1999 Vol. 21, No. 4
Display Method:
1999, 21(4): 1-13.
Abstract:
Under the spherical coordinate,a new 3-D semi-implicit numerical model,considering the tide-producing potential,is developed simulate simulate M2 tides and tidal currents in the Isohai Sea,the Huanghai Sea and the East China Sea.The conyutanonal results cointide with the observed M2 tide in these seas.Compared with 65 gauge stations,it is slxnxm that the averaged absolute difference between the simulated and the observed amplitudes is only 6.4 cm; the averaged difference of phase-lags is 6.4°.The calculated M2 tidal chart consists with Fang's chart(1986) which was drawn based on both numerical and observational results.Compared with 47 current station,the averaged absolute deviation between the calculated and observed harrrpnic constant,Ucosζ、Usinζ、Vcosη、Vsinη of vdal currents at different water layers are from 2.6 cm/s to 4.9 cm/s.The calculated vertical structures of tidal currents are also in fairly good agreement with the observed results.It is the first time to reveal that the current-antphidnxmc points at different layers are lcxated at the same horiwntal poition.The dissipation of M2 tidal energy is also given.
Under the spherical coordinate,a new 3-D semi-implicit numerical model,considering the tide-producing potential,is developed simulate simulate M2 tides and tidal currents in the Isohai Sea,the Huanghai Sea and the East China Sea.The conyutanonal results cointide with the observed M2 tide in these seas.Compared with 65 gauge stations,it is slxnxm that the averaged absolute difference between the simulated and the observed amplitudes is only 6.4 cm; the averaged difference of phase-lags is 6.4°.The calculated M2 tidal chart consists with Fang's chart(1986) which was drawn based on both numerical and observational results.Compared with 47 current station,the averaged absolute deviation between the calculated and observed harrrpnic constant,Ucosζ、Usinζ、Vcosη、Vsinη of vdal currents at different water layers are from 2.6 cm/s to 4.9 cm/s.The calculated vertical structures of tidal currents are also in fairly good agreement with the observed results.It is the first time to reveal that the current-antphidnxmc points at different layers are lcxated at the same horiwntal poition.The dissipation of M2 tidal energy is also given.
1999, 21(4): 14-20.
Abstract:
Based upon honguet-Higgins's nonlinear model of randan sea waves,the joint statistical distribution of isotopic,surface slopes exact to the third-order is derived.It is shown that the joirn distribution of surface slopes has the form of truncated Gram-Charlier seties.The trtutcated terms are decided by the order of approximation to nonlinearity of sea waves.For each order appteuumatiorr,the coefficients in the series are modified comparatively to the cosesponding ones for the previous order apprardrnation.The distribution reduces to Gaussian if the effeM of nonlinear wave-wave couplinK tnteraction is excluded.
Based upon honguet-Higgins's nonlinear model of randan sea waves,the joint statistical distribution of isotopic,surface slopes exact to the third-order is derived.It is shown that the joirn distribution of surface slopes has the form of truncated Gram-Charlier seties.The trtutcated terms are decided by the order of approximation to nonlinearity of sea waves.For each order appteuumatiorr,the coefficients in the series are modified comparatively to the cosesponding ones for the previous order apprardrnation.The distribution reduces to Gaussian if the effeM of nonlinear wave-wave couplinK tnteraction is excluded.
1999, 21(4): 21-26.
Abstract:
Phase space theory is used to analyze the day SST of equatorial local area and nine moving average cn}th air temperature of Qingdao(NNIAMAT).The results show that the correlation dimension and embedding dimension of NMAMAT and SST are 5.83,8,3.93(anti-El Niňo) or 4.37(El Niňo),11(anti-El Niňo) or 9(El Niňo),respectively.Ihe SST of El Niňo and anti-El Niňo can be described as chaotic phenanenon.The correlation dimension increase and embedding dimension decrease of El Niňo SST slaw that the SST iner-structure during El Niňo period is oanplex and implies nonlinear interaction increase.The above parameters and the forecast method of simplex projection operator are used to predict the time series date of SST and NMAMAT,and the biggest prediction relative etaots ad SST and NMAMAT are 0.42%,7.4% within the first eight points,respectively.
