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1.
Tidal levels and currents in the Tongan region of the Pacific were simulated using a two-dimensional frequency-domain finite element model. The eight major diurnal and semidiurnal tidal constituents were modeled successfully, using open boundary conditions taken from a global tidal model based on the Topex/Poseidon satellite altimeter. Comparison of model results with observations from the single tide gauge site in the area were later used to adjust the boundary conditions. The validity of omitting horizontal eddy viscosity from the finite element model was checked by running an equivalent finite difference model. The results show that although the submarine Tongan ridge does not appear to trap tidal energy, there are residual tidal currents and possible recirculations which are capable of influencing biological productivity around Tonga. The model results are reduced to a simple method for predicting tidal heights in outlying areas, based only on the tidal calendar for the capital, Nuku'alofa. 相似文献
2.
Tidal levels and currents in the Tongan region of the Pacific were simulated using a two-dimensional frequency-domain finite element model. The eight major diurnal and semidiurnal tidal constituents were modeled successfully, using open boundary conditions taken from a global tidal model based on the Topex/Poseidon satellite altimeter. Comparison of model results with observations from the single tide gauge site in the area were later used to adjust the boundary conditions. The validity of omitting horizontal eddy viscosity from the finite element model was checked by running an equivalent finite difference model. The results show that although the submarine Tongan ridge does not appear to trap tidal energy, there are residual tidal currents and possible recirculations which are capable of influencing biological productivity around Tonga. The model results are reduced to a simple method for predicting tidal heights in outlying areas, based only on the tidal calendar for the capital, Nuku'alofa. 相似文献
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B. B. Ilyushin 《Izvestiya Atmospheric and Oceanic Physics》2014,50(3):246-255
Results of simulating the diurnal evolution of the atmospheric boundary layer (ABL) with a second-order closure model are presented. The model includes new algebraic expressions for triple correlations to describe their behavior over the entire height of the mixed layer adequately to measurements. The model also takes into account the influence of long-wave radiation on the heat balance, which becomes important in the nocturnal ABL. The modeling results are compared with 24-h ABL evolution simulations by the third-order closure model and available in situ and laboratory measurements. 相似文献
5.
The northward migration of spring bloom was observed in the Sea of Japan from April to May 1997 by the Ocean Color and Temperature
Scanner (OCTS) on board the Advanced Earth Observing Satellite (ADEOS). This phenomenon is well simulated with a numerical
ecosystem model coupled with a hydrodynamic model. The hydrodynamic model is the Geophysical Fluid Dynamics Laboratory (GFDL)
Modular Ocean Model (MOM). The ecosystem model consists of five components: dissolved inorganic nitrogen (DIN), dissolved
inorganic phosphorus (DIP), phytoplankton, zooplankton and detritus. Results of the numerical ecosystem model suggest that
the mesoscale development of the spring bloom in the Sea of Japan is related to that of sea water temperature, and that the
bloom is limited by the depletion of DIN.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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采用变分资料同化技术,结合最优控制思想,对一个海气耦合模型的模式参数和强迫项进行了反演,结果表明,采用该方法对模式进行优化,既可以补偿模式参数不准确性给预报带来的误差,又可以对模式参数本身进行修正和估计,为将来在实际应用中改善更复杂的预报模式、提高预报准确率提供了一个可借鉴的思路。 相似文献
7.
