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1.
Ａｎａｌｔｅｒｎａｔｉｎｇｄｉｒｅｃｔｉｏｎｉｍｐｌｉｃｉｔ（ＡＤＩ）ｎｕｍｅｒｉｃａｌｍｏｄｅｌｆｏｒｔｗｏ－ｄｉｍｅｎｓｉｏｎａｌｈｙｄｒｏｄｙｎａｍｉｃｅｑｕａｔｉｏｎｓ￥ＰａｎＨａｉａｎｄＦａｎｇＧｕｏｈｏｎｇ（ＲｅｃｅｉｖｅｄＤｅｃｅｍｂｅ... 相似文献
2.
Three-dimensional hydrodynamic model of Xiamen waters 总被引：3，自引：0，他引：3
Abstract-A semi-implicit and Eulerian-Lagrangian finite difference method for three-dimensionalshallow flow has been extended to a more complete system of equations incorporating second-momentturbulence closure model and transport equations of salinity and temperature. The simulation for flood-ing and drying of mudflats has been improved. The model is applied to Xiamen waters. Based on exten-sive survey data, water level elevation, temperature and salinity field along the eastern open boundaryand at the Jiulong River inlets and runoffs are analyzed, specified and calibrated. The computed resultsshow good agreement with the measured data, reproduce flooding, emergence of large and complexmudflat region. 相似文献
3.
This is second paper summarizing the study on the hydrous titanium oxide absorbent for extracting uranium fromseawater. The investigation is performed by means of X- ray photoelectronic energy spectroscopy for chemical analysis ( ESC A ) , determination of surface hydroxy radical, Fourier-transfer infrared spectrophotometry (FT-IR ) , electron paramagnetic resonance (EPR), inductively coupled Plasma torch (ICP), etc. The emphasis is laid upon the exploration of HTO surface and a discussion about the adsorption micromechanism. 相似文献
4.
The Dirichlet–Neumann operator for the water-wave problem was introduced and expanded by Craig and Sulem [Craig, W., Sulem, C., 1993. [CS] Numerical simulation of gravity waves. J. Comput. Phys. 108, 73–83] and in a slightly different form and for 3D waves by Bateman, Swan and Taylor [Bateman, W.J.D., Swan, C., Taylor, P.H., 2001. [BST] On the efficient numerical simulation of directionally spread surface water waves. J. Comput. Phys. 174, 277–305]. This approach is supposedly superior to techniques derived earlier by West et al. [West, B.J., Brueckner, K.A., Janda, R.S., Milder, D.M., Milton, R.L., 1987. [WW] A new numerical method for surface hydrodynamics. J. Geophys. Res. 92 (C11), 11803–11824] and Dommermuth and Yue [Dommermuth, D.G., Yue, D.K.P., 1987. [DY] A high-order spectral method for the study of nonlinear gravity waves. J. Fluid Mech. 184, 267–288] under seemingly more restrictive assumptions. This paper extracts the Dirichlet–Neumann operator expansions from West et al. and Dommermuth and Yue. Concerning the operator expansions alone it is found that Bateman et al. is identical to West et al. and Dommermuth and Yue while Craig and Sulem is slightly different due to minor differences in the operator definition. For application to the free-surface boundary conditions West et al. devised a consistent truncation at nonlinear order. This alters the equivalence of the different approaches when it comes to the evaluation of the temporal derivative of the free surface elevation, which is decisive for wave evolution. In this regard Craig and Sulem is found to be identical to West et al. while Bateman et al. is identical to Dommermuth and Yue. Pseudo code is provided for alternative computational schemes in Fourier-space and physical space, respectively, along with a discussion of efficiency and potential flexibility. 相似文献
5.