Phase space theory is used to analyze the day SST of equatorial local area and nine moving average cn}th air temperature of Qingdao(NNIAMAT).The results show that the correlation dimension and embedding dimension of NMAMAT and SST are 5.83,8,3.93(anti-El Niňo) or 4.37(El Niňo),11(anti-El Niňo) or 9(El Niňo),respectively.Ihe SST of El Niňo and anti-El Niňo can be described as chaotic phenanenon.The correlation dimension increase and embedding dimension decrease of El Niňo SST slaw that the SST iner-structure during El Niňo period is oanplex and implies nonlinear interaction increase.The above parameters and the forecast method of simplex projection operator are used to predict the time series date of SST and NMAMAT,and the biggest prediction relative etaots ad SST and NMAMAT are 0.42%,7.4% within the first eight points,respectively.
1999, 21(4): 27-34.
Abstract:
During twice untypical El Niňo events,the central westem equatorial Pacifict part of the Walker circulation wad weaken apparently,the central eastern equatorial Pacifc part of the HIadley ctrculation was strengthened apparently.The a nomaly of west wind stress in the western equatorial Pacific was strengthened and extended easward,while thu anommly of north wind stress in the eastern equatorial Pacifie was strengthened and extended southward.Ihe energy of warm pool in the western Pacific may be transported eastward in the ways:the equatorial Kelvin wave themncline model and current model.The total energy which was transported eastward by the themtocline model was more than that by the current model.During the 1982-1983 El Niňo event,the equatorial Kelvin wave themocline model played the main role,EUC was weaken.During the 1986-1987 El Niňo event,the equatorial Kelvin wave current model played the main role,EUC was strengthened.During the twice El Niňo events,the phenanenon of EUC's disappearance and reversion was a local ocean response,is didn't propagate eastward with the equatorial Kelvin wave.
During twice untypical El Niňo events,the central westem equatorial Pacifict part of the Walker circulation wad weaken apparently,the central eastern equatorial Pacifc part of the HIadley ctrculation was strengthened apparently.The a nomaly of west wind stress in the western equatorial Pacific was strengthened and extended easward,while thu anommly of north wind stress in the eastern equatorial Pacifie was strengthened and extended southward.Ihe energy of warm pool in the western Pacific may be transported eastward in the ways:the equatorial Kelvin wave themncline model and current model.The total energy which was transported eastward by the themtocline model was more than that by the current model.During the 1982-1983 El Niňo event,the equatorial Kelvin wave themocline model played the main role,EUC was weaken.During the 1986-1987 El Niňo event,the equatorial Kelvin wave current model played the main role,EUC was strengthened.During the twice El Niňo events,the phenanenon of EUC's disappearance and reversion was a local ocean response,is didn't propagate eastward with the equatorial Kelvin wave.
1999, 21(4): 35-42.
Abstract:
By use of cluster analysis in this paper,the monthly averaged SST of the North Pacific is objectively gouged into ten types that have the totally changing characteristics mainly with the changing artanalies of the Mid-East Equatorial Pacific.We can group them into El Niňo-type and La Niňa-type according to the ENSO pherxmerxm.These two types include typical field,non-typical field and three transitional fields.The typical one has the good persistence and fits correctly the EI Nino and La Niňa occurring from 1951 to 1996.Within half a year,there is not inter-conversion between the two typical fields;however,the non-typical field compensates to typical one when it enhances or weakens.The transitional type persists poorly.It is rarely possible for the same transitional types to inter-converse.The main transitional types for conversing are Type 3 and Type 9.By using the type the presern SST field belongs to plus the change of index,it is expelled to predict the beginning and the declination of El Niňo from 1 to 2 months in advance.
By use of cluster analysis in this paper,the monthly averaged SST of the North Pacific is objectively gouged into ten types that have the totally changing characteristics mainly with the changing artanalies of the Mid-East Equatorial Pacific.We can group them into El Niňo-type and La Niňa-type according to the ENSO pherxmerxm.These two types include typical field,non-typical field and three transitional fields.The typical one has the good persistence and fits correctly the EI Nino and La Niňa occurring from 1951 to 1996.Within half a year,there is not inter-conversion between the two typical fields;however,the non-typical field compensates to typical one when it enhances or weakens.The transitional type persists poorly.It is rarely possible for the same transitional types to inter-converse.The main transitional types for conversing are Type 3 and Type 9.By using the type the presern SST field belongs to plus the change of index,it is expelled to predict the beginning and the declination of El Niňo from 1 to 2 months in advance.
1999, 21(4): 43-46.
Abstract:
The relation between the dynamics of phytoplanktan aad essential environmental factors of seawater has been studied.According to the cattparisons between environmental factors of seawater,and on the basis of mathematical space theory and the four principles of normalization,even syrranetry,globality and proximity,smoothing discrete function,the grey derivative and the grey differential equation have been defined,the grey models and relation to the factors(the seawater phiysical and chemical factors) are estimated.The calculated results indicate that rpoplanktom,Mn,Fe and dissolved oxygen are the most important factors.
