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1.
利用印度气象局（India Meteorological Department,IMD）、国际气候管理最佳路径档案库（International Best Track Archive for Climate Stewardship,IBTrACS）提供的1982—2020年阿拉伯海热带气旋路径资料,美国国家环境预报中心（National Centers for Environmental Prediction,NCEP）再分析资料,对近39 a阿拉伯海热带气旋源地和路径特征、活跃区域、频数及气旋累积能量（accumulated cyclone energy,ACE）指数的季节特征和年际变化特征进行分析,并结合环境因素,说明其物理成因。结果表明：阿拉伯海热带气旋多发于10°~25°N,65°~75°E海域,5—6月、9—12月发生频数较高且强度较强,1—4月、7—8月发生频数较低且气旋近中心最大风速均小于35 kn;频数的季节变化主要受控于垂直风切变要素;阿拉伯海热带气旋发生频数和ACE近年有上升趋势,年际变化主要受控于海面温度（sea surface temperature,SST）和850 hPa相对湿度要素。 相似文献
2.
我国近海热带气旋活动的气候特征及其与大尺度环境场的关系 总被引：4，自引：0，他引：4
利用1949~2004年共54 a的热带气旋资料,通过对历年影响我国近海(距海岸线300 n mile范围内)25°N以北及以南热带气旋的基本要素特征值的分析,发现我国近海25°N以北与以南热带气旋影响的频数和年代际变化不一致,尤其是20世纪80年代中期以来呈现反位相特征,近海25°N以北TC偏多,强度强;25°N以南TC偏少,强度弱.对热带气旋个数偏多年与偏少年对应的夏季海温场、高度场的合成分析,发现25°N以北偏多年比以南偏多年的东太平洋海温负距平强度大、范围广,高度距平场上反映出25°N以北偏多年西太平洋(包括南海)负高度距平区更为偏北、偏东;25°N以北TC偏少年时,中东太平洋海温为正距平区,高度场上太平洋低纬区域基本为正距平区,太平洋高纬区域是负距平区,而以南TC偏少年中东太平洋海温是负距平区,高度场上太平洋高纬区域是正距平区.文中还对当年前期各月海温场、高度场与当年以北、以南热带气旋个数分别作了相关分析,得出了一些实用有效的预报因子. 相似文献
3.
本文是在过去多种方案的基础上,经提炼、修改、补充就其南海热带气旋从其生成开始到发展阶段,对其移动过程中的具体路径、强度变化及影响的地区范围等方面,按区、类分别研制出一套定性判断和定量预报相结合的客观预报流程,全流程分四个子系统执行。 资料选取（970-1979）十年7—9月份的天气图资料。取样范围为进入10°—23°N, 110°—120°E海区的103个南海热带气旋作样本。并用（1980-1985）六年 11个南海热带气旋作独立样本检验、以鉴定所建方程的稳定性和正确率。从试报效果看,本方案具有一定的预报能力,使客观预报方法在应用于南海热带气旋的多种预报方面,显示它的系统性,并具有一定的实用价值。 相似文献
4.
利用1949~2013年的热带气旋最佳路径和Nino3.4指数资料,探讨了影响福建省的热带气旋数量和强度与ENSO之间的关系.结果表明,影响福建省的热带气旋数目在拉尼娜年要比厄尔尼诺年略偏多.但对于强台风和超强台风级别的热带气旋而言,反而是在厄尔尼诺年偏多,其频数是拉尼娜年的1.5倍.另外,热带气旋发生的高峰期,在拉尼娜年为7~9月,在厄尔尼诺年则为7~10月,即厄尔尼诺年中的高峰期相对较长;同时,在拉尼娜年中,强台风和超强台风的发生时间较厄尔尼诺年的6~9月要迟延1个月左右,为7~10月. 相似文献
5.
