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Evaluation of Nonbreaking Wave-Induced Mixing Parameterization Schemes Based on a One-Dimensional Ocean Model

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Journal of Ocean University of China 2024年第3期23卷 567-576页

作者： TANG Ran HUANG Chuanjiang dai dejun WANG Gang The First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

Surface waves have a considerable effect on vertical mixing in the upper *** the past two decades,the vertical mixing induced through nonbreaking surface waves has been used in ocean and climate models to improve the simulation of the upper *** far,several nonbreaking wave-induced mixing parameterization schemes have been proposed;however,no quantitative comparison has been performed among *** this paper,a one-dimensional ocean model was used to compare the performances of five schemes,including those of Qiao et al.(Q),Hu and Wang(HW),Huang and Qiao(HQ),Pleskachevsky et al.(P),and Ghantous and Babanin(GB).Similar to previous studies,all of these schemes can decrease the simulated sea surface temperature(SST),increase the subsurface temperature,and deepen the mixed layer,thereby alleviating the common thermal deviation problem of the ocean model for upper ocean *** these schemes,the HQ scheme exhibited the weakest wave-induced mixing effect,and the HW scheme exhibited the strongest effect;the other three schemes exhibited roughly the same *** particular,the Q and P schemes exhibited nearly the same *** the simulation based on observations from the Ocean Weather Station Papa,the HQ scheme exhibited the best performance,followed by the Q *** the experiment with the HQ scheme,the root-mean-square deviation of the simulated SST from the observations was 0.43℃,and the mixed layer depth(MLD)was 2.0 *** a contrast,the deviations of the SST and MLD reached 1.25℃ and 8.4 m,respectively,in the experiment without wave-induced mixing.

关键词： wave-induced mixing surface waves sea surface temperature mixed layer depth General Ocean Turbulence Model

Estimation of vertical diffusion coefficient based on a onedimensional temperature diffusion equation with an inverse method

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Acta Oceanologica Sinica 2014年第5期33卷 28-36页

作者： LIANG Hui ZHAO Wei dai dejun ZHANG Jun Physical Oceanography Laboratory Ocean University of China The First Institute of Oceanography State Oceanic Administration Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration The Third Institute of Oceanography State Oceanic Administration

Diapycnal mixing is important in oceanic circulation. An inverse method in which a semi-explicit scheme is applied to discretize the one-dimensional temperature diffusion equation is established to estimate the vertical temperature diffusion coefficient based on the observed temperature profiles. The sensitivity of the inverse model in the idealized and actual conditions is tested in detail. It can be found that this inverse model has high feasibility under multiple situations ensuring the stability of the inverse model, and can be considered as an efficient way to estimate the temperature diffusion coefficient in the weak current regions of the ocean. Here, the hydrographic profiles from Argo floats are used to estimate the temporal and spatial distribution of the vertical mixing in the north central Pacific based on this inverse method. It is further found that the vertical mixing in the upper ocean displays a distinct seasonal variation with the amplitude decreasing with depth, and the vertical mixing over rough topography is stronger than that over smooth topography It is suggested that the high-resolution profiles from Argo floats and a more reasonable design of the inverse scheme will serve to understand mixing processes.

关键词： inverse method temperature diffusivity one-dimensional vertical diffusion equation

Drift characteristics of green macroalgae in the Yellow Sea in 2008 and 2010

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Chinese Science Bulletin 2011年第21期56卷 2236-2242页

作者： QIAO FangLi WANG GuanSuo LüXinGang dai dejun The First Institute of Oceanography State Oceanic AdministrationQingdao 266061China Key Laboratory of Marine Science and Numerical Modeling(MASNUM) State Oceanic AdministrationQingdao 266061China

In order to investigate the aggregation mechanism of green macroalgae (Enteromorpha prolifera) on the Qingdao coastline,the macroalgal drift characteristics in the Yellow Sea during June and July in 2008 and 2010 were simulated using a three-dimensional wave-tide-circulation coupled *** June 2008,the monthly-mean surface current flowed onshore and its direction was almost perpendicular to the Qingdao coastline,which was identified as the main reason for a huge accumulation of algae in the coastal waters off *** current became parallel to the coastline in July 2008;this shift in current direction led to little accumulation of algae near Qingdao and thus relieved the environmental pressure on the Olympic sailing *** using the coupled model,we predicted that there would be no serious algal accumulation at Qingdao in late June 2010,which was later confirmed by *** study demonstrated that the drift path of macroalgae near Qingdao is mainly controlled by the surface current,which is primarily driven by *** climate change is therefore one of the means by which physical processes affect marine ecosystems.