Probability distribution of surface slope for nonlinear random sea waves and calculation of whitecap
《海洋学报(英文版)》1997,(2)
Ｂａｓｅｄｏｎｔｈｅｎｏｎｌｉｎｅａｒｍｏｄｅｌｏｆｔｗｏ－ｄｉｍｅｎｓｉｏｎａｌｒａｎｄｏｍｓｅａｗａｖｅｓ，ａｓｔａｔｉａｔｉｃａｌｄｉｓｔｒｉｂｕｔｔｔ崳铮睿铮妫鳎幔觯澹螅酰颍妫幔悖澹螅欤铮穑澹澹幔悖簦簦铮簦瑁澹簦瑁椋颍洌铮颍洌澹颍椋螅洌澹颍椋觯澹洌猓酰螅椋睿纾簦瑁澹澹穑幔睿螅椋铮睿铮妫簦瑁澹悖瑁幔颍幔悖簦澹睿螅簦簦椋悖妫酰睿悖簦簦铮睿幔睿洌洌椋颍澹悖簦悖幔欤悖酰欤幔簦椋铮睿螅铮妫澹幔悖瑁铮颍洌澹颍恚铮恚澹睿簦拢幔螅澹洌铮睿簦瑁澹洌椋螅簦颍椋猓酰簦椋铮睿铮妫鳎幔觯澹螅酰颍妫幔悖澹螅欤铮穑澹洌澹颍椋觯澹洌椋睿簦瑁椋螅穑幔穑澹颍幔鳎瑁椋簦澹悖幔穑悖铮觯澹颍幔纾澹恚铮洌澹欤椋螅穑颍铮穑铮螅澹洌猓酰螅椋睿纾簦瑁澹欤椋恚椋簦螅酰颍妫幔悖澹螅欤铮穑澹幔螅幔悖悖椋簦澹颍椋铮睿铮妫鳎幔觯澹猓颍澹幔耄椋睿纾裕瑁澹鳎瑁椋簦澹悖幔穑悖铮觯澹恚纾澹澹穑颍澹螅螅澹洌猓觯簦瑁澹恚铮洌澹欤洌澹穑澹睿螅铮睿簦瑁颍澹澹穑幔颍幔恚澹簦澹颍螅鳎瑁椋悖瑁悖幔睿猓澹洌澹簦澹颍恚椋睿澹洌椋睿穑颍椋睿悖椋穑欤澹猓簦瑁澹欤椋睿澹幔颍鳎幔觯澹螅穑澹悖簦颍酰恚幔睿洌簦瑁颍澹澹耄椋睿洌螅铮妫鳎幔觯澹鳎幔觯澹椋睿簦澹颍幔悖簦椋铮睿 相似文献
6.
Based on the nonlinear model of two-dimensional random sea waves, a statistical distribution of wave surface slope exact to the third order is derived by using the expansion of the characteristic function and direct calculations of each order moment. Based on the distribution of wave surface slope derived in this paper, a whitecap coverage is proposed by using the limit surface slope as a criterion of wave breaking. The whitecap coverage expressed by the model depends on three parameters which can be determined in principle by the linear wave spectrum and three kinds of wave-wave interaction. 相似文献
7.
In the asymmetric and symmetric nonlinear--metal--nonlinear dielectric structures, this paper studies the analytic dispersion relation for surface plasmon in a system consisting of a thin metallic film covered on two sides media of intensity-dependent refractive indexes by applying a generalised first integral approach. Especially in the symmetric waveguide structure, two possible modes can exist: the odd mode and the even mode. The dispersion relations of the two modes are obtained. Due to the nonlinear dielectric, the squared magnitude of the electric field at the interface appears and alters the dispersion relations. Numerical results are compared to those from a certain approximate treatment. 相似文献
8.
The 25-h measurements of current speed, flow direction, water depth, suspended sediment concentration and salinity were carried out at six anchored stations in the study area during spring and neap tides in winter of 1987 and summer of 1989. Caculations and analyses of the data obtained show that large amounts of suspended sediments are moved back and forth under the action of tidal current, and the net transport of sediment is small, with its predominance upstream in winter and downstream in summer. These calculations and analyses also suggest that the advective transport of sediment is dominant, while the vertical gravitational circulation of the suspended sediment comes next. Meantime, it is indicated that tidal currents play a major role in the suspended sediment transport, and residual flows have effect on the net transport of the suspended sediment, which is more remarkable during neap tide than during spring tide. 相似文献
9.
Information about short-wavelength (from 0.2 to 4 μm) heat radiation fluxes incoming to the ocean surface is available from very few observations collected by shipboard equipment and buoys and obtained from satellite data archives. Presently, the most complete archive on short-wavelength radiation fluxes is provided by geostationary Earth-orbiting satellites, such as 1G and 2G МETEOSAT (European Union), GOES (United States) and HIMAWARI (Japan), which are equipped with scanners operating in the visible and infrared (IR) ranges, which can image the Earth’s disk every 0.5 h. Additionally, the European EPS/MetOP satellites and US NOAA satellites circulating in mid-altitude circumpolar Sun-synchronous orbits and carrying AVHRR radiometers [1] can be used to obtain daily and monthly average values of incoming short-wavelength solar radiation fluxes. In the future, radiation heat flux data measured by satellites will undoubtedly play a leading role; however, today, the available data record spans only the last few decades, still lacking accuracy and consequently requiring thorough validation. 相似文献
10.
