SDP and LP fluctuations observed along the coast of Sagami Bay     

Yujiro Kitade  Masaji Matsuyama  Shizuo Iwata  Isao Watabe 《Journal of Oceanography》1998,54(4):297-312

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渤海、黄海、东海M₂潮汐潮流的三维数值模拟   总被引：23，自引：2，他引：21  

王凯  方国洪  冯士筰 《海洋学报》1999,21(4):1-13

利用建立的一种新的半隐半显三维数值格式,将渤海、黄海、东海作为一个整体,采用球面坐标系下的三维潮波方程组,考虑了引潮力的作用,数值模拟了渤海、黄海、东海的M₂分潮的潮汐与潮流,结果较好地体现了渤海、黄海、东海M₂分潮的特征.通过比较65个验潮站的实测值与计算值,所得计算结果的振幅差平均为6.4cm,相角差为6.1°,计算与实测符合良好.本文给出的问潮图与Fang于1986年给出的实测占数值综合结果基本一致.对选取的47个测流站,比较了各层潮流调和常数Ucosζ、Usinζ、Vcosη、Vsinη的计算值与实测值的偏差,偏差绝对值的平均在2.6～4.9cm/s之间.并比较分析了潮流的垂直结构,所得结果与实测符合较好.首次揭示出回流点的水平位置不随深度变化这一特性.最后给出了M₂分潮的潮能消耗.  相似文献   

A Lagrangian mean theory on coastal sea circulation with inter-tidal transports I. Fundamentals   总被引：3，自引：1，他引：2  

FENG Shizuo  JU Lian  JIANG Wensheng 《海洋学报(英文版)》2008,27(6):1-16

A brief review is made on the theory of the Lagrangian residual circulation and inter-tidal transports in a convectively weakly nonlinear system. In the review the emphasis is put on the systematical development of the theory and its weakness of convectively weakly nonlinear approximation. The fundamentals of a Lagrangian tidally-averaged theory on circulation with inter-tidal transport processes have been proposed for a general nonlinear coastal/estuarine system. The Lagrangian residual velocity is strictly de- fined, and it has been verified to be able to embody the velocity field of circulation. A new concept of the concentration for inter- tidal transport processes is presented. The concentration describing the inter-tidal transport processes should be a ＂Lagrangian inter-tidal concentration＂ defined and named, but not the Eulcrian tidally-averaged concentration used traditionally. The circulation described here contains a set of infinite temporal-spatial fields of velocity/concentration, each of which corresponds to a specific value of tidal phases varying continuously over one tidal cycle. When the convectively weakly nonlinear condition（ with a smaller order of eddy diffusion and sources） is approximately satisfied, a set of infinite temporal-spatial fields of velocity/concentration can be reduced to a single one.. the mass transport velocity/the Eulerian tidally averaged concentration as exhibited traditionally.  相似文献   

The baroclinic residual circulation in shallow seas     

Feng Shizuo  Xi Pangen  Zhang Shuzhen 《中国海洋湖沼学报》1984,2(1):49-60

There are two different modeling approaches which have been proposed and utilized to derive residual currents: the first approach is equivalent to deducing residual currents from current-meter records using filtering techniques or time averages of time-series records to remove tidal variations; in the second approach, filters or time averages over several tidal cycles are applied to the hydrodynamic equations to generate the governing equations for residual circulation. Based on the latter, both the baroclinic dynamic models of residual circulation are proposed, of which one is a two-dimensional transport model and the other is a three-dimensional model with variable eddy viscosity. The two-dimensional transport model is a direct generalization from the barotropic model of residual circulation presented by Nihoul and Randy (1975) and Heaps (1978) to the baroclinic model. In the three-dimensional model with variable eddy viscosity, using a Sturm-Liouville system adopted in the reference [5], the nondimensional problem for residual circulation reduces to the nondimensional problem of the elevation and the expression of residual currents. It should be pointed out that both the baroclinic models developed in the present paper are confined to describe the Eulerian residual circulation only.  相似文献   

定性数学的若干基本特征     

管玉平  冯士笮  丑纪范  孙德田 《中国海洋大学学报(自然科学版)》1996,(4)

讨论了几个人工智能中的数学特征以及与传统数学的区别，给出了智能定性模拟的数学基础——定性数学的若干基本运算法则和常用表示方法，该方法对处理某些大气和海洋学问题具有广泛的应用前景  相似文献   

Methane in the western North Pacific   总被引：7，自引：0，他引：7  

Shuich Watanabe  Naoto Higashitani  Nobuo Tsurushima  Shizuo Tsunogai 《Journal of Oceanography》1995,51(1):39-60

