSU/NCAR的MM5数值预报模式及其伴随模式,以我国1999年6月23日~6月24日的一次梅雨锋暴雨过程为个例,作了两组试验:控制试验和同化试验,并对两组试验的降水预报效果以及初始场进行对比分析,结果表明:四维变分资料同化方法可以将各种不同类型、不同时次的观测资料同化到模式中,将这些资料中有用的中尺度信息引入到模式初始场,有效改善初始场,从而提高暴雨预报水平。  相似文献   

05.7.23河北暴雨中尺度分析   总被引：2，自引：3，他引：2  

侯瑞钦  景华  张迎新  张文君 《气象》2006,32(7):88-94

利用常规观测资料和卫星、自动站、加密雨量站、多普勒雷达等资料，对2005年7月22—24日河北中南部大暴雨过程进行天气动力学和中尺度分析，结果表明：这次暴雨是在有利的大尺度环流下产生的；副热带高压及热带系统造成的低层水汽堆积及高层的强辐散为强对流发生提供了热力和动力条件；整个过程中主要有三个强对流云团活动，地面对应有3个中-β尺度雨团产生，雨团一般出现在中尺度辐合线或中尺度气旋性环流偏向暖湿气流一侧；强雷达回波和正负速度对、逆风区等特征对强降水具有指示意义。  相似文献   

关于晋城市人工影响天气发展的思考     

帅克杰  程海霞 《山西气象》2006,(3):40-41

本文分析了晋城市人工影响天气工作的现状,通过与先进地(市)比较,指出了存在的问题,并提出了以下对策:加强人工影响天气工作的领导和科学体系的建设;适应社会发展,拓宽服务领域;加强沟通协调,彻底解决空域申请难的问题;加大科研开发力度,加强人工影响天气队伍建设。  相似文献   

Deep-water sediments and evolution of the Lower Triassic Xikou Formation in southwestern Fujian, China   总被引：1，自引：1，他引：0  

Peijun Li  Quanlin Hou  Shu Sun  Jiliang Li 《中国科学D辑(英文版)》1998,41(6):639-647

The Lower Triassic Xikou Formation in southwestern Fujian, China is a set of complex deep-water sediments which includes turbidites, sandy contourites and isolated olistoliths. Five facies and seven subfacies are recognized in the deep-water turbidites, which are considered to belong to five facies associations of upper, middle and lower fans, respectively. The sandy contourites, which occur within turbidites as isolated thin layers with structures of traction current, are formed by reworking turbidites. They occur in discrete units, not as a part of a vertical sequence of structures, such as Bouma sequence. Paleocurrent directions derived from sandy contourites are perpendicular to or at a large angle of those derived from turbidites. In some areas, within the Formation there exist large oolitic limestone blocks slided from shallow sea. The temporal-spatial distribution of three types of sediments mentioned above and the related evidences could indicate that a passive continental margin from shallow sea to bathyal-abyssal region, dipping toward southeast, once occurred in study area during the early Triassic. The early Triassic represents a period of sealevel uprising. The uprising of sea level and the development of isolated olistoliths probably imply gradual shrinking of an ocean basin at that time. Project supported by the National Natural Science Foundation of China (Grant Nos. 49490011, 49702036).  相似文献   

A preliminary research establishing the present-time intraplate blocks movement model on the Chinese mainland based on GPS data   总被引：4，自引：0，他引：4  

Shuo-Yu Zhou  Yue-Gang Zhang  Guo-Yu Ding  Yun Wu  Xiao-Jun Qin  Shun-Ying Shi  Qi Wang  Xin-Zhao You  Xue-Jun Qiao  Ping Shuai  Gan-Jin Deng 《地震学报(英文版)》1998,11(4):403-412

