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1.
DivisionofhydroclimaticareaoverChinaseas—Ⅱ.ClusteranalysisandfuzzyISODATA.¥ChenShangjiandYaoShiyu(ReceivedAugust1,1993;accept...  相似文献   

2.
The aim of this paper is to study whether the features of perennial summer over the South China Sea remain constant all the year round or not , and whether there are any seasonal differences throughout the year or not. According to the characteristics of remarkable monsoon and frequent typhoon, the influences of monsoon and tropical cyclone on the hydrological features and the seasonal structure over the South China Sea are analysed by using examples. It may be considered that in the perennial summer area over the South China Sea, it is summer all the year round, but it does not remain constant throughout the year. On the basis of index dates of developing stages for winter and summer monsoons as well as the seasonal characteristics of typhoon frequency,the perennial summer season over the South China Sea may be divided into four periods, namely, early summer, midsummer, sweltering summer and late summer. The concrete classification and the hydrological seasonal feature of each period are discussed.  相似文献   

3.
ThechemicalcharacteristicsofaerosolsintheKuroshioarea-Ⅰ.Sourcesandfluxes¥ChenLiqi;YangXulin;TangRongkunandYuQun'(ReceivedFebr...  相似文献   

4.
- Starting from satellite remote sensing data, the dynamical processes of shear waves occurring at the boundary between the western boundary current and the shelf slope water are studied and dynamically analyzed in this study. The average wavelength is 75 km, and the average amplitude (from crest to trough )17 km. the average phase speed 100 cms-1 for the shear waves along the north wall of the Gulf Stream to the east of Cape Hatteras measured from NOAA satellite IR (infrared ) images. The average wavelength of shear waves along the north wall of the Kuroshio Current is 57 km, and the average amplitude 17 km. For the shear waves occurring along the west wall of the Gulf Stream to the south of Cape Hatteras, the average wavelength is 131 km, and the average amplitude 33 km measured from Seasat SAR (synthetic aperture radar )images. The time for one cycle of shear wave event is about one week.In order to explore the dynamical mechanisms of shear waves, we solved the vorticity equation for a stratified flu  相似文献   

5.
Biostatistics (F analysis and Duncan's new multiple range test) combining with numerical and traditional taxonomy is used to report one new species, ( Isis minorbrachyblasta(I. m) ) as well as I. hippuris (I. h) and I. reticulata(I. r) from the China seas. The morphological characters of the spicules and other skeletal structures of each species are illustrated in de-tials with Scanning Electron Micrographs and compared with each other.  相似文献   

6.
By using a method of boundary temperature index of seasons, a classification of hydrological climatic seasons in the China seas is made on the basis statistics of the sea surface air and water temperatures over the years. The results indicate that the assignment of hydrological seasons in the China seas differs with various sea areas. It may be divided into three climatic belts. In the temperate zone area, four seasons are clearly distinct with very long winter. While in the subtropical zone area, there is no winter throughout the year. The autumn is linked together with the spring, and the summer is unusually long. As for the tropical zone area, it is summer all the year round without any other seasons. In addition , the regular pattern of transformation of the four seasons and the regional characteristics of the length of each season are analyzed in greater detail. The results are in agreement with the continental seasonal classification and it is also shown that the results are reasonable and reliabl  相似文献   

7.
The distribution of ostracods and benthonic foraminifers in the China sea area is briefly reviewed from the paleobio-geographic viewpoint in this paper. Three regions can be distinguished in the area on the basis of modern distribution data: Region I (the Huanghai Sea and the Bohai Sea) with cool and temperate forms, Region I (the East China Sea and the northern part of the South China Sea) with subtropical warm-water forms and Region Ⅲ (central and southern parts of the South China Sea) with larger foraminifers and other tropical warm-water forms. The occurrence of Nummulites-Discocyclira fauna in the Eocene deposits of the East China Sea indicates a northward extension of tropical zoogeographical region at the time, whereas the distribution pattern of the Miocene Nephrolepidina-Miogypsiua-Austrotrillina fauna in the South China Sea resembles that of the present larger-foraminiferal fauna. In the South China Sea and Taiwan, a warm-water fauna with Asterorotalia and Pseudorotalia first appeared in late  相似文献   

8.
- In this paper, by using two sets of composite data of developed and undeveloped depressions over the South China Sea, we analyze and compare the dynamic structures, the heating fields and the vorticity budget residuals of two different types of depressions. Our conclusions are as follows:The two types of depressions are similar in thermodynamical and dynamical structures. The main differ ences are : in the high layer of developed depression there is a divergence field, with a center near the zero line of vertical wind shear, and over undeveloped depression, the divergence field is weaker and the vertical wind at its center is greater than 5 m s-1. The thermodynamical field of the former is asymmetrical and that of the latter is quasi - symmetrical. As far as the dynamics structure is concerned, the convergence in the lower layer and the difference of divergence between the upper and lower layers of developed depression is three tmies larger than that of undeveloped depression. The upward motion and he  相似文献   

