检索结果-南通市图书馆

AN EXTENDED modeling OF TIDE-WAVE MOTION

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2001年第3期13卷 100-106页

作者： zhang qing hua, Xu Hao, Qu Yuan yuan First Institute of Oceanography,{2.,{3., china key laboratory of marine science and numerical modeling,{2.,{3., china First Inst. of Oceanography State Oceanic Administration Qingdao 266061 China

By vertical boundary conditions, a spectral expansion of horizontal tide wave velocity is done in vertical direction in terms of a complete basis functions selected properly, hence a relation between tide levels and spectral components is found theoretically under condition of ignoring the horizontal friction stress and nonlinear effect. And a relation between bottom friction of tide current, which satisfies the viscous condition on sea bottom, and tide levels is determined. The relation is different from the relation of the traditional parameterizing of bottom friction. Moreover integration of the continuity equation and momentum equations is carried out in the vertical direction using zero flux condition on solid boundaries and inputting condition on open boundaries, and then a boundary value problem of elliptic form on the tide levels is constructed.

关键词： tide waves basis function spectral expansion bottom friction

UNIFICATION AND APPliCATIONS OF MODERN oceanic/ATMOSPHERIC DATA ASSIMILATION ALGORITHMS

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2004年第5期16卷 501-517页

作者： QIAOFang-li zhangShao-qing YUANYe-li InstituteofOceanography ChineseAcademyofSciencesQingdao266071China GeophysicalFluidDynamicslaboratory PrincetonUniversityPrincetonNJ08542USA keylaboratoryof{2.{3.and{3.modeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

The key mathematics and applications of various modern atmospheric/oceanicdata assimilation methods including Optimal Interpolation (OI), 4-dimensional variational approach(4D-Var) and filters were systematically reviewed and classified. Based on the data assimilationphilosophy, i. e. , using model dynamics to extract the observational information, the commoncharacter of the problem, such as the probabilistic nature of the evolution of theatmospheric/oceanic system, noisy and irregularly spaced observations, and the advantages anddisadvantages of these data assimilation algorithms, were discussed. In the filtering framework, allmodern data assimilation algorithms were unified: OI/3.-Var is a stationary filter, 4D-Var is alinear (Kalman) filter and an ensemble of Kalman filters is able to construct a nonlinear *** nonlinear filter such as the Ensemble Kalman Filter (EN-KF), Ensemble Adjustment Kalman Filter(EAKF) and Ensemble Transformation Kalman Filter (ETKF) can, to some extent, account for thenon-Gaussian information of the prior distribution from the model. The flow-dependent covarianceestimated by an ensemble filter may be introduced to OI and 4D-Var to improve these traditionalalgorithms. In practice, the performance of algorithms may depend on the specific numerical modeland the choice of algorithm may depend on the specific problem. However, the unification ofalgorithms allows us to establish a unified test system to evaluate these algorithms, which providesmore insights into data assimilation philosophies and helps improve data assimilation techniques.

关键词： data assimilation oceanic/atmospheric system filtering optimalinterpolation (OI) 4-dimensional variational(4D-Var) approach

KUROSHIO INTRUSION INTO THE SOUTH china SEA

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2006年第6期18卷 702-713页

作者： zhang qing-hua FAN Hai-mei QU Yuan-yuan Institute of Physical Oceanography Ocean University of China Qingdao 266003 China key laboratory of {2. {3. and {3. modeling State Oceanic Administration Qingdao 266061China

In this article, the circulation of the South china Sea （SCS）, which is idealized as the rectangular basin with constant depth, is studied under Kuroshio boundary forces. Starting from the linearly quasi-geostrophic vorticity equation, the solution of the SCS circulation is given in the form of corrected Fourier series under proper boundary conditions. The results show that the intruded current flows westward and separates into the northward branch and the southward branch before arriving at the western boundary. The southward branch flows out of the SCS through the southwestern passage, at the same time, the induced cyclonic （anti-clockwise） ring almost occupies the middle and southern parts, and concomitant anti-cyclonic （clockwise） vortex appears between the cyclone and the western boundary. While the northward branch outflows through the northeastern passage, the anti-cyclonic （clockwise） ring is triggered at the northern part of the SCS. The above two vortexes are both intensified if the south-entering and the north-leaving current loop intrusion are superposed. The outer flow of the northern vortex flows westward, then northward, and then eastward, and it is very similar to the configuration of the SCS Warm Current （SCSWC） at the northern part of the SCS, thus, a kind of generating mechanism of the SCSWC is presented.