The relation between the dynamics of phytoplanktan aad essential environmental factors of seawater has been studied.According to the cattparisons between environmental factors of seawater,and on the basis of mathematical space theory and the four principles of normalization,even syrranetry,globality and proximity,smoothing discrete function,the grey derivative and the grey differential equation have been defined,the grey models and relation to the factors(the seawater phiysical and chemical factors) are estimated.The calculated results indicate that rpoplanktom,Mn,Fe and dissolved oxygen are the most important factors.
1999, 21(4): 47-53.
Abstract:
Based on the surveying data of the project "China-Korea Joint Research on Seawater Circuiation and Mass Flwc in the Huanghai Sea"(1996-1997),the hoaizental distribution features and seasonal variations of dissolved oxygert in the whole southem Huanghai Sea are disctssed.The factors such as the Huatghai Sea Warm Current,the Taiwan Warm Current,the Huanghai Sea cold water mass,coastal curmats and Photosynthesis and aganic deoanposition,which influence the contents and distributions of dissolved oxygen are discussed.
Based on the surveying data of the project "China-Korea Joint Research on Seawater Circuiation and Mass Flwc in the Huanghai Sea"(1996-1997),the hoaizental distribution features and seasonal variations of dissolved oxygert in the whole southem Huanghai Sea are disctssed.The factors such as the Huatghai Sea Warm Current,the Taiwan Warm Current,the Huanghai Sea cold water mass,coastal curmats and Photosynthesis and aganic deoanposition,which influence the contents and distributions of dissolved oxygen are discussed.
1999, 21(4): 54-61.
Abstract:
The distribution of 224Ra in the jiulong estuarine waters has been investigated.The results show that 224Ra is non-conservative in this estuary,just as the other estuaries of the world.Varition of 224Ra activities with salinities is examined and 224Ra-S relationship is affected obviously by the seasons.The maxina of dissolved 224Ra in the jiulong estuarine waters is(37.7±1.6)Bq/m3(s=15.57) during spring and(37.7±0.2)Bq/m3(s=18.68) during winter.Based on dissloved 224Ra data,the current speeds of the jiulong estuarine waters seaward are estimated as 2.5 cm/s in summer and 0.91cm/s in winter.
The distribution of 224Ra in the jiulong estuarine waters has been investigated.The results show that 224Ra is non-conservative in this estuary,just as the other estuaries of the world.Varition of 224Ra activities with salinities is examined and 224Ra-S relationship is affected obviously by the seasons.The maxina of dissolved 224Ra in the jiulong estuarine waters is(37.7±1.6)Bq/m3(s=15.57) during spring and(37.7±0.2)Bq/m3(s=18.68) during winter.Based on dissloved 224Ra data,the current speeds of the jiulong estuarine waters seaward are estimated as 2.5 cm/s in summer and 0.91cm/s in winter.
1999, 21(4): 62-69.
Abstract:
The sediment accumulation and the accumulated sediment resuspension in the mouth-bar area under the hydrodynamic environment of the Changjiang Estuary are the major mechanism of the turbidity formation.The sediment accumulation has both mechanisms of the runoff and the tidal current interaction and the salt and fresh-water mixing,the former froms the tidal turbidity,and the latter forms the salt water turbidity marcimum.The turbidity maximum of the Changjiang Estuary belongs to co-turbidity maximun with both tide and salt mechanises.
The sediment accumulation and the accumulated sediment resuspension in the mouth-bar area under the hydrodynamic environment of the Changjiang Estuary are the major mechanism of the turbidity formation.The sediment accumulation has both mechanisms of the runoff and the tidal current interaction and the salt and fresh-water mixing,the former froms the tidal turbidity,and the latter forms the salt water turbidity marcimum.The turbidity maximum of the Changjiang Estuary belongs to co-turbidity maximun with both tide and salt mechanises.
1999, 21(4): 70-77.
Abstract:
Algorithm of optimum oblique canposition factor analysis is intraluced.It includes three procedures:Q-factor analysis,composition tnmsfomung and optimum oblique transforming.It can derive out factors which are canposition andltonnegative.,It is not only adaptable to sample classification,but also to parting end-members fran sulanaritte sediments.Finally,the method is darnnsaated on Okinawa Trough submarine sediment data sets,Changjiang origin end-member is parted out firm those data sets successfully.The method is also adaptable to petrolog,pedology and water pollution study.