The Gulf Stream system has been numerically simulated with relatively high resolution and realistic forcing. The surface fluxes
of the simulation were obtained from archives of calculations from the Eta-29 km model which is an National Center for Environment
Prediction (NCEP) operational atmospheric prediction model; synoptic fields are available every 3 hour. A comparison between
experiments with and without surface fluxes shows that the effect of the surface wind stress and heat fluxes on the Gulf Stream
path and separation is closely related to the intensification of deep circulations in the northern region. Additionally, the
separation of the Gulf Stream and the downslope movement of the Deep Western Boundary Current (DWBC) are reproduced in the
model results. The model DWBC crosses under the Gulf Stream southeast of Cape Hatteras and then feeds the deep cyclonic recirculation
east of the Bahamas. The model successfully reproduces the cross-sectional vertical structures of the Gulf Stream, such as
the asymmetry of the velocity profile, and this structure is sustained along the downstream axis. The distribution of Root
Mean Square (RMS) elevation anomaly of the model shows that the eddy activity of the Gulf Stream is realistically reproduced
by the model physics. The entrainment of the upper layer slope current into the Gulf Stream occurs near cross-over; the converging
cross-stream flow is nearly barotropic.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
A. V. Grigor'ev 《Physical Oceanography》1991,2(2):105-111
The results of numerical experiments involving a dynamic-stochastic model closed at the second moment level are reported. Specific features of the model are the possibility of using it neglecting viscosity coefficients, as well as in energy and enstrophy conservation at the prediction stage. The model is fairly effective in saving computer time. The model prognostic fields are less smoothed than those produced by a model with similar characteristics of the computed grid area and with biharmonic viscosity.Translated by Vladimir A. Puchkin. 相似文献
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A three-dimensional (3-D) coupled physical and biological model was used to investigate the physical processes and their influence on the ecosystem dynamics of the Bohai Sea of China. The physical processes include M2 tide, time-varying wind forcing and river discharge. Wind records from 1 to 31 May in 1993 were selected to force the model. The biological model is based on a simple, nitrate and phosphate limited, lower trophic food web system. The simulated results showed that variation of residual currents forced by M2 tide, river discharge and time-varying wind had great impact on the distribution of phytoplankton biomass in the Laizhou Bay. High phytoplankton biomass appeared in the upwelling region. Numerical experiments based on the barotropic model and baroclinic model with no wind and water discharge were also conducted. Differences in the results by the baroclinic model and the barotropic model were significant: more patches appeared in the baroclinic model comparing with the barotropic model. And in the baroclinic model, the subsurface maximum phytoplankton biomass patches formed in the stratified water. 相似文献
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《Deep Sea Research Part I: Oceanographic Research Papers》2000,47(5):875-899
The region of the North Atlantic between the Azores, the Canary Islands and the Gibraltar Strait is the subject of the multidisciplinary CANIGO project. A fine resolution primitive equation level model, called the CANIGO regional model, has been constructed to help with the integration of the observations. The model has open boundaries on three sides and at the Strait of Gibraltar.The output from the regional model gives a good representation of the Azores Current, the variability around Madeira, the Canary Current and the associated upwelling, the Cape Ghir and other cool filaments, and the spreading of Mediterranean Water. After passing south of the Azores, the Azores Current splits into two branches. The northern branch meanders towards the Gulf of Cadiz and the Gibraltar Strait, and the southern branch passes south of Madeira and through the Canary Archipelago. 相似文献
13.
海洋生态系统中放射性核素转移的数值模拟 总被引：1，自引：0，他引：1
在西大亚湾海域浓度场分布的基础上,用库室模型分析的观点建立了海洋生态系统库室模型,采用浓集因子法建立了相应的线性方程组,对放射性核素在浮游植物、浮游动物、软体动物、甲壳动物、鱼类以及沉积物中的迁移进行数值模拟。数值模拟结果从一定程度上反映了核电站液态排放对海洋生态系统影响的规律。这为预测核电站废水排放对海洋生态系统的影响提供了一套有价值的参考模型及软件。 相似文献
14.
A morphological quasi-three-dimensional (Q3D) area model for barred coasts has been developed. The model combines a two-dimensional depth integrated model for wave-driven currents with a model for undertow circulation currents. The combined model makes a simultaneous simulation of the bar-forming processes associated with the undertow and the horizontal wave-driven circulation currents, which may cause instabilities of the bar and the formation of rip channels. Situations with normal and oblique wave incidence are considered. Compared to the depth integrated approach the Q3D model produces less pronounced alongshore irregularities for obliquely incident waves. For normal incident waves the Q3D model produces a crescentic bar while the depth integrated model predicts almost straight sections of the bar interrupted by rip channels. The sensitivity to variation of wave angle and beach slope is further investigated. 相似文献
15.