关键词： Kuroshio boundary forces South china Sea (SCS) SCS Warm Current (SCSWC)

ANALYTIC METHOD FOR INVERSING THE OPEN BOUNDARY CONDITIONS IN A SEMI-CLOSED SEA AREA—CASE I FOR INVERSING THE TIDAL LEVELS AT OPEN BOUNDARY

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2004年第5期16卷 590-595页

作者： zhangqing-hua YINXun-qiang MA{2. QUYuan-yuan keylaboratoryof{2.{3.and{3.modeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China keylaboratoryof{2.{3.and{3.modeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

In this paper, a computational case was employed to describe thecomputational procedure for inversing the tidal level open boundary conditions using an analyticmethod. The area for finding the solution is a circular area with a circular arc with the openingangle 60°-being the open boundary and the other circular arc being the solid wall *** from the reestablished elliptic partial differential equation satisfied by the tidallevel function, the extended spectrum method was used to derive the general solution of the equationfor the sea of constant depth, and the impermeable solid wall condition (the second class boundarycondition) and the adequately specified open boundary conditions were then applied to determine theundetermined coefficients of the general solution, thus obtaining the tidal level distributionfunction. In this way, both the first and second class boundary values at the solid wall boundarywere obtained. With the above boundary values as the boundary conditions, the tidal level values atthe open boundary were then inversed by means of the general solution of tidal wave equation. Thevalidity of inversion method could be verified by comparing the inversed tidal level distributionswith the originally specified open boundary values.

关键词： semi-closed sea open boundary condition extended spectrum method generalsolution of equation in-version

AN ACCURATE SOLUTION OF THE liNEAR THEORY OF THE WIND-DRIVEN OCEAN CIRCULATION-I. THE GENERAliZED SOLUTION

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2003年第6期15卷 96-105页

作者： zhang qing-hua, Qu Yuan-yuan, Xia Chang-shui{2. {3. of {3. science and numerical modeling, state oceanic administration, First Institute of Oceanography, qingdao 266061, china, e-mail: qu-helen @ *** key laboratory of {2. {3. and {3. modeling State Oceanic Administration First Institute of Oceanography Qingdao 266061 China

To model the wind-driven ocean circulation of the isobath rectangular basin,the linear vorticity equation with the meridional friction terra was used compared to the Munk'stheory on the ocean circulation. The generalized solution of the vorlicity equation was thus wor{3.dout in the sense of Fourier averaging by using the corrected Fourier expansion. The method to obtainthe undetermined coefficients was presented using the viscous boundary conditions.

关键词： wind-driven ocean circulation meridional friction corrected fourierexpansion

Wave-current interaction during Typhoon Nuri(2.08)and Hagupit(2.08):an application of the coupled ocean-wave {3. system in the northern South china Sea

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and limnology 2018年第3期36卷 663-675页

作者： zhang Chen HOU Yijun li jian Institute of Oceanology Chinese Academy of SciencesQingdao 266071China key laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071 China University of Chinese Academy of sciences Beijing 100049China North china Sea Branch of state oceanic administration Qingdao 266071China qingdao National laboratory for {2. {3. and Technology Qingdao 266237China

The northern South china Sea(SCS) is frequently affected by typhoons. During severe storm events, wave-current interactions produce storm surges causing enormous damage in the path of the typhoon. To evaluate the influence of wave-current interactions on storm surge, we used a coupled ocean-atmospherewave-sediment transport(COAWST) modeling system with radiation-stress and vortex-force formulations to simulate two typically intense tropical storms that invaded the SCS, namely Typhoons Nuri(2.08) and Hagupit(2.08), and compared results with observations from the Hong Kong Observatory. Both radiationstress and vortex-force formulations significantly improved the accuracy of the simulation. Depending on which typhoon and the topography encountered, the influence of surface waves on the {2. circulation showed different characteristics, including the differences of range and intensity of storm surge between vortex-force and radiation-stress experiments. During typhoon landing, strong sea-surface elevation in concert with wave set-up/set-down caused the adjustment of the momentum balance. In the direction perpendicular to the current, but especially in the cross-shore direction, the pressure gradient and wave effects on the current dominated the momentum balance.

关键词： northern South china Sea wave-current interactions storm surge coupled ocean-atmosphere-wave-sediment transport(COAWST) modeling system

Habitat suitability of Scapharca subcrenata (lischke) inthe shallow water of the Xiaoheishan Island

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2016年第12期35卷 51-57页

作者： ZHOU jian SONG Jingjing BM Qianling liU Chengyue {3. Zhipeng TANG Haitian Shandong marine Forecast and Hazard Mitigation Service Qingdao 266104 China marine Biology Institute of Shandong Province Qingdao 266104 China Tianjin University of science and Technology Tianjin 300457 China College of marine life Ocean University of China Qingdao 266100 China Yantai marine Environment Monitoring Central Station of state oceanic administration Yantai 264006 China

The habitat suitability index(HSI) model was used to identify potential sites for sustainable restoration of ark shell, Scapharca subcrenata(lischke), in the shallow water of Xiaoheishan Island, using a geographic information system framework. The seven input variables of the HSI model were sediment composition, water temperature, salinity, dissolved oxygen, water depth, p H, and ammonia. A non-linear suitability function for each variable factor was used to transform the value into a normalized quality index ranging from 0(nonsuitability) to 1(best suitability). In present study, the analysis of habitat suitability was conducted for four seasons respectively. The majority of the study area has a high HSI value(>0.6) year round, which implies a strong suitability for restoration, with the optimal habitat located on the eastern side of the *** analysis indicated that water temperature was the main factor causing seasonal variation,while sediment composition and water depth were the two major reasons for the differences in sites. The results of this work could provide support for restoration decision making through identification of potential sites for sustainable establishment of S. subcrenata.