Algorithm of optimum oblique canposition factor analysis is intraluced.It includes three procedures:Q-factor analysis,composition tnmsfomung and optimum oblique transforming.It can derive out factors which are canposition andltonnegative.,It is not only adaptable to sample classification,but also to parting end-members fran sulanaritte sediments.Finally,the method is darnnsaated on Okinawa Trough submarine sediment data sets,Changjiang origin end-member is parted out firm those data sets successfully.The method is also adaptable to petrolog,pedology and water pollution study.
1999, 21(4): 78-86.
Abstract:
Based on the investigation materials of 6 cruises in the waters north of Taiwan,OW a from 1987-1990,the abundance distribution characteristics of planktonic copepods are discussed.The results show that the highest abundance of copepods occurs in spring and the lowest one in winter,while the abundance in summer and autumn is between the above two seasons.The copepod abundance in inside of the Kuroshio front is higher than that in outside of the front.There is a distribution tendency that higher abundance occurs in outshore area in summer and in nearshore area in winter,which corresponds with the trend of seasonal swings of the Kuroshio front.The higher copepod abundance appears generally in mixed areas of various water masses,especially in nearshore side of upwelling of the Kumshio subsurface water.However,in the Kuroshio subsurface main water,the abundance is low because of some factors such as law concentration of dissolved oxygen and so on.The vertical distribution trend is that the copepod abundance decreases with increase of depth,and the diurnal vertical migration regularities of some species are probably the one of reasons that cause the abnomal distributions in some local waters.
Based on the investigation materials of 6 cruises in the waters north of Taiwan,OW a from 1987-1990,the abundance distribution characteristics of planktonic copepods are discussed.The results show that the highest abundance of copepods occurs in spring and the lowest one in winter,while the abundance in summer and autumn is between the above two seasons.The copepod abundance in inside of the Kuroshio front is higher than that in outside of the front.There is a distribution tendency that higher abundance occurs in outshore area in summer and in nearshore area in winter,which corresponds with the trend of seasonal swings of the Kuroshio front.The higher copepod abundance appears generally in mixed areas of various water masses,especially in nearshore side of upwelling of the Kumshio subsurface water.However,in the Kuroshio subsurface main water,the abundance is low because of some factors such as law concentration of dissolved oxygen and so on.The vertical distribution trend is that the copepod abundance decreases with increase of depth,and the diurnal vertical migration regularities of some species are probably the one of reasons that cause the abnomal distributions in some local waters.
1999, 21(4): 87-91.
Abstract:
The range of salinity tolerance of the southern bay scallop.A.radians concentrycus was studied in laboratary.All experimenu were carried out with the spats,15-21 mm in height,by exposing the spats to various salinities for periods of 48h or more,with the aim of explaining the observations about the mortality in nature and deciding the farming sites for this species culture.The survival range of salinity is 18.5-44.4 at 16 and 24℃.The effect of lower salinity on the survival rate is more obvious.The salinity range for growth of the spats is 21.2-41.0(the daily growth rate,r > 4.0),suitable 24.0-32.0(r > 8),and optimal 26.0-28.0.If the salinity fluctuates strongly,the survival rate decreases seriously when the salinity is close to threshold value.The salinity tolerance of the scallop relates of the envitaanental salinity,too.The species is more resistant to salinity variation at decreasing temperature in a short time,but cannot increase its tolerance range in the lasting time.Results show that the species can survive and normally grow in the sourhem China seaarea,but it is unsuitable to planting in the estuary or the faming areas when the scallops may expose to freshwater.
The range of salinity tolerance of the southern bay scallop.A.radians concentrycus was studied in laboratary.All experimenu were carried out with the spats,15-21 mm in height,by exposing the spats to various salinities for periods of 48h or more,with the aim of explaining the observations about the mortality in nature and deciding the farming sites for this species culture.The survival range of salinity is 18.5-44.4 at 16 and 24℃.The effect of lower salinity on the survival rate is more obvious.The salinity range for growth of the spats is 21.2-41.0(the daily growth rate,r > 4.0),suitable 24.0-32.0(r > 8),and optimal 26.0-28.0.If the salinity fluctuates strongly,the survival rate decreases seriously when the salinity is close to threshold value.The salinity tolerance of the scallop relates of the envitaanental salinity,too.The species is more resistant to salinity variation at decreasing temperature in a short time,but cannot increase its tolerance range in the lasting time.Results show that the species can survive and normally grow in the sourhem China seaarea,but it is unsuitable to planting in the estuary or the faming areas when the scallops may expose to freshwater.
1999, 21(4): 92-95.