The concentration of methane in about 400 seawater samples collected in the western North Pacific, mostly from 40°N to 5°S along 165°E was determined. While the concentration of methane in the surface water was slightly greater in the high-latitudes, it did not widely vary with a standard deviation of 0.29 n mol/l for a mean value of 2.49 n mol/l. The 90% confidence limit of the mean was 0.08 n mol/l. The degree of oversaturation in 1991 (31±4%) was not different from that in circa 1970. If we assume that this degree of oversaturation occurs in the entire oceans, the annual flux of methane becomes 6×10¹²g CH₄. Both the concentrations of methane and chlorophylla were higher in the surface 100 m layer. However, the correlation between them was not well in the entire surface waters. This may indicate that the production of methane is not directly related to the photosynthetic process. The concentration of methane decreased gradually with increasing depth down to 1000 m. Its horizontally and vertically uniform concentration in the abyssal water suggests that the turnover time of methane in the oxic pelagic water is in the range between a few years and a few hundred years.  相似文献   

齐次湍流动能输运方程封闭模型在浅海动力学中的应用     

魏皓  冯士  武建平  刘桂梅 《中国海洋大学学报(自然科学版)》2001,31(6):821-827

该文对已建立的齐次湍流动能输运方程封闭模型 (HKE)封闭的浅海动力学模型进行了检验。湍流混合强度的垂直分布会影流速剖面 ,在风海流、狭长渠道稳态风潮及渠道振荡流流场等的模拟中 ,HKE封闭均取得满意效果 ,结果表明 HKE封闭在正压浅海动力学中是有效的 ,可避免混合长理论的缺陷 ,并未过多增加计算量。振荡流的湍流粘性系数的时间分布特性是时变的 ,其变化频率为振荡频率的两倍 ,且在流速变化最大时湍流混合最强。对应于浅海潮波系统 ,平潮和停潮时局地混合最弱 ,因而最适宜水质采样 ,反之 ,涨急和落急时刻湍流混合最强。但当取湍动能的Schmidt数 σk>10时 ,湍粘性系数的振幅仅为其平均值的 15 % ,因此可以认为在 15 %误差内振荡流的粘性系数可用一个时间平均值来代表  相似文献   

Surface circulation in Sagami Bay: the response to variations of the Kuroshio axis     

Shizuo Iwata  Masaji Matsuyama 《Journal of Oceanography》1989,45(5):310-320

In order to study the characteristics of the surface circulation in Sagami Bay, long-term current measurements were carried out at five moored stations during the period from October 1982 to January 1984. The majority of current patterns show the existence of a cyclonic eddy in the bay, while at times the direction of the circulation is reversed. When the Kuroshio current flows over the Izu-Ogasawara Ridge and approaches Sagami Bay, the current that passes through the Oshima-West Channel north of Oshima Island (COWC), has a strong clockwise flow, while the counterclockwise circulation in the bay becomes intensified. When the Kuroshio shifts southward off the shore, the COWC and the flow in the bay are weak or at times reverse their directions.  相似文献   

Seasonal and areal variation of continental aerosol in the surface air over the western North Pacific region   总被引：1，自引：0，他引：1  

Shizuo Tsunogai  Toshitaka Suzuki  Takayoshi Kurata  Mitsuo Uematsu 《Journal of Oceanography》1985,41(6):427-434

Weekly aerosol samples were collected for two years from 1981 at six stations in the western North Pacific region. The samples were analyzed for aluminum to determine the mineral dust concentration in the air. By combining our data with observations in the central and eastern North Pacific by a US research group, the following results and conclusions have been obtained. Spring peaks in atmospheric mineral dust were observed at all the stations accompanied byKosa episodes (hazes due to mineral dust of Chinese origin). The spring peaks, however, varied from year to year. The mean concentration of mineral dust depends not only on the distance from the Asian coast but also on the latitude of the sampling station. The half-decrease distance of the atmospheric mineral dust turned out to be 500–600 km for all latitudes in the western North Pacific. This indicates that the rate of deposition of mineral dust in the western North Pacific is much larger than that in the central and eastern North Pacific.  相似文献   

赤道深层射流对深层浮力源响应解之特征的分析     

吴德星  冯士莋 《海洋与湖沼》1995,26(6):650-657

基于赤道深层射流动力模型，研究赤道深层射流对深层浮力源的响应特征，指出线性、连续层化海洋中浮力源驱动下的单一垂直模态建立深层环流的过程等介于线性浅水系统中深水源驱动的深层环流的建立过程。分析赤道深层射流对深层浮力源响应解的某些特征，结果表明，在给定确定波数量值的诸参数下，浮力源在纬向上范围的大小对赤道深层的射流  相似文献