1990 Vol. 9, No. 3
Display Method:
1990, (3): 315-329.
Abstract:
It is suggested that the shallow sea circulation should be related to the Lagrangian residual circulation but not to the conventional Eulerjan mean circulation, and further, the first order Lagrangian residual circulation the mass-transport velocity field is used to define the steady circulation as the lowest order shallow sea circulation.
The set of equation governing the shallow sea circulation is reformulated, which shows that there are no the so-called "tidal surface source" and the "tidal stress".A vorticity equation for the stream function of horizontal transports is derived, which is easily solved by the conventional numerical methods.
An intertidal convection-diffusion equation governing the concentration of conservative and passive tracer is derived.Differing from the conventional equation, the equation derived in the present paper reveals the Lagrangian convection and has no need to introduce the artificial hypothesis for the so-called "tidal dispersion".
The theory presented here is base on a three-dimensional weakly nonlinear dynamic system.
It is suggested that the shallow sea circulation should be related to the Lagrangian residual circulation but not to the conventional Eulerjan mean circulation, and further, the first order Lagrangian residual circulation the mass-transport velocity field is used to define the steady circulation as the lowest order shallow sea circulation.
The set of equation governing the shallow sea circulation is reformulated, which shows that there are no the so-called "tidal surface source" and the "tidal stress".A vorticity equation for the stream function of horizontal transports is derived, which is easily solved by the conventional numerical methods.
An intertidal convection-diffusion equation governing the concentration of conservative and passive tracer is derived.Differing from the conventional equation, the equation derived in the present paper reveals the Lagrangian convection and has no need to introduce the artificial hypothesis for the so-called "tidal dispersion".
The theory presented here is base on a three-dimensional weakly nonlinear dynamic system.
1990, (3): 331-342.
Abstract:
In this paper, the depth of the summer thermocline of the South Huanghai Sea and the East China Sea is calculated with two kinds of one-dimentional models, and the formation reasons are explained for the summer thermocline depth distribution characteristics in the study area.It is proved that in the shelf area of the East China Sea, tidal mixing has an important impact on the thermocline depth.And a new explanation for certain phenomena of the so-called coastal upwelling in the East China Sea is proposed.
In this paper, the depth of the summer thermocline of the South Huanghai Sea and the East China Sea is calculated with two kinds of one-dimentional models, and the formation reasons are explained for the summer thermocline depth distribution characteristics in the study area.It is proved that in the shelf area of the East China Sea, tidal mixing has an important impact on the thermocline depth.And a new explanation for certain phenomena of the so-called coastal upwelling in the East China Sea is proposed.
1990, (3): 343-352.
Abstract:
Owing to the fact that the wind speed and direction of typhoon vary rapidly with time and space in typhoon fetch; the nearer to the typhoon eye the greater the wind velocity, and the shorter the wind fetch the smaller the wind time,as a result,the more difficult for the wind wave to fully grow.Hence.in typhoon wave numerical calculation it is impossible to use the model for a fully grown wave spectrum.Lately, the author et at.presented a CHGS method for numerical forecasting of typhoon waves, where a model for the growing wave spectrum was set up (see Eq.(2) in the text).The model involves a parameter indicating the growing degree of wind wave, i.e., the mean wave age β.When βvalue is small, the wave energy is chiefly concentrated near the peak frequency, so that the spectral peak gets hi gh and steep; with the increase of β the spectral shape gradually gets lower and gentler; when β=Ⅰ, the wave fully grows, the growing spectrum becomes a fully grown P-M spectrum.The model also shows a spectral "overshooting" phenomenon within the "balance zone".
Owing to the fact that the wind speed and direction of typhoon vary rapidly with time and space in typhoon fetch; the nearer to the typhoon eye the greater the wind velocity, and the shorter the wind fetch the smaller the wind time,as a result,the more difficult for the wind wave to fully grow.Hence.in typhoon wave numerical calculation it is impossible to use the model for a fully grown wave spectrum.Lately, the author et at.presented a CHGS method for numerical forecasting of typhoon waves, where a model for the growing wave spectrum was set up (see Eq.(2) in the text).The model involves a parameter indicating the growing degree of wind wave, i.e., the mean wave age β.When βvalue is small, the wave energy is chiefly concentrated near the peak frequency, so that the spectral peak gets hi gh and steep; with the increase of β the spectral shape gradually gets lower and gentler; when β=Ⅰ, the wave fully grows, the growing spectrum becomes a fully grown P-M spectrum.The model also shows a spectral "overshooting" phenomenon within the "balance zone".