Abstract:
Three new species of Euphysorn genus(Hydrozoa:Anthanedusae,Corymorphidae) from near seas of China are described in great detail.All type specimens are deposited in the Department Ckeanography.Xiamen University.(1) Euphysora brunnescentis sp.nov.Umbrella nearly spherical; exumbrella surface smooth:with sickle-shaped nematocys pedalia in three rudimentary non-tentacular bulbs and with 6-8 brown pigment spots on their adaxial clusters.(2)Euphysora knides sp.now.Exumbrella with scattered nematocyst clusters,without wart processes and pigments; the three rudimentary tentaular bulbs papilla-like,without pigment spots,top of nematocyst conical.Euphysora solidonema sp.All tentacular bulbs extending to both lateral sides,forming thick umbrella margin;principal tentacle short and stiff,with over 10 circular nematocysts and a large terminal nematocyst knob.
Three new species of Euphysorn genus(Hydrozoa:Anthanedusae,Corymorphidae) from near seas of China are described in great detail.All type specimens are deposited in the Department Ckeanography.Xiamen University.(1) Euphysora brunnescentis sp.nov.Umbrella nearly spherical; exumbrella surface smooth:with sickle-shaped nematocys pedalia in three rudimentary non-tentacular bulbs and with 6-8 brown pigment spots on their adaxial clusters.(2)Euphysora knides sp.now.Exumbrella with scattered nematocyst clusters,without wart processes and pigments; the three rudimentary tentaular bulbs papilla-like,without pigment spots,top of nematocyst conical.Euphysora solidonema sp.All tentacular bulbs extending to both lateral sides,forming thick umbrella margin;principal tentacle short and stiff,with over 10 circular nematocysts and a large terminal nematocyst knob.
1999, 21(4): 96-105.
Abstract:
Along with the developrnem of coastal economic bank,the problems of hydrodynamics in estuary area,such as the silting up of waterway,evolution of estuary area,the construction of harbour and the pollution problems,are being brought to one's attention.Numerica simulation method is one of the ideal tools to study such problem.But owing to the complicated shapes of the coastal lines of estuary area and with many islands in the region,it is very difficult to make the discretion of the region of the model.For this reason,the generation method of adaptive mesh is applied to the numerical research of estuary and harbour regions,e.g.,the simulation of hydrodynamic for the Changjiang Estuary and the Hangzhou Bay,Which overcomes,the difficulties of boundary fitting when using regular mesh,and gives raasonable results.
Along with the developrnem of coastal economic bank,the problems of hydrodynamics in estuary area,such as the silting up of waterway,evolution of estuary area,the construction of harbour and the pollution problems,are being brought to one's attention.Numerica simulation method is one of the ideal tools to study such problem.But owing to the complicated shapes of the coastal lines of estuary area and with many islands in the region,it is very difficult to make the discretion of the region of the model.For this reason,the generation method of adaptive mesh is applied to the numerical research of estuary and harbour regions,e.g.,the simulation of hydrodynamic for the Changjiang Estuary and the Hangzhou Bay,Which overcomes,the difficulties of boundary fitting when using regular mesh,and gives raasonable results.
1999, 21(4): 106-113.
Abstract:
The concept of equivalent uniform current is presented.Inorder to deal with the problem of interaction between wave and nonumiform current the nonuriform current can approximately be treated as the equivalent unifomm current by this method.It is simplified to compute the wave and current which are arbitrary varying along water depth.The wave-current forces on small vertical cylinder have been calculated and the results are consistent with the precise solutions very well.
The concept of equivalent uniform current is presented.Inorder to deal with the problem of interaction between wave and nonumiform current the nonuriform current can approximately be treated as the equivalent unifomm current by this method.It is simplified to compute the wave and current which are arbitrary varying along water depth.The wave-current forces on small vertical cylinder have been calculated and the results are consistent with the precise solutions very well.
1999, 21(4): 114-120.
Abstract:
A new method is presented for separating oblique incident waves and reflected waves from coastal structures.The waves may be regular and the wave direction and the wave direction may be arbitrary.The technique is applicable to two wave gauges under a certain limitation.Two and three-dimensional model tests have been done for vertical structures with and without air chambers.The results show that the method can he used to separate the refected waves from the incident waves.
A new method is presented for separating oblique incident waves and reflected waves from coastal structures.The waves may be regular and the wave direction and the wave direction may be arbitrary.The technique is applicable to two wave gauges under a certain limitation.Two and three-dimensional model tests have been done for vertical structures with and without air chambers.The results show that the method can he used to separate the refected waves from the incident waves.
1999, 21(4): 121-124.
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1999, 21(4): 125-130.
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1999, 21(4): 131-135.
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1999, 21(4): 136-141.
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