1998 Vol. 20, No. 3
Display Method:
1998, 20(3): 1-5.
Abstract:
This study is concerned with the physical interpretations for the statistical uncertainty of the spectral peak energy and peak frequency of the Fourier freyuency spectrum.The local wavelet energy spectrum,based on the wavelet transform,is introduced to analyze the wind wave data obtained in a wind wave channel.It is shown that wave energy exhibits localizations both in scale (frequency) and physical space (time),which implies energy intermittency——the energy at a given frequency may not be evenly distributed in the whole time.Especially,the peak energy and the corresponding peak frequency of a local wavelet energy spectrum have significant fluctuations as time evolves.Such intermittency and fluctuations give appropriate interpretations for the above mentioned statistical uncertainty.
This study is concerned with the physical interpretations for the statistical uncertainty of the spectral peak energy and peak frequency of the Fourier freyuency spectrum.The local wavelet energy spectrum,based on the wavelet transform,is introduced to analyze the wind wave data obtained in a wind wave channel.It is shown that wave energy exhibits localizations both in scale (frequency) and physical space (time),which implies energy intermittency——the energy at a given frequency may not be evenly distributed in the whole time.Especially,the peak energy and the corresponding peak frequency of a local wavelet energy spectrum have significant fluctuations as time evolves.Such intermittency and fluctuations give appropriate interpretations for the above mentioned statistical uncertainty.
1998, 20(3): 6-11.
Abstract:
1998, 20(3): 12-18.
Abstract:
In this paper,the spatial evolution of the third-order moment (i.e.,the skewness) of the sea surface elevation for nonbreaking shoaling random waves versus Hs/d is analyzed by using the data obtained in field and laboratory.Using the empirical relationship given in this paper,the nonlinear model for the sea surface elevation of nonbreaking shoaling waves in the second-order approximation by expanding the first two terms of Hermitian polynomial is depicted by the parameter Hs/d,and such characteristics as the power spectrum,the bispectrum and the distribution function of sea surface elevation as well have been derived in this paper.The correlation between the skewness and the kurtosis of the sea surface elevation is also discussed.
In this paper,the spatial evolution of the third-order moment (i.e.,the skewness) of the sea surface elevation for nonbreaking shoaling random waves versus Hs/d is analyzed by using the data obtained in field and laboratory.Using the empirical relationship given in this paper,the nonlinear model for the sea surface elevation of nonbreaking shoaling waves in the second-order approximation by expanding the first two terms of Hermitian polynomial is depicted by the parameter Hs/d,and such characteristics as the power spectrum,the bispectrum and the distribution function of sea surface elevation as well have been derived in this paper.The correlation between the skewness and the kurtosis of the sea surface elevation is also discussed.
1998, 20(3): 19-26.
Abstract:
Based on the quantitative analyses of affecting factors in Offshore-SST Anomaly (U-SSTA) model,the most favorable atmospheric forcing systems for forming of warm/cold anomaly among U-SSTA are recognized.The different forming time scale and chief factors between the both are indicated.A sample of experiment forecast is chosen,its initial values are formed and the model is run.Finally,the results of experiment forecast are checked.
Based on the quantitative analyses of affecting factors in Offshore-SST Anomaly (U-SSTA) model,the most favorable atmospheric forcing systems for forming of warm/cold anomaly among U-SSTA are recognized.The different forming time scale and chief factors between the both are indicated.A sample of experiment forecast is chosen,its initial values are formed and the model is run.Finally,the results of experiment forecast are checked.
1998, 20(3): 27-35.
Abstract:
Based on the Ueosat altimetric data of an ascending orbit over the western Pacific on August 11,1987,the features of sea surface wind and wave under the influence of typhoon Betty are analyzed.It is shown that the spatial distributions of wind speed and wave height are asymmetric to the center of the typhoon.In the direction of the typhoon movement,the wind speed in the right quadrant increased more rapidly than that in the left within the inner area of the typhoon,while in the outer area the former also decreased more rapidly than the latter.However,unlike the wind speed,the spatial distribution of wave height has no obvious division between inner and outer areas.The wave height in the left and right quadrant shows the different distributions with the distance increasing to the typhoon center.The relationships between wind speed and wave height in the right and the left quadrant are obviously different.The empirical formulas are established on the variations in wind speed and wave height with the distance to the typhoon center and on the relationship between wind speed and wave heieht.