1990, (3): 353-362.
Abstract:
Using the COADS data set of sea surface temperature in the Equatorial Eastern Pacific, thirty one El Nino events and twenty four anti-El Nino events were identified for the period from 1854 to 1987.The results were compared with those of the other authors.The El Nino events (or anti-El Nino events) are classified into two groups according to the timing of occrrence of the events:one starts at the first half of a year, another begins at the second half of a year.Both 1982-1983 and 1986-1987 events fall into the second group, which are characterized by the eastward migration of the positive anomaly of the sea surface temperature and the significant increasing of the anomaly in September or October.
Using the COADS data set of sea surface temperature in the Equatorial Eastern Pacific, thirty one El Nino events and twenty four anti-El Nino events were identified for the period from 1854 to 1987.The results were compared with those of the other authors.The El Nino events (or anti-El Nino events) are classified into two groups according to the timing of occrrence of the events:one starts at the first half of a year, another begins at the second half of a year.Both 1982-1983 and 1986-1987 events fall into the second group, which are characterized by the eastward migration of the positive anomaly of the sea surface temperature and the significant increasing of the anomaly in September or October.
1990, (3): 363-371.
Abstract:
In this paper, the nonlinear waves and their barotropic stability in the tropical ocean and atmosphere are studied with the qualitative theory of the ordinary differential equation.The relationship is derived between the stability of nonlinear waves with different frequencies and the basic currents and their horizontal shear in the tropical ocean and atmosphere.
In this paper, the nonlinear waves and their barotropic stability in the tropical ocean and atmosphere are studied with the qualitative theory of the ordinary differential equation.The relationship is derived between the stability of nonlinear waves with different frequencies and the basic currents and their horizontal shear in the tropical ocean and atmosphere.
1990, (3): 373-387.
Abstract:
On the basis of the arctic monthly mean sea ice extent data set during 1953-1984, the arctic region is divided into eight subregions,and the analyses of empirical orthogonal functions, power spectrum and maximum entropy spectrum are made to indentify the major spatial and temporal features of the sea ice fluctuations within 32-year period.And then, a brief appropriate physical explanation is tentatively suggested.The results show that both seasonal and non-seasonal variations of the sea ice extent are remarkable, and iis mean annual peripheral positions as well as their interannual shifting amplitudes are quite different among all subregions.These features are primarily affected by solar radiation, ocean circulation, sea surface temperature and maritime-continental contrast, while the non-seasonal variations are most possibly affected by the cosmic-geophysical factors such as earth pole shife, earth rotation oscillation and solar activity.
On the basis of the arctic monthly mean sea ice extent data set during 1953-1984, the arctic region is divided into eight subregions,and the analyses of empirical orthogonal functions, power spectrum and maximum entropy spectrum are made to indentify the major spatial and temporal features of the sea ice fluctuations within 32-year period.And then, a brief appropriate physical explanation is tentatively suggested.The results show that both seasonal and non-seasonal variations of the sea ice extent are remarkable, and iis mean annual peripheral positions as well as their interannual shifting amplitudes are quite different among all subregions.These features are primarily affected by solar radiation, ocean circulation, sea surface temperature and maritime-continental contrast, while the non-seasonal variations are most possibly affected by the cosmic-geophysical factors such as earth pole shife, earth rotation oscillation and solar activity.
1990, (3): 389-403.
Abstract:
The pathway and fate of heavy metals were studied in 10m3 enclosures at Xiamen Bay in 1985.The dissolved metals added are removed rather quickly during the first days, and their half-removal times (t1/2) (d) are as follows:Pb 5.4-5.8, Hg 6.7-14, Zn 11-22, Cu 16-29, and Cd 30-89.Zinc is transferred biologically to particles during phytoplankton bloom.The main Fate of added metals after 27 days is as follows; over 80% Cd and 60% Cu remain in dissolved phase, more than 60% Pb and 50% Hg transfer to settling settlement, while Zn is equally distributed in dissolved phase and settling settlement.The wall uptake is less than 2% of the total metals added.Organic materials play an essential role in the partition and the transfer of heavy metals in water column.Terrigenous and autochthonous particles show different affinities to different metals.Most heavy metals associate weakly with zooplankton.The Binding of Cd, Pb, Zn and Cu to the particles shows distinctive features related to the diagenetic alteration.