The Chinese mainland is regarded as the best area for studying the continental crustal movement and dynamics. In the past, based on the ground surface observation, it was very difficult to study the movement of the intraplate blocks within a range of larger space and a time scale of several years quantitatively. In this paper, a method of calculating the Euler vectors of present-time motion among blocks by using Cardan angles has been given completely based on two periods of GPS repetition measurement data of the National Ascending Plan of China (NAPC) — the study and application of current crustal movement and geodynamics in 1994 and 1996. A present-time blocks movement model on the Chinese mainland (PBMC-1), which describes the motion of seven blocks—Tibet, Chuan-Dian, Gan-Qing, Xinjiang, South China, North China and Heilongjiang block, is established preliminarily. The velocity field of the relative motion among the intraplate blocks and boundary motion in the Chinese mainland are firstly given within several years time scale. It is shown by the results calculated with the model that the velocity-rate of each block is reduced gradually from the south to north and from the west to east, and the motion direction changes gradually from NNE to E, even SEE or SE. The collision of Indian plate plays a leading role in the movement of the intraplate blocks in the Chinese mainland, while the motion manner and velocity-rate of block boundary zone (fracture zone) depend on the motion of every block again. The present-time motion of a time scale of several years computed with the model is not only largely consistent with the average motion of a time scale of several million years derived from geology, but also very coincident with the results of geophysical and astronomic observation. It is shown preliminarily that the observed results of space geodesy techniques such as GPS etc. are capable of discovering the crustal movement at present. This study is supported by the National Natural Science Foundation of China (NNSFC), National Ascending Plan of China (NAPC) and Chinese Joint Seismological Science Foundation (CJSSF).  相似文献   

Estimating the Degree of Earthquake Risk from Fault Characteristics     

Hou Jianjun Bai Taixu Liang Haihua Han Mukang Department of Geology  Peking University  Beijing Ollier C. D. Center for Resource  Environmental Studies  Australia National University  Canberra ACT  Australia 《中国地质大学学报(英文版)》1998,9(3)

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试论幔柱构造与成矿系统——以三江特提斯成矿域为例   总被引：30，自引：4，他引：26  

侯增谦  李红阳 《矿床地质》1998,17(2):97-113

以三江特提斯成矿域为例,简述了幔柱构造特征,提出了“幔柱构造成矿体系”新观点。研究表明,热幔柱发育演化,导致大陆岩石圈向大洋岩石圈构造体制转化,伴随大陆活化、减薄、去根、张裂、解体和成洋诸事件;冷幔柱形成演变,导致大洋岩石圈向大陆岩石圈构造体制转变,并引发俯冲造山→碰撞造山→陆内造山过程。在幔柱构造制约下,一系列形成于不同构造背景、产出不同地质环境、具有不同成矿体制、不同序次组合和不同成矿类型的矿床成矿系列组合和矿床成矿谱系,共同构成统一的成矿体系。热幔柱成矿体系包括热幔柱热点和热幔柱－扩张脊２大次级成矿系统,冷幔柱成矿体系包括冷幔柱－俯冲造山、冷幔柱－碰撞造山和冷幔柱－陆内造山３大次级成矿系统。最后,按成矿体系,成矿系列和矿床三级体制对三江特提斯成矿域主要矿床形成条件和成矿规律进行了全新分析。  相似文献   

西准噶尔东部碱性花岗岩体侵位机理的岩浆动力学初步探讨   总被引：1，自引：0，他引：1  

杨富贵  洪文兴 《矿物学报》1998,18(4):411-416

运用岩浆动力学原理探讨了西准噶尔东部碱性花岗岩浆侵位的驱动力、上升通道、通道最小临界宽度和定位过程。指出：碱性花岗岩体是由其岩浆主要在区域性挤压应力作用下,沿深大断裂以最小临界宽度1．33～301m的脉状上升,并在地壳浅部发生气球膨胀和岩墙扩张．定位于与区内深大断裂有关的次级张性裂隙发育部位后形成的。  相似文献   

小波分析及其在勘查地球物理中的应用   总被引：8，自引：2，他引：6  

侯遵泽 《物探与化探》1998,22(1):71-75

本文介绍小波分析的基本方法原理及其在地球物理方法研究中的应用成果,指出了小波分析具有更广阔的应用前景。  相似文献   

Study on rust layers on steel in different marine corrosion zone   总被引：1，自引：0，他引：1  

李言涛  侯保荣 《中国海洋湖沼学报》1998,16(3):231-236

IrmODUCnONTheMossbaureffect(ME)isalsoknOWnasrecoil-thenuclearresonaneabsorp-hon.MossbaursPeCboscoPy(MS)haspIDvedtobeaveryuSefultecheqUeforstudytngcormsionPimessesandcedon-cts.TheInainadvantagsofMSincormsionre-enhare:(l)thenon-deStrutivechateroftheteCboqUe;(2)possibilltyforquali-tativeandqUanitativephaanalsis;(3)uSehassinidenificationofPOOrlycrystal-lizedoramorphouscormsionpnhats.WththedeVfoPmntofInarineresomees,InansteelconstrUctionswerebulltatsea'MSwasusedforanalfongcormsion~t…  相似文献