Based on the Ueosat altimetric data of an ascending orbit over the western Pacific on August 11,1987,the features of sea surface wind and wave under the influence of typhoon Betty are analyzed.It is shown that the spatial distributions of wind speed and wave height are asymmetric to the center of the typhoon.In the direction of the typhoon movement,the wind speed in the right quadrant increased more rapidly than that in the left within the inner area of the typhoon,while in the outer area the former also decreased more rapidly than the latter.However,unlike the wind speed,the spatial distribution of wave height has no obvious division between inner and outer areas.The wave height in the left and right quadrant shows the different distributions with the distance increasing to the typhoon center.The relationships between wind speed and wave height in the right and the left quadrant are obviously different.The empirical formulas are established on the variations in wind speed and wave height with the distance to the typhoon center and on the relationship between wind speed and wave heieht.
1998, 20(3): 36-39.
Abstract:
Based on the Nansha Islands' closed atoll conception-remote sensing system in Part Ⅰ,through the solution of the information function value and isostatic value of closed and quasi-closed atoll,and by using topological analysis on growth form and the efficients,the feature vector system and its composite remote sensing yuantization data as the calculation comathematical model of two kinds of atoll are built,and the multivariate analysis is made with some examples.
Based on the Nansha Islands' closed atoll conception-remote sensing system in Part Ⅰ,through the solution of the information function value and isostatic value of closed and quasi-closed atoll,and by using topological analysis on growth form and the efficients,the feature vector system and its composite remote sensing yuantization data as the calculation comathematical model of two kinds of atoll are built,and the multivariate analysis is made with some examples.
1998, 20(3): 40-46.
Abstract:
SSM/I data on the Bohai Sea of China from 1994 to 1996 have been studied.The sea ice algorithms of calibration/validation such as the brightness temperature index [AES/YORK TBI (Hollinger et al.,1992)] and ocean scattering index [OSI (Ferraro et al.,1996,The Bulletin of the American Meteorological Society,77 C5),891-905)] are not applicable to the detection of regional sea ice of mid-latitude Bohai Sea area.A method of the scattering index SI and polarization index PI to identify regional Bohai Sea ice is prerented.Numerical results of vector radiative transfer for a model a layer of sea ice over ocean simulate the relationship between SI/PI and sea ice depth,and others.It is employed to categorize the SI/PI indices for the detection of sea ice.
SSM/I data on the Bohai Sea of China from 1994 to 1996 have been studied.The sea ice algorithms of calibration/validation such as the brightness temperature index [AES/YORK TBI (Hollinger et al.,1992)] and ocean scattering index [OSI (Ferraro et al.,1996,The Bulletin of the American Meteorological Society,77 C5),891-905)] are not applicable to the detection of regional sea ice of mid-latitude Bohai Sea area.A method of the scattering index SI and polarization index PI to identify regional Bohai Sea ice is prerented.Numerical results of vector radiative transfer for a model a layer of sea ice over ocean simulate the relationship between SI/PI and sea ice depth,and others.It is employed to categorize the SI/PI indices for the detection of sea ice.
1998, 20(3): 47-55.
Abstract:
The contents of 10 major chemical compositions of 33 samples in the surface sediments of Haitan Island seas are determined,the horizontal distributions of these composition are described and their control factors are discussed.Correlation analysis shows that positive correlation between pairs of elements,i.e.Corg,N,P,Fe,Al,Ti and Mg,is significant,and with clay they all correlate closely and are derived from terrigenous input.As to calcium and carbonate there is a high positive correlation between themselves,but there are negative correlations between them and clay as well as above elements,respectively.And they are enriched in biogenic shells in coarse sediments.Concerning Mn,it exists mainly as detritus and is also considered as authigenic deposit in gravel sand.By the aid of hierarchical clustering method of Q model,as it stands,the sediments may be classified into three geochemical sedimentary zones,which do reflect their geochemical characteristics comprehensively.