Within the EU-funded project HIPOCAS (Hindcast of Dynamic Processes of the Ocean and Coastal Area of Europe), high-resolution wave hindcasts were performed for the period 1958–2001 over the Eastern Mediterranean. The state-of-the-art WAM model was used for producing the 44-year wave data set. The wave model was driven by wind data generated from the regional atmospheric model REMO. The WAM model outputs of significant wave height were validated against in-situ measurements and satellite data. The model results show a good agreement with observations. The homogeneous wave data set produced by the model was then used for a study of long-term variability and climatic trends in the region. 相似文献
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象山港围隔生态系水质模型研究 总被引：1，自引：0，他引：1
在美国环保局开发的WASP(the water quality analysis simulation program,水质分析模拟程序)中的概念模型基础上,运用系统动力学软件Stella9.0.2建立了适用于海洋围隔生态系水质动力学模型.模型包括浮游植物、磷循环、氮循环、碳生化需氧量-溶解氧4个模块,涉及叶绿素a、有机磷、无机磷、有机氮、氨氮、硝酸-亚硝酸盐氮、生化需氧量、溶解氧8个水质指标.利用2010年10月初象山港围隔生态实验数据进行了模型验证和参数率定工作,成功模拟了不同水温条件下围隔水质情况,并确定了30余个模型参数,展现了系统动力学模拟的优势,为揭示象山港海域生态系统的动力学机制,模拟和预测他的变化提供科学依据. 相似文献
17.
蒸发波导是海上大气波导中发生概率最高、对海上舰艇和岸基雷达探测系统影响最大的一种波导类型,研究意义重大。本文搭建了一种基于NPS诊断模型的新型蒸发波导数值预报模式,对我国南海海域2014年11月1~5日的5 d海上蒸发波导分别进行了数值模拟。利用数值模拟数据与岸基铁塔实测数据分别绘制蒸发波导高度随时间的变化曲线,并进行误差分析,显示模拟结果与实测结果变化规律基本一致,统计计算这5 d的蒸发波导高度平均误差为1.289 m。这表明了本模式的可行性及其存在的模拟偏差。此外,利用本预报模式对南海海域2011年整年的蒸发波导进行了数值模拟,得到了12个月的蒸发波导时空分布特征,分析总结的规律与其它文献的研究结论基本一致。 相似文献
18.
A two-zone model of the atmospheric circulation over the hemisphere is considered. The geographic latitude φ of the boundary between the Rossby circulation regime zone at middle and high latitudes and the Hadley circulation regime zone at low latitudes serves as a model variable. The closeness between the actual and reference (exponential) air-mass distribution over the hemisphere, with respect to Ertel’s modified potential vorticity (MPV), is accounted for. The informational entropy of the statistical MPV distribution in the hemispheric atmosphere and the informational entropy of the eddy regime in the basic storm-track zone are used to determine a statistically (climatically) equilibrium value of φ. The question of atmospheric blocking over the hemisphere is considered using the proposed statistical–dynamical model. 相似文献
19.
Cornelis Veth 《Marine Chemistry》1991,35(1-4)
The evolution of the wind-mixed layer and surface temperature in a period of ice retreat is studied with a one-dimensional turbulent erosion model. This model is established to provide values for a number of physical parameters to be used in ecophysiological modelling of plankton blooms in an area with a retreating ice cover. The wind-mixed layer (WML) model is driven by parameters obtained by regular on-board meteorological observations, visual ice cover estimates and global radiation measurements. The results of numerous conductivity-temperature-depth (CTD) casts performed during the EPOS leg-2 cruise provided the data for the initial conditions and validation. 相似文献
20.
Results are described from a limited area barotropic model of the North Pacific with 1/3°×1/3° resolution and bounded by latitudes
10°N and 50°N and longitudes 120°E and 160°E. The model employs dynamics linearised about a state of rest and incorporates
realistic bottom topography. It is driven by the seasonally varying part of the Hellerman and Rosenstein wind stress field
and by inflow along the northern and eastern boundaries specified from a 1°×1° version of the model applied to the whole North
Pacific. The model-calculated transport variations through the Tokara Strait are similar to those of the observed seasonal
sea level differences across the Strait, although the model appears to underestimate the amplitude of the signal by a factor
of at least 2. The inclusion of realistic bottom topography is shown to be crucial in determining the model response. 相似文献