The pathway and fate of heavy metals were studied in 10m3 enclosures at Xiamen Bay in 1985.The dissolved metals added are removed rather quickly during the first days, and their half-removal times (t1/2) (d) are as follows:Pb 5.4-5.8, Hg 6.7-14, Zn 11-22, Cu 16-29, and Cd 30-89.Zinc is transferred biologically to particles during phytoplankton bloom.The main Fate of added metals after 27 days is as follows; over 80% Cd and 60% Cu remain in dissolved phase, more than 60% Pb and 50% Hg transfer to settling settlement, while Zn is equally distributed in dissolved phase and settling settlement.The wall uptake is less than 2% of the total metals added.Organic materials play an essential role in the partition and the transfer of heavy metals in water column.Terrigenous and autochthonous particles show different affinities to different metals.Most heavy metals associate weakly with zooplankton.The Binding of Cd, Pb, Zn and Cu to the particles shows distinctive features related to the diagenetic alteration.
1990, (3): 405-411.
Abstract:
Laboratory experiments of bioassay with Pltaeodaetytum tricornutum, Chatoceros didymus, Chaetoreros calcitraus and Heterogtoea sp.sampled from the Changjiang Estuary in spring and summer, 1986, indicated that both N and P limit phytoplankton growth in the medium with N:P ranged between 8-30, and N limits phytoplankton production in the medium with N:P<8, while P is the limitary nutrient in the N:P>30.Generally, N:P in the Changjiang Estuary waters is 2 times higher than Redfield ratio.The bioassay experiments with high N:P water samples collected from Changjiang Estuary show that phytoplankton production is limited by P.Phytopiankton appears to give priority to the uptake of P at all periods of time.And the optimum N:P for phytoplankton growth is determined to be 18.
Laboratory experiments of bioassay with Pltaeodaetytum tricornutum, Chatoceros didymus, Chaetoreros calcitraus and Heterogtoea sp.sampled from the Changjiang Estuary in spring and summer, 1986, indicated that both N and P limit phytoplankton growth in the medium with N:P ranged between 8-30, and N limits phytoplankton production in the medium with N:P<8, while P is the limitary nutrient in the N:P>30.Generally, N:P in the Changjiang Estuary waters is 2 times higher than Redfield ratio.The bioassay experiments with high N:P water samples collected from Changjiang Estuary show that phytoplankton production is limited by P.Phytopiankton appears to give priority to the uptake of P at all periods of time.And the optimum N:P for phytoplankton growth is determined to be 18.
1990, (3): 413-428.
Abstract:
On the basis of the data of geophysics and seismic activities, the analyses of the active faults, seismic activities and the sea floor unstable factors of the Zhujiang River Mouth Basin have been made so as to study the characteristics of the compressional subactive continental margin of Cathaysian system, arc littoral strongly active fracture zone, the division of seismic subzone and seismic zone of the continental margin of northern South China Sea, the potential focal area, and to analyze the regional stability.We consider that the Zhujiang River Mouth Basin belongs to a stable or a moderately stable region.
On the basis of the data of geophysics and seismic activities, the analyses of the active faults, seismic activities and the sea floor unstable factors of the Zhujiang River Mouth Basin have been made so as to study the characteristics of the compressional subactive continental margin of Cathaysian system, arc littoral strongly active fracture zone, the division of seismic subzone and seismic zone of the continental margin of northern South China Sea, the potential focal area, and to analyze the regional stability.We consider that the Zhujiang River Mouth Basin belongs to a stable or a moderately stable region.
1990, (3): 429-438.