Back-scattering from rough sea surface with foams 总被引：2，自引：0，他引：2
INTRODUCTION Eleetromagnetie baek一seattering from randomly rough surfaee driven by wind,and funetion-al dePendenee on wind sPeed and direetion,and the eharaeteristie Parameters of sea surfaee havebeen interested in the ocean remote sensing.One of the approaehes to eleetromagnetie seatteringfrom randomly rough surfaee 15 the Kirehhoff approximation(KA),and the geometrie opties 50-lution in high frequeney 15 used by the stationary phase method(Bass and Fueks,1979) .TheKA solution 15 val… 相似文献
11.
The fractal characteristic change in the Huanghe River Estuary due to the hydrodynamic conditions'' variation 总被引：4，自引：0，他引：4
Abstract-The study area lies in the subaqueous delta, which came into being in 1964～1976. Oneoil-field road has been built for exploring petroleum to form a wave barrier. The hydrodynamic conditionson the north side of the road are relatively violent, on the contrary the hydrodynamic conditions on thesouth side of the road are nearly placid. This makes the study area a natural laboratory for studying theinfluence of the hydrodynamic conditions on the fractal characteristics of the tidal flat. Selecting an areais named Case Ⅰ on the side of stronger hydrodynamic activities and an area is named Case Ⅱ on the otherside. Measuring the topography and sampling and analyzing the granulometrical comoposition, it is foundthat the hydrodynamic conditions have fatal influence on the surface fractal dimensions and the granulo-metrical fractal dimensions of the area. In Case Ⅰ, which has strong hydrodynamic conditions, the sur-face fractal dimensions are obviously large than those of Case Ⅱ, and the granulometr 相似文献
12.
Trends of sea surface temperature and sea surface temperature fronts in the South China Sea during 2003–2017 总被引：2，自引：0，他引：2
The trends of the sea surface temperature(SST) and SST fronts in the South China Sea(SCS) are analyzed during2003–2017 using high-resolution satellite data. The linear trend of the basin averaged SST is 0.31°C per decade,with the strongest warming identified in southeastern Vietnam. Although the rate of warming is comparable in summer and winter for the entire basin, the corresponding spatial patterns of the linear trend are substantially different between them. The SST trend to the west of the Luzon Strait is characterized by rapid warming in summer, exceeding approximately 0.6°C per decade, but the trend is insignificant in winter. The strongest warming trend occurs in the southeast of Vietnam in winter, with much less pronounced warming in summer. A positive trend of SST fronts is identified for the coast of China and is associated with increasing wind stress. The increasing trend of SST fronts is also found in the east of Vietnam. Large-scale circulation, such as El Ni?o, can influence the trends of the SST and SST fronts. A significant correlation is found between the SST anomaly and Ni?o3.4 index, and the ENSO signal leads by eight months. The basin averaged SST linear trends increase after the El Ni?o event(2009–2010), which is, at least, due to the rapid warming rate causing by the enhanced northeasterly wind. Peaks of positive anomalous SST and negatively anomalous SST fronts are found to co-occur with the strong El Ni?o events. 相似文献
13.
14.
1 IntroductionThe variability of the air -sea system orches-trates a complex climate system of our earth, andthis variability gives rise to an array of naturally oc-curring dynamical modes at different time scales.These modes are important attributes of c… 相似文献
15.
Here in present work, rotational Boussinesq–Green–Naghdi models were applied to assess the hydrodynamic intensity through the study of the boulder transport in east coast of Philippines during typhoon Haiyan and damage to coastal residences in New Jersey coast due to hurricane Sandy. The hydrodynamic forces were quantitatively analyzed and correlated to both boulder transport distance and the structural damage state in the two cases. The boulder transport was found initiated at vicinity of infragravity swash bores. Inertial force generated by the acceleration in front of the bore was found increasingly large as boulder sizes increased therefore far from negligible as in some other literatures. Besides, transport distances were highly sensitive to wave-heights and boulder sizes, so that onshore positions might be a viable approach of identifying rough magnitudes of paleostorm before other information is available. Fragility functions to predict the damage state of coastal residences due to runups was derived and preliminary validated. Water velocity and the shielding parameter were identified as major predictors of damage while free board and water depth are relatively insignificant. Due to the relative lack of wind damage observed, nearshore hydrodynamics featuring instantaneous nonhydrostatic impact might be the persistent cause of massive littoral processes and low-level structural failure in coastal regions during extreme marine events. Nonhydrostatic phase-resolving models such as Boussinesq-type models would be necessary complements for the intermediate-scale assessment of marine hazards in coastal ocean. 相似文献
16.