The contents of 10 major chemical compositions of 33 samples in the surface sediments of Haitan Island seas are determined,the horizontal distributions of these composition are described and their control factors are discussed.Correlation analysis shows that positive correlation between pairs of elements,i.e.Corg,N,P,Fe,Al,Ti and Mg,is significant,and with clay they all correlate closely and are derived from terrigenous input.As to calcium and carbonate there is a high positive correlation between themselves,but there are negative correlations between them and clay as well as above elements,respectively.And they are enriched in biogenic shells in coarse sediments.Concerning Mn,it exists mainly as detritus and is also considered as authigenic deposit in gravel sand.By the aid of hierarchical clustering method of Q model,as it stands,the sediments may be classified into three geochemical sedimentary zones,which do reflect their geochemical characteristics comprehensively.
1998, 20(3): 56-63.
Abstract:
In order to study the relationship between 1 nm manganate and 0.7 nm manganate,a series of S1nm M2+ manganates are made after the synthetic lnm manganate (S1nm Na+) substituted with the different kinds of divalent canons.The X-ray deffraction analysis of S1nm M2+ manganates when they are wet and after 24 h room temperature dry shows their quite different characteristics of the d-spacing and indicates that there are phase changes between 1 nm manganate and 0.7 nm manganate.Those lnm manganates with unstable layer structure will collapse to 0.7 nm manganate by tossing one inter layer OH-H20 after RTD,while those with stable layer structure will still remain their lnm d-spacing.This fact reminds us that the samples of manganese nodules must be kept in wet when we do the mineral analysis to avoid the uncorrect results.The structural stability of lnm manganate is mainly controlled by the interlayer divalent cations such as Cu,Co and Ni.There is positive relationship between the interlayer contents of the divalent cations and their structural stability,while the capacity of different cations in stabilizing the layer structure of lnm manganate is as follows:Ni>Cu>Co>Zn>Ca>Mg>Na.
In order to study the relationship between 1 nm manganate and 0.7 nm manganate,a series of S1nm M2+ manganates are made after the synthetic lnm manganate (S1nm Na+) substituted with the different kinds of divalent canons.The X-ray deffraction analysis of S1nm M2+ manganates when they are wet and after 24 h room temperature dry shows their quite different characteristics of the d-spacing and indicates that there are phase changes between 1 nm manganate and 0.7 nm manganate.Those lnm manganates with unstable layer structure will collapse to 0.7 nm manganate by tossing one inter layer OH-H20 after RTD,while those with stable layer structure will still remain their lnm d-spacing.This fact reminds us that the samples of manganese nodules must be kept in wet when we do the mineral analysis to avoid the uncorrect results.The structural stability of lnm manganate is mainly controlled by the interlayer divalent cations such as Cu,Co and Ni.There is positive relationship between the interlayer contents of the divalent cations and their structural stability,while the capacity of different cations in stabilizing the layer structure of lnm manganate is as follows:Ni>Cu>Co>Zn>Ca>Mg>Na.
1998, 20(3): 64-75.
Abstract:
In this paper,the horizontal distributions and seasonal variabilities of the chlorophyll a maximum in the northern East China Sea are studied using the observation data during the SinoJapan Joint investigation and study on the Kuroshio (1986-1992).It is shown from the study that the hydrodynamic conditions in the northern East China Sea,such as frontal eddy,oceanic front and upwelling are important environmental factorsto result in the chlorophyll a maximum distributions and variations.It is especially pointed out that the distance from the high chlorophyll a value area to the frontal surface shows a negative correlsation with the current speed gradient in the frontal area,and the location of the high chlorophyll a value area can be estimated by using the correlation.
In this paper,the horizontal distributions and seasonal variabilities of the chlorophyll a maximum in the northern East China Sea are studied using the observation data during the SinoJapan Joint investigation and study on the Kuroshio (1986-1992).It is shown from the study that the hydrodynamic conditions in the northern East China Sea,such as frontal eddy,oceanic front and upwelling are important environmental factorsto result in the chlorophyll a maximum distributions and variations.It is especially pointed out that the distance from the high chlorophyll a value area to the frontal surface shows a negative correlsation with the current speed gradient in the frontal area,and the location of the high chlorophyll a value area can be estimated by using the correlation.
1998, 20(3): 76-81.
Abstract:
It is shown that the general trend of sea level change has been subsided in recent 43 a in Qinhuangdao,its rate of change is -2.1~-2.4mm/a.After correcting the sea level change rate caused by the earth crust rise,subsidence rate is -1.3~-1.6mm/a,and based on coast sectioning relative annual change rate is known.