关键词：海藻黄海海洋生态系统区域气候变化耦合模型海岸线聚集机制模型模拟

Three dimensional simulation of internal wave attractors in the Luzon Strait

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Acta Oceanologica Sinica 2015年第11期34卷 14-21页

作者： WANG Gang ZHENG Quanan LIN Min dai dejun QIAO Fangli Key Laboratory of Marine Science and Numerical Modeling (MASNUM) the First Institute of Oceanography State Oceanic Administration Key Laboratory of Data Analysis and Applications the First Institute of Oceanography State Oceanic Administration Department of Atmospheric and Oceanic Science University of Maryland College Park Department of Mathematics Ocean University of China

Internal waves propagate along wave beams that are inclined with respect to the horizontal plane. It is conjectured that the internal waves generated in the Luzon Strait may be confined between the double ridges in the strait and concentrate to a closed trajectory, the so-called internal wave attractor, due to the reflection of wave beams from the lateral boundaries, sea surface and bottom. This work carried out two experiments using a three dimensional non-hydrostatic general circulation model, MITgcm, to investigate the possibility that the ridges in the Lnzon Strait allows for internal wave attractors. Baroclinic current in both of the experiments demonstrate the forming of ring-like patterns in some section around 20° and 21°N, indicating that the development of the internal wave attractors are allowed in the Luzon Strait. The different resolutions and initial conditions in the two experiments also reveal that the internal-wave-attractor phenomenon is robust in this region.

关键词： Internal wave attractor non-hydrostatic wave beam Luzon Strait

A 2D-numerical modeling of the generation and propagation of internal solitary waves in the Luzon Strait

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Acta Oceanologica Sinica 2010年第6期29卷 1-11页

作者： WANG Gang QIAO Fangli dai dejun Key laboratory of Marine Science and Numerical Modeling （MASNUM） First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

The wide presence of internal solitary waves （ISWs） in the northern South China Sea （SCS） has been confirmed by both Synthetic Aperture Radar （SAR） images and in situ *** ISWs are believed being generated over the varying topography in the Luzon *** typically propagate westwards into the SCS with a diurnal or semidiurnal *** generation sites are,however,not yet solidly *** obtain a clear picture of the ISWs,we designed numerical experiments to analyze the generation and propagation of the ISWs in the Luzon Strait using a 2-dimensional non-hydrostatic *** model current is forced by barotropic or baroclinic currents imposed at open *** experiments show that the tidal current serves as a kind of triggering force for the ISWs over the submarine ridges in the *** the forcing of tidal currents,depressions are formed near the *** ISWs then split from the depressions through a process different from lee-wave generation *** appearance of the ISWs is influenced by the strength and period of the forcing current： the ISWs are more likely to be generated by a stronger tidal *** is why the ISWs in the Luzon Strait are frequently observed during spring *** with diurnal tidal current,the ISWs generated by semidiurnal tidal current with the same amplitude is much more *** is partly because that the wave beams in diurnal frequency have a larger angle with the vertical direction,thus are more likely to be reflected by the topography *** impact of the Kuroshio to the ISWs is also analyzed by adding a vertical uniform or shear current at boundaries.A vertically uniform current may generate ISWs *** the other hand,a vertically shear current,which is more realistic to represent the Kuroshio branch,seems to have little influence on the generation process and radiating direction of the ISWs in the Luzon Strait.

关键词： internal solitary waves Luzon Strait Synthetic Aperture Radar

The Equilibrium Range of Wind Wave Spectra: an Explanation Based on White Noise

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Journal of Ocean University of China 2007年第4期6卷 345-348页

作者： dai dejun WANG Wei QIAO Fangli YUAN Yeli Key Laboratory of Marine Science and Numerical Modeling SOA Qingdao 266061 P. R. China The First Institute of Oceanography SOA Qingdao 266061 P. R. China Physical Oceanography Laboratory Ocean University of China Qingdao 266003 P R. China

Laboratory experiments and field observations show that the equilibrium range of wind wave spectra presents a – 4 power law when it is scaled properly. This feature has been attributed to energy balance in spectral space by many researchers. In this paper we point out that white noise on an oscillation system can also lead to a similar inverse power law in the corresponding displacement spectrum, implying that the – 4 power law for the equilibrium range of wind wave spectra may probably only reflect the randomicity of the wind waves rather than any other dynamical processes in physical space. This explanation may shed light on the mechanism of other physical processes with spectra also showing an inverse power law, such as isotropic turbulence, internal waves, etc.