In this paper the stochastic Green function method is used to solve random wave equation of the electromagnetic field. The volume scattering coefficient formula of the sea surface containing bubbles is given. It is also point out that when the incident angle of the electromagnetic wave is less than 30°, the surface scattering model is not sufficient. The joint problem of the volume scattering and the surface scattering coefficient in the neighbourhood of incident angle 30° is discussed. 相似文献
17.
In this paper, a nonsteady atmosphere-earth surface coupled anomaly model is used to conduct both comparative experiments on the physical processes of model and monthly forecasting experiments for anomaly fields. It is shown that after further improvement it is hopeful for the anomaly model with two-hour time step to do monthly forecasting of anomaly fields by taking long period time integration. The comparative experiments show that the interaction between the atmosphere and the surface has significant influence on the long range variation for both atmospheric geopotential anomalies and surface temperature anomalies, and transient eddy transport has also certain effects on the variation of anomaly fields. 相似文献
18.
V. N. Aref’ev F. V. Kashin L. I. Milekhin V. L. Milekhin N. V. Tereb L. B. Upenek 《Izvestiya Atmospheric and Oceanic Physics》2013,49(1):66-76
The results of measurements of surface ozone in central European Russia in 2004–2010 are presented. The variation coefficient for hourly, monthly, and annual mean ozone concentrations is 78, 26, and 12%, respectively. The measurements established a link between increased (>60 μg/m3) and minimum (<12 μg/m3) hourly mean ozone concentrations with the existence of a temperature inversion in the lower 300-m atmospheric layer. Sixty-seven percent of the total number of increased hourly mean ozone concentrations over the 2004–2010 period took place in 2010. A maximum hourly mean ozone concentration of 218.5 μg/m3 was recorded at 17:00 on August 1, 2010. The annual mean ozone concentration in a climatically significant range of hourly mean concentrations from 12 to 60 μg/m3 increased by 45% in a linear approximation over the period of record. The spectral analysis of monthly mean concentrations of surface ozone identified composite oscillations with periods from 3 to 60 months. To approximate the temporal dynamics of ozone, a statistical model was used. This model satisfactorily describes the experimental monthly and annual mean concentrations. 相似文献
19.
LU Xiaoxi SONG Jinming LI Xuegang YUAN Huamao ZHAN Tianrong LI Ning GAO Xuelu 《海洋学报(英文版)》2004,23(3):473-482
The distributions of different forms of nitrogen in the surface sediments of the southern Huanghai Sea are different and affected by various factors. The contents of IEF-N, SOEF-N and TN gradually decrease eastward, and those of SAEF-N northward, while those of WAEF-N westward. Around the seaport of the old Huanghe (Yellow) River, the contents of both SOEF-N and TN are the highest. Among all the factors, the content of fine sediment is the predominant factor to affect the distributions of different forms of nitrogen. The contents of IEF-N, SOEF-N, and TN have visibly positive correlation with the content of f‘me sediments, and the correlative coefficient is 0.68, 0.58 and 0.71 respectively, showing that the contents of the three forms of nitrogen increase with those of f-me sediments. The content of WAEF-N is related to that of fine sediments to a certain extent, with a correlative coefficient of 0.35; while the content of SAEF-N is not related to that of fine sediments, showing that the content of SAEF-N is not controlled by fine grain-size fractions of sediments. In addition, the distributions of different forms of nitrogen are also interacted one another, and the contents of IEF-N and SOEF-N are obviously affected by TN, while those of inorganic nitrogen (WAEF-N, SAEF-N and IEF-N) are not affected by SOEF-N and TN obviously, although they are interacted each other. 相似文献
20.
By using the atmosphere-ocean coupled model (CGCM) which is composed of a 2-level global atmospheric general circulation model and a 4-layer Pacific oceanic general circulation model developed in the Institute of Atmospheric Physics of Chinese Academy of Sciences, and two model climatological fields got from the two independent models' numerical integrations respectively, the Pacific sea surface temperature anomalies (SSTA) from 1988 to 1989 are simulated in this paper with observed atmospheric general circulation data and sea surface temperature fields as initial conditions and monthly coupling scheme. In order to remove systematic biases of the model climatological fields, interaction variables between atmosphere and ocean are also corrected simultaneously. The experiments show that the simulation results can be improved effectively if these interaction variables are corrected in spite of the fact that there always exist systematic biases in independent numerical simulations of atmospheric part and oc 相似文献