关键词： Scapharca subcrenata(lischke) habitat suitability index restoration shallow water

Unprecedent green macroalgae bloom:mechanism and implication to disaster prediction and prevention

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2023年第1期16卷 3772-3793页

作者： Mengmeng Cao Xuyan li Tingwei Cui Xinliang Pan Yan li Yanlong Chen Ning Wang Yanfang Xiao Xingai Song Yuzhu Xu Runa A Bing Mu Song {3. Rongjie liu Wenjing Zhao Yuhai Bao Jie zhang Lan Wei College of Geographical science Inner Mongolia Normal UniversityHohhotPeople’s Republic of China School of Atmospheric sciences Sun Yat-Sen University&Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of Education&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiPeople’s Republic of China Ministry of Natural Resources First Institute of OceanographyQingdaoPeople’s Republic of China National marine Environmental Monitoring Center DalianPeople’s Republic of China North china Sea marine Forecasting Center of{2. QingdaoPeople’s Republic of China Ministry of Natural Resources National Satellite Ocean Application ServiceBeijingPeople’s Republic of China Ocean University of china QingdaoPeople’s Republic of China Ministry of Ecology and Environment South China Institute of Environmental ScienceGuangzhouPeople’s Republic of China

Green macroalgae bloom(GMB),with the dominant species of Ulva prolifera,has regularly occurred since 2.07 along the china *** disaster prevention and control achieved favorable results in 2.2.,the satellite-observed GMB annual maximum coverage(AMC)rebounded sharply in 2.2. to an unprecedented *** reasons for this rebound and the significant interannual variability over past 15 years are still open ***,by using long-term time-series(2.07-2.2.)optical and Synthetic Aperture Radar satellite observations(1000+scenes),meteorological data and water quality statistics,the mechanism analysis was performed by exploring effects from natural factors and human *** key determinants for AMC are successfully identified from numerous potential factors which are the macroalgae distribution in a key area(the Subei Shoal)during a critical period(from April to May 2.)and the nutrient ***,by using these two parameters,a novel model for AMC prediction(R^(2.=0.87,plidated,which can reasonably explain the significant interannual variability(2.14-2.2.)and agree well with the latest observation in 2.2.(percentage difference 12.).Finally,suggestions are proposed for future disaster prevention and *** work may aid future bloom prediction and management measure optimization.

关键词： green macroalgae annual maximum coverage(AMC) the Yellow Sea Porphyra mariculture extreme weather water quality

Evaluation of Wind Retrieval from Co-Polarization Gaofen-3.SAR Imagery Around china Seas

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of china 2019年第1期18卷 80-92页

作者： SHAO Weizeng ZHU Shuai SUN jian YUAN Xinzhe SHENG Yexin zhang {2.jun JI Qiyan marine science and Technology College Zhejiang Ocean University Physical Oceanography laboratory/CIMST Ocean University of China and Qingdao National Laboratory for Marine Science and Technology National Satellite Ocean Application Service State Oceanic Administration Beijing Institute of Spacecraft System Engineering

Gaofen-3.GF-3. is the first Chinese space-borne satellite to carry the C-band multi-polarization synthetic aperture radar(SAR). marine applications, i.e., winds and waves retrieved from GF-3.SAR images, have been operational since January {3.17. In this study, we have collected more than 1000 quad-polarization(vertical-vertical(VV); horizontal-horizontal(HH); vertical-horizontal(VH); horizontal-vertical(HV)) GF-3.SAR images, which were acquired around the china Seas from September {3.16 to September {3.17. Wind streaks were visible in these images in co-polarization(VV and HH) channel. Geophysical model functions(GMFs), including the CMOD5N together with polarization ratio(PR) model and C-SARMOD, were used to retrieve winds from the collected co-polarization GF-3.SAR images. Wind directions were directly obtained from GF-3.SAR images. Then, the SAR-derived wind speeds were compared with the measurements at a 0.{3.? grid from the Advanced Scatterometer on board the Metop-A/B and microwave radiometer WindSAT. Based on the analysis, empirical corrections are proposed to improve the performance of the two GMFs. Results of this study show that the standard deviation of wind speed is 1.63.m s^(-1) with a 0.19 m s^(-1) bias and 1.71 m s^(-1) with a 0.{3. m s^(-1) bias for VV-and HH-polarization GF-3.SAR, respectively. Our work not only systematically evaluates wind retrieval by using the two advanced GMFs and PR models but also proposes empirical corrections to improve the accuracy of wind retrievals from GF-3.SAR images around the china Seas and thus enhance the accuracy of near real-time operational SAR-derived wind products.

关键词： Gaofen-3 synthetic aperture radar wind china Seas