关键词： wind wave spectrum equilibrium range -4 power law white noise

Predicting the spread of nuclear radiation from the damaged Fukushima Nuclear Power Plant

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Chinese Science Bulletin 2011年第18期56卷 1890-1896页

作者： QIAO FangLi WANG GuanSuo ZHAO Wei ZHAO JieChen dai dejun SONG YaJuan SONG ZhenYa First Institute of Oceanography State Oceanic Administration Qingdao 266061 China

Japan suffered a M9.0 earthquake and massive tsunami on March 11, 2011, which seriously damaged the Fukushima Nuclear Power Plant and caused a nuclear crisis. The spread of nuclear radiation from the power plant through the atmosphere and ocean was predicted with a short-term climate forecasting model and an ocean circulation model under some idealized assumptions. If nuclear matter were leaked in the near-ground layer of 992 hPa, the climate model results show that the nuclear radiation would cover North America 10 days after the initial leakage, with the concentration at the forefront dramatically reduced to 10 millionths of the initial model concentration at the source. The radiation would span Europe in 15 days and cover much of the Northern Hemisphere in 30 days. If the initial leakage was assumed to occur in the layer 5000-m above the ground, the radiation would cover Europe in 10 days and cover much of the Northern Hemisphere in 15 days. Moreover, under the assumption that the nuclear matter leaked in the 10000-m layer, the radiation would affect much of China after 10 days. The ocean circulation model indicates that the nuclear material would be slowly transported northeast of Fukushima and reach 150°E in 50 days, and the nuclear debris in the ocean would be confined to a narrow band. Compared with the spread in the ocean, the area affected by leaked nuclear radiation in the atmosphere would be very large. Atmospheric monitors in North America and Europe will be helpful for estimating the effect in China of any leaked nuclear material.

关键词：扩散预测核辐射核电厂短期气候预测模型损坏大气监测环流模型近地面层

Using Combinational Logic Function to Watermark IP Based on FPGA

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1679-1682页

作者： MIAO Sheng dai Guanzhong MU dejun LI Meifeng College of Automation Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

In the field of digital circuit design, the extensive applications of reusable intellectual property （IP） simplify the design procedure based on very large scale field programmable gate array （FPGA）, and shorten the time to market （TTM）. However, the flexibility of reusable IP makes itself easy to be stolen and illegally distributed by intruders. The protection method proposed in this paper maps IP owner＇s signature to combinational logic functions, and then implements these functions into unused lookup tables （LUTs） in the design based on FPGA, which can be used as a strong proof of IPs ownership. The related experiment results show that this protection method has favorable characteristics such as low overhead, few effects on performance, and high security.

关键词： field programmable gate array watermark intellectual property

A possible generation mechanism of the strong current over the northwestern shelf of the South China Sea

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Acta Oceanologica Sinica 2011年第3期30卷 27-32页

作者： WANG Gang QIAO Fangli dai dejun HOU Yijun Key laboratory of Data Analysis and Applications （LDAA） Key laboratory of Marine Science and Numerical Modeling （MASNUM） First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Continuous observation in late April 2005 on the northwestern shelf of the South China Sea reveals vigorous strong currents, the maximum velocity of which exceeds 3.8 m/s. The strong currents occurred around spring tide period, when the internal tide waves were also expected to be vigorous. Analysis shows that the major peaks of the current power spectrum are in low frequency band. Using a numerical method applied to the actual ocean stratification, we find that the amplitude profiles of the strong current are similar to that of the currents induced by some low-mode internal waves （at diurnal or semi-diurnal frequency）. It indicates that the temporal and spatial features of strong currents were possibly induced by low frequency internal waves.

关键词： strong current internal waves Brunt-Vaisala frequency