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1.
1988—2010年中国海大浪频率及其长期变化趋势   总被引:2,自引:0,他引:2  
利用数值模拟海浪数据,对1988—2010年期间中国海的大浪频率及其长期变化趋势进行较为精细化的统计分析.结果表明:1)近23年期间,中国海的大浪频率基本在30%以内,其中渤海、黄海中北部海域、东海西部近岸海域、北部湾、泰国湾的大浪频率在3%以内,高频海域分布于台湾岛以东广阔洋面、南海中部的东北—西南走向海域.2)春季大浪频率为全年最低,由春季至冬季大浪频率整体上是逐渐递增的.冬季大浪频率为全年最高,大值区为吕宋海峡至中南半岛东南海域一线,呈东北—西南走向的带状分布.3)近23年期间,中国海的大浪频率整体上以0.257%a-1的速度显著性逐年线性递增,且变化趋势表现出较大的区域性和季节性差异.4)不同海域大浪频率的变化趋势由不同季节占主导.  相似文献   

2.
尹兵  于中华 《科技信息》2013,(2):408-409
本文利用来自NASA的CCMP风场资料、来自ECMWF(欧洲中期天气预报中心)的ERA-40海浪资料、来自NOAA的SST资料,对南海-印度洋海域的风、浪、海温等海洋水文要素的季节特征进行了深入统计分析,为防灾减灾、海洋水文保障等提供参考。研究发现:(1)该海域海表风速的最强区域是南印度洋西风带,年平均风速在8-11m/s,北印度洋存在三个大值区:索马里附近海域、孟加拉湾、南海,海浪场分布特征与风场分布特征一致。(2)南印度洋6级以上大风出现频率整体高于北印度洋;北印度洋存在3个6级以上大风的相对高频海域:索马里附近海域、孟加拉湾、南海。2.5m以上波高出现的频率与6级以上大风出现频率的分布特征大体一致。(3)该海域的SST表现出较大的季节性差异。  相似文献   

3.
为了展现印度洋的海浪特征,利用来自欧洲中期天气预报中心的ERA-40海浪再分析资料,对印度洋的海表风场、风浪、涌浪、混合浪场进行研究,主要分析了季节特征、月变化特征、风速和波高的变化趋势、涌浪指标,定义了南印度洋西风指数和涌浪北伸脊点。结果表明:印度洋的风浪场与海表风场整体上对应较好,尤其是季风期间的北印度洋,涌浪场与混合浪场对应较好;从波高来看,阿拉伯海在1-5月和9-12月的涌浪以及孟加拉湾全年的涌浪对混合浪的贡献大于风浪;印度洋海表风速呈显著递增的区域主要集中在咆哮西风带和30°S以北,风浪波高变化趋势的分布与风速大体一致,大部分海域的涌浪波高、混合浪波高表现显著性逐年递增;印度洋的涌浪在混合浪中占据主导地位,40°S以北的涌浪常年向北传播,且南印度洋西风带西南季风的强度直接决定着涌浪北传的程度。  相似文献   

4.
利用1958—1998年NCAR/NCEP再分析资料和美国海军联合台风警报中心JTWC(Joint Typhoon Warning Center)提供的同时期南亚边缘海域(包括阿拉伯海、孟加拉湾和南海)热带气旋资料,分析了这3个海域热带风暴高发期气候上100hPa和850hPa风矢量特征,以及100hPa纬向风强度分别与这3个海域热带气旋年频次之间的关系。结果表明:在阿拉伯海及孟加拉湾热带气旋生成数与100hPa东风气流强度之间存在极好的正相关关系,即东风气流加强热带气旋数目增多,反之减少。而南海由于位于南亚高压东南侧,经向风的显著地位使南海热带气旋与100hPa经向风强弱变化有联系而与纬向风的关系减弱。  相似文献   

5.
台风纵横谈     
谢在永 《科技潮》1998,(8):43-43
台风是发展强烈的气旋,在太平洋、大西洋和印度洋等热带海洋上都可见到它们的足迹。全球每年平均生成台风约80个,其中北半球发生的台风占全球总数的73%。台风集中出现在下述的8个海域:西北太平洋《包括南海》——年均有近30个台风生成,占全球总教的38%,最多年1967年达40个,最少年1951年为20个;东北太平洋——平均有144个台风生成,占全球总数的17%;北大西洋(包括加勒比海和墨西哥湾)每年有9个台风生成;孟加拉湾和阿拉伯海——每年分别有4个和1个台风生成;西南印  相似文献   