台风是一种破坏性极强的自然灾害，我国位于太平洋西岸，是受台风影响最严重的国家之一，因此研究西北太平洋热带气旋路径的分布规律对台风预报有着重要意义。本文利用热带气旋最佳路径数据集资料，研究了1949—2017年间厄尔尼诺年与拉尼娜年发生在西北太平洋的热带气旋的数量及路径分布规律，得出了如下的主要结论：厄尔尼诺年的热带气旋年平均产生数量要少于拉尼娜年，但发展至强度为台风及以上的热带气旋所占比例更高；厄尔尼诺年与拉尼娜年热带气旋路径的分布都主要集中在10～20°N的低纬地区，但厄尔尼诺年的热带气旋路径在菲律宾群岛东侧海域更为集中，拉尼娜年的在菲律宾群岛西侧海域更为集中；强度为台风及以上的热带气旋路径分布规律与所有强度热带气旋路径的分布规律相似，但更偏北一些，尤其在厄尔尼诺年偏北现象更为明显；热带气旋增强区域的分布与热带气旋路径的分布规律基本相同。 相似文献
6.
源自南海东北部海区热带气旋的若干统计特征 总被引：4，自引：0，他引：4
1949－1998年50a中，源自南海东北部海区的热带气旋共67个，其中有17a无热带气旋产生，45a无台风。该海区产生的热带气旋及其有关的统计特征与南海南部和热带西太平洋的热带气旋不同：平均个数是厄尔尼诺年较反厄尔尼诺年少；春季型的厄尔尼诺过程中热带气旋生成较多；1970－1990的的强厄尔尼诺过程中热带气旋个数当年较次年多，1990年后则相反，与历次厄尔尼诺过程比较，1997－1998年特强厄尔尼诺过程中的热带气旋生成较多、发展较快、其异常的气候特征为有史以来所罕见。 相似文献
7.
影响华南沿海的热带气旋分析 总被引：6，自引：0，他引：6
利用１９４９－１９９８年《台风年鉴》和气候与水文资料,对华南沿海的热带气旋作了统计分析,结果表明：登陆华南沿海的热带气旋是厄尔尼诺年较反厄尔尼诺年少,近期厄尔尼诺过程对 旋活动影响尤为明显。登陆各少区热带气旋的年际变化存在明显差异,月际变化是登陆的高峰月份较一致。登陆个数提广东省居多,广西区最少,登陆岸区较集中。影响华南沿海海区的台风,东部海区明显地少于西部海区。５０ａ间,我国台风最大风速和最大增 相似文献
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热带气旋是影响南海地区的主要灾害性天气系统。每年热带气旋频繁地袭击南海,威胁着南海石油平台的正常作业。本文利用1949-1986年间的气候资料,对位于21°10′N,115°50′E的南海石油平台海域的热带气旋的气候学特征进行分析研究,找出热带气旋的源地、强度、频率、移速、移向、季节变化和年变化,大风以及路径分布等气候特征,为石油平台安全作业的海洋水文要素的计算和热带气旋的预报提供有用的气候背景。 相似文献
10.
厄尔尼诺事件与影响粤西的热带气旋 总被引：2，自引：0，他引：2
利用１９５６－１９９７年的热带气旋资料,对厄尔尼诺事件与影响粤西地区的热带气旋进行了统计分析。结果表明;厄尔尔尼诺年影响粤西的热带气旋较常年频繁,厄尔尼诺年则明显少于常年;厄尔尼诺事件的强弱变化与西热带气旋活动的频数明显相关,呈一种反位相的关系。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
14.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
17.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
18.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献
19.
This study tests the hypothesis that the in situ void ratio of surficial marine sediments may be predicted from shear wave velocity-depth data with a reliability equal to that of other methods currently available. Shear wave velocity is fundamentally controlled by the number of grain-to-grain contacts per unit volume of material and by the effective stress across those contacts. In this study, three previously established empirical formulae are used to predict void ratio from velocity-depth data. Field data were acquired along a transect off the northern Californian coast across which water depth increased from 35 to 70 m and seafloor sediment type varied from sand to silty-sand, respectively. A towed seafloor sled device was used to collect shear wave refraction data, and a marked, systematic decrease in velocity was observed along the line, ranging from 35-70 m/s for the coarse, near-shore material to 25-40 m/s for the finer, offshore deposits. Void ratios predicted from these velocities were compared with data measured directly from box-core samples. Of the formulae used for prediction, two agree remarkably well with the control data. Both predicted and control values increase from 0.6-0.8 for the sandy material to 1.1-1.5 for the silty-sand. Thus, this study does not disprove the hypothesis set and demonstrates the potential of field shear wave velocity-depth data as a means of delineating spatial variation in void ratio for surficial marine sediments in a remote, nondestructive manner. 相似文献
20.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ～ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream. 相似文献