It is shown that the general trend of sea level change has been subsided in recent 43 a in Qinhuangdao,its rate of change is -2.1~-2.4mm/a.After correcting the sea level change rate caused by the earth crust rise,subsidence rate is -1.3~-1.6mm/a,and based on coast sectioning relative annual change rate is known.
1998, 20(3): 82-90.
Abstract:
There is a huge tidal sand system which is composed of the old sand body distributing in the coastal plain and the radial sand ridge distributing in south Huanghai Sea.Based on numerous drilling and geological ladar prospecting data,this paper emphatically studied the hydrodynamic environment and source of the old sand body by mains of magnetic fabric and heavy mineral analyses on the representative drilling cores.The results show that the old sand body was produced by tidal current in a hydrodynamic environment similar to the convergent-divergent tidal current field in south Huanghai Sea.The silt,which mainly came from the Changjiang River in the early and from the Huanghai River as well as the Changjiang River in the latter stage,was transported into the tidal current field by longshore current.So,the old sand body is a result of the middle-late Holocene continental-oceanic interaction.
There is a huge tidal sand system which is composed of the old sand body distributing in the coastal plain and the radial sand ridge distributing in south Huanghai Sea.Based on numerous drilling and geological ladar prospecting data,this paper emphatically studied the hydrodynamic environment and source of the old sand body by mains of magnetic fabric and heavy mineral analyses on the representative drilling cores.The results show that the old sand body was produced by tidal current in a hydrodynamic environment similar to the convergent-divergent tidal current field in south Huanghai Sea.The silt,which mainly came from the Changjiang River in the early and from the Huanghai River as well as the Changjiang River in the latter stage,was transported into the tidal current field by longshore current.So,the old sand body is a result of the middle-late Holocene continental-oceanic interaction.
1998, 20(3): 91-97.
Abstract:
Based on data of demersal trawl samples from 1987 to 1988 in the Zhujiang estuary and adjacent waters relationships between fish community and environmental factors were studied by using classification,MDS ordination and several community parameters.The results showed that the distribution of fish species was zoned with salinity and divided into three types.The fresh water community which was restricted in the Lianhua Mountain-Humen waterway was simple and stable,the coastal community which lived in the shallow waters was complex,and the estuary community which was identified in the Lingdingyang areas and affected by physical and ecological process more greatly had obvious seasonal variations.
Based on data of demersal trawl samples from 1987 to 1988 in the Zhujiang estuary and adjacent waters relationships between fish community and environmental factors were studied by using classification,MDS ordination and several community parameters.The results showed that the distribution of fish species was zoned with salinity and divided into three types.The fresh water community which was restricted in the Lianhua Mountain-Humen waterway was simple and stable,the coastal community which lived in the shallow waters was complex,and the estuary community which was identified in the Lingdingyang areas and affected by physical and ecological process more greatly had obvious seasonal variations.
1998, 20(3): 98-103.
Abstract:
Based on Taking the Ostracod in near seas of China as an object of study,this paper divided the community of Ostracod into the inshore,the edge area of Continental Shelf,the offcoast and the transitional community which is nonstable and sometime isolate,and also main characteristic of every community and structure of special species in it was described,in addition,this paper discusses just the community structure of Ostracod inside the water from 0 to 200m depth.
Based on Taking the Ostracod in near seas of China as an object of study,this paper divided the community of Ostracod into the inshore,the edge area of Continental Shelf,the offcoast and the transitional community which is nonstable and sometime isolate,and also main characteristic of every community and structure of special species in it was described,in addition,this paper discusses just the community structure of Ostracod inside the water from 0 to 200m depth.
1998, 20(3): 104-109.
Abstract:
The body length and weight and ingestion rate of adult Centropages tenuiremis Thompson and Scott in Xiamen Harbor were studied.The results showed that the body length and weight have significant seasonal variations,they are bigger in winter and spring than that in earlier summer and later autumn.There is negative correlation between the body size and field sea water temperature.The seasonal variation in ingestion rate is relatively significant.Ingestion rate of adult female is larger than that of adult male.Water temperature effects notably on weight specific ingestion rate (♀:Ic'=0.056t-0.249,r=0.710;♂:Ic'=0.034t-0.315,r=0.798).