6.
亚洲热带边缘海包括阿拉伯海、孟加拉湾、南海和西北太平洋。文中利用美国海军联合台风警报中心JTWC(Joint Typhoon Warning Center)提供的1979—2002年南亚热带边缘海域热带气旋资料和同时期NCAR/NCEP海表温度资料分析了热带气旋生成的纬度趋势。结果:伴随海温的升高,阿拉伯海、孟加拉湾和南海的热带气旋生成最低纬度和平均纬度都有减小的趋势;西北太平洋的热带气旋生成纬度还有增大的趋势;对应低纬海温年际升高,热带气旋生成纬度有减小的年际振荡。  相似文献   

7.
利用1958-1998年NCAR/NCEP再分析资料和美国海军联合台风警报中心JTWC (Joint Typhoon Warning Center)提供的同时期南亚边缘海域(包括阿拉伯海、孟加拉湾和南海)热带气旋资料,分析了这3个海域热带风暴高发期气候上100hPa和850hPa风矢量特征,以及100hPa纬向风强度分别与这3个海域热带气旋年频次之间的关系。结果表明:在阿拉伯海及孟加拉湾热带气旋生成数与100?hPa东风气流强度之间存在极好的正相关关系,即东风气流加强热带气旋数目增多,反之减少。而南海由于位于南亚高压东南侧,经向风的显著地位使南海热带气旋与100hPa经向风强弱变化有联系而与纬向风的关系减弱。  相似文献   

8.
亚洲热带边缘海包括阿拉伯海、孟加拉湾、南海和西北太平洋.文中利用美国海军联合台风警报中心JTWC(Joint Typhoon Warning Center)提供的1979-2002年南亚热带边缘海域热带气旋资料和同时期NCAR/NCEP海表温度资料分析了热带气旋生成的纬度趋势.结果:伴随海温的升高,阿拉伯海、孟加拉湾和南海的热带气旋生成最低纬度和平均纬度都有减小的趋势;西北太平洋的热带气旋生成纬度还有增大的趋势;对应低纬海温年际升高,热带气旋生成纬度有减小的年际振荡.  相似文献   

9.
2003年夏季江淮特大暴雨成因分析   总被引:3,自引:0,他引:3  
利用全球NCEP/NCAR资料,采用诊断分析方法,对2003年夏季6月29日~7月4日发生在淮河流域的特大暴雨过程成因进行了分析,结果表明:暴雨出现与大气环流异常以及水汽输送、西南季风的异常偏强有关;暴雨区的水汽来源于阿拉伯海至孟加拉湾及北太平洋至中国南海地区。  相似文献   

10.
利用1949—2015年CMA-STI热带气旋(TC)的最佳路径数据集分析了影响南海及其不同区域的TC频数、强度、源地和路径等气候特征.结果表明:影响南海、南海北部、南海南部热带气旋的年平均频数分别为11个、7.5个和3.0个,其年变化均为单峰型,峰值月分别出现在9月、8月和11月;影响南海中部的TC的年平均频数为6.1个,其年变化为双峰型,主峰出现在10月,次峰出现在7月.在影响南海的TC中,有52%的TC来源于西北太平洋,48%的TC来源于南海;在影响南海北部、中部和南部区域的TC中,来源于西北太平洋的TC频数占比分别为52%、52%、54%,并且西北太平洋生成的TC强度明显强于南海生成的TC强度.在南海的不同区域中,影响南海北部区域的TC强度最强,南部区域最弱.对于影响南海区域的TC,其生成源地主要集中在5°N以北的南海海域和菲律宾以东至150°E和6°~16°N的西太平洋海域;对于影响南海北部到南部区域的TC,其生成源地的纬度依次向南移、经度依次向西移.对于影响南海及其北部、中部和南部区域的TC,其路径移动方向分别集中在WSW-NW、W-NW、W-NW、WSW-WNW扇区,累计频率均在55%以上,对于主导方向,除南部为W方向(频率23.9%)外,其他均为WNW方向(频率均在24%以上).1949—2015年期间,影响南海和南海北部的TC年频数呈显著的减少趋势,减少速率分别达到0.6个/10a和0.5个/10a,南海中部区域的TC年频数呈微弱的减少趋势,而南部区域的TC年频数则无变化趋势.影响南海及其北部和中部区域的TC强度均有显著增强的趋势,而影响南海南部的TC强度则仅有弱的增强趋势.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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