9.
NumericalstudiesofupwellingincoastalareasoftheEastChinaSea-ⅠThetide-inducedupwellingLuoYiyong,YuGuangyao,HuangZuke(ReceivedOc...  相似文献   

10.
INTRODUCTIONTheattentiontothestudyofmetalsinthemarineaerosolparticulatesisincreasingduetotheirenvironmentalecologicaleffectsandcontributiontothebiogeochemicalcycle.Intheaspectofenvironmentalecologicaleffects,first,onthesideofclimate,aerosolswithmetalscanactascloudcondensationoricenuclei,absorbandscattersolarradiation,andaffecttheradiationbudgetontheearth.Therelativelyhighironcontent(5%)ofthedustcanabsorbtheshortwavelengthradiationefficiently.Second,onthesideofecologicaleffects,di~lvedAlse…  相似文献   

11.
Dynamics of picoplankton in the Nansha Islands area of the South China Sea   总被引:5,自引:0,他引:5  
Dynamics of major picoplankton groups, Synechococcus (Syn), Prochlorococcus (Pro), picoeukaryotes (Euk) and heterotrophic bacteria (Bact) was investigated by flow cytometry for the first time in the Nansha Islands area in the South China Sea. Averaged over the whole investigation area, depth-weighted integrated cell abundance (DWA) of Syn, Pro, Euk and Bact was 1.6 (0.4-5.7)×103, 5.4 (0.1-7.3)×104, 0.7 (0.2-2.2)×103, and 2.3 (1.4-3.2)×105 cells/mL respectively. Picoautotrophic cell abundance was low in the northwest part of the Nansha Islands where surface water temperature was low and the upper mixed layer was shallow. Concurrently, a surface maximum vertical distribution pattern was observed in this area. While in the southeast and east zones where temperatures were relatively higher and nitraclines were deeper, picoplankton is abundant and a subsurface maximum around 50-75 m is observed. Coupling of horizontal and vertical distribution patterns of picoplankton abundance and hydrological status wa  相似文献   

12.
INTRODUCTIONThegenusTetraselmisStein ( 1 878)isagreenflagellates (Prasinophyceae)thatconsistsofmanymarineaswellasafewfreshwaterspecies .Marinespeciesoftenoccurindensepopula tionscausingbloomsintidepoolsorbays ,therebybeingimportanttoanunderstandingofthedynam…  相似文献   

13.
Variations of monsoon wind field in the sea area along the southeastern coast of China during the ENSO events and its influence on the sea level and sea surface temperature (SST) are explored mainly on the basis of the data of monthly mean wind at 850 hPa and five coastal stations during 1973-1987. The results from the analyses of the data and theoretical estimation show that the southwest wind anomalies appeared in the study area during the events, and northeast wind anomalies occurred in general before the events. With the coastline of the area being parallel basically to the direction of the wind, an Ekman transport will result in an accumulation of the water near the coast or a departure of the water from the coast. As a result , the sea level and SST there will be affected markedly. During the events, southwest wind will intensify in the summer, and northeast wind will weaken in the winter. Their total effect is that a large negative anomaly of the sea level and SST will occur. The estimations indi  相似文献   

14.
In this part ot the paper theoretical wind-wave spectra nave been derived oy (I) expressing the spectrum in series composed of exponential terms; (2) assuming that the spectrum satisfies a high order linear ordinary differential equation; (3) introducing proper parameters in the spectrum; and (4) making use of some known charateristics of wind-wave spectrum, for instance, the law governing the equilibrium range. The spectrum obtained contains the zero order moment of the spectrum m0, the peak frequency ω0 and the ratio R =ω/ω0 (ω being the mean zero-crossing frequency) as parameters. The shape of the nondimensional spectrum S(ω) = ω0S(ω)/m0(ω=ω/ω0) changes with R and theoretically reduces to a Dirac delta function δ(ω-1) when R = 1. A spectrum of simplified form is given for practical uses, in which R is replaced by a peakness factor P=S(1).  相似文献   

15.
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 high 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 spect  相似文献   

16.
DoubleKelvinwavesalongtheOkinawaTroughintheEastChinaSea-ⅠAnalyticsolutionsandobservations¥WangJiaandYuanYeli(ReceivedOctober2...  相似文献   

17.
In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of China and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements Cl an  相似文献   

18.
LAGFD-WAM numerical wave model——Ⅰ. Basic physical model   总被引:4,自引:1,他引:4  
The LAGFD-WAM wave model is a third generation wave model. In the present paper the physical aspect of the model was shown