The body length and weight and ingestion rate of adult Centropages tenuiremis Thompson and Scott in Xiamen Harbor were studied.The results showed that the body length and weight have significant seasonal variations,they are bigger in winter and spring than that in earlier summer and later autumn.There is negative correlation between the body size and field sea water temperature.The seasonal variation in ingestion rate is relatively significant.Ingestion rate of adult female is larger than that of adult male.Water temperature effects notably on weight specific ingestion rate (♀:Ic'=0.056t-0.249,r=0.710;♂:Ic'=0.034t-0.315,r=0.798).
1998, 20(3): 110-118.
Abstract:
The characteristic and mechanism of ice force stochastic process (IFSP) are discussed first.IFSP is classified into crushing failure process,bulking failure process and bending failure process according to the failure mode of ice.After spectrum analysis of 37 pieces of ice force vs.time sampling lines in crushing mode,which are selected from the field data of ice force surveyed at the Bohai Sea area,the corresponding spectrum density and its parameters are determined.Through further statistical analysis the relationship between spectrum parameters and ice thickness is established.Based on this results,the stochastic field model of ice force encircling upright column is obtained.The function of statistical field is given through statistical regressive analysis to large amount of field data.The stochastic process of total ice force on upright column and its spectrum density can be conveniently determined from the stochastic field model.
The characteristic and mechanism of ice force stochastic process (IFSP) are discussed first.IFSP is classified into crushing failure process,bulking failure process and bending failure process according to the failure mode of ice.After spectrum analysis of 37 pieces of ice force vs.time sampling lines in crushing mode,which are selected from the field data of ice force surveyed at the Bohai Sea area,the corresponding spectrum density and its parameters are determined.Through further statistical analysis the relationship between spectrum parameters and ice thickness is established.Based on this results,the stochastic field model of ice force encircling upright column is obtained.The function of statistical field is given through statistical regressive analysis to large amount of field data.The stochastic process of total ice force on upright column and its spectrum density can be conveniently determined from the stochastic field model.
1998, 20(3): 119-128.
Abstract:
A time domain analysis is presented for predicting vorex-shedding induced transverse vibration of tension leg platform (TLP) tethers which are subject to wave,current and oscillatory displacements at their upper end both in horizontal and vertical directions.Periodical variations of tether's tension caused by heaving oscillation of TLP play the role of a parametric exciter to vortex-induced vibration,and make it more complicared.In this paper,the conditions of structure-flow resonant caused by vortex,accounting for the effects of tension's parametric excitation are discussed;a method for analysis of TLP tether's dynamic responses to vortex and heaving oscillation is put forth.The time history of displacements,bending moments and shear forces of the tether are computed by the presented.It is shown clearly that the parametric excitation can raise the amplitudes of vortex-induced transverse vibration,increase the components of high frequent responses.The importance of tension variation for fatigue design of TLP tethers is illustrated.
A time domain analysis is presented for predicting vorex-shedding induced transverse vibration of tension leg platform (TLP) tethers which are subject to wave,current and oscillatory displacements at their upper end both in horizontal and vertical directions.Periodical variations of tether's tension caused by heaving oscillation of TLP play the role of a parametric exciter to vortex-induced vibration,and make it more complicared.In this paper,the conditions of structure-flow resonant caused by vortex,accounting for the effects of tension's parametric excitation are discussed;a method for analysis of TLP tether's dynamic responses to vortex and heaving oscillation is put forth.The time history of displacements,bending moments and shear forces of the tether are computed by the presented.It is shown clearly that the parametric excitation can raise the amplitudes of vortex-induced transverse vibration,increase the components of high frequent responses.The importance of tension variation for fatigue design of TLP tethers is illustrated.
1998, 20(3): 129-133.
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1998, 20(3): 134-139.
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1998, 20(3): 140-148.
Abstract:
Based on analysis of hydrodynamic conditions in the Nandu River Delta's north coast,this paper analysizes Nandu River Delta's river mouth process and its impact on adjacent coast's evolution,detailedly studies erosion or siltation of various coast segments,discusses the time-scales of coastal evolution and their relevant effecting factors and the trend of coastal evolution.
Based on analysis of hydrodynamic conditions in the Nandu River Delta's north coast,this paper analysizes Nandu River Delta's river mouth process and its impact on adjacent coast's evolution,detailedly studies erosion or siltation of various coast segments,discusses the time-scales of coastal evolution and their relevant effecting factors and the trend of coastal evolution.
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