Abstract:
This paper deals with species composition, seasonal change and horizontal distribution of the Hydromedusae (Hyd.), Siphonophores (Sip.) and Ctenophores (Cte.) and their relationship to the environmental factors.Materials from 17 stations in the Xiamen Harbour and adjacent waters were taken once monthly for the period from Sep.1980 to Aug.1981.The results indicate that for the dominant species of Phialidium folleatum, Lensia subtiloides and Pleurobrachia globosa, the total annual number of species has one peak and the total annual number of individual has one peak and two secondary peaks.On the basis of their ecological characteristice, the Hydromedusae, Siphonophores and Ctenophores found in the region investigated may be divided into the following ecological groups:estuarine group, neritic group and oceanic group.Their seasonal succession is correlated with the relative intensity of several water systems.
This paper deals with species composition, seasonal change and horizontal distribution of the Hydromedusae (Hyd.), Siphonophores (Sip.) and Ctenophores (Cte.) and their relationship to the environmental factors.Materials from 17 stations in the Xiamen Harbour and adjacent waters were taken once monthly for the period from Sep.1980 to Aug.1981.The results indicate that for the dominant species of Phialidium folleatum, Lensia subtiloides and Pleurobrachia globosa, the total annual number of species has one peak and the total annual number of individual has one peak and two secondary peaks.On the basis of their ecological characteristice, the Hydromedusae, Siphonophores and Ctenophores found in the region investigated may be divided into the following ecological groups:estuarine group, neritic group and oceanic group.Their seasonal succession is correlated with the relative intensity of several water systems.
1990, (3): 439-447.
Abstract:
The development rate of Labidocera euchaeta Giesbrecht in the Xiamen Harbor was studied in laboratory.The results showed that the development times of egg and larval stages (D) were significantly correlated with temperature (TO13), following the Belehradek function, D=α(T-7.5)-1.0634.The development time from egg to larval stages and adult, as well as generation time can be predicted from the equation for egg development (α=411/24) by appropriately multipling the constant (α) with a proportion.The development was not isochronal over the whole larval period.Durations of naupliar stages were short and quasi-isochronal, which favored their non-feeding development.In contrast, durations of copepodid stages (C) were long.CV had the longest duration followed by CI, both of which are considered as the critical stages in the larval development.The acclimation effect of the seasonal temperature on the development rate was also observed.
The development rate of Labidocera euchaeta Giesbrecht in the Xiamen Harbor was studied in laboratory.The results showed that the development times of egg and larval stages (D) were significantly correlated with temperature (TO13), following the Belehradek function, D=α(T-7.5)-1.0634.The development time from egg to larval stages and adult, as well as generation time can be predicted from the equation for egg development (α=411/24) by appropriately multipling the constant (α) with a proportion.The development was not isochronal over the whole larval period.Durations of naupliar stages were short and quasi-isochronal, which favored their non-feeding development.In contrast, durations of copepodid stages (C) were long.CV had the longest duration followed by CI, both of which are considered as the critical stages in the larval development.The acclimation effect of the seasonal temperature on the development rate was also observed.
1990, (3): 449-457.
Abstract:
This study deals with the general numerical model to simulate the two-dimensional tidal flow, flooding wave (long wave) and shallow water waves (short wave).The foundational model is based on nonlinear Boussinesq equations.Numerical method for modelling the short waves is investigated in detail.The forces, such as Coriolis forces, wind stress, atmosphere and bottom friction, are considered.A two-dimensional implicit difference scheme of Boussinesq equations is proposed.The low-reflection outflow open boundary is suggested.By means of this model,both velocity fields of circulation current in a channel with step expansion and the wave diffraction behind a semi-infinite breakwater are computed, and the results are satisfactory.
This study deals with the general numerical model to simulate the two-dimensional tidal flow, flooding wave (long wave) and shallow water waves (short wave).The foundational model is based on nonlinear Boussinesq equations.Numerical method for modelling the short waves is investigated in detail.The forces, such as Coriolis forces, wind stress, atmosphere and bottom friction, are considered.A two-dimensional implicit difference scheme of Boussinesq equations is proposed.The low-reflection outflow open boundary is suggested.By means of this model,both velocity fields of circulation current in a channel with step expansion and the wave diffraction behind a semi-infinite breakwater are computed, and the results are satisfactory.
1990, (3): 459-464.
Abstract:
1990, (3): 465-472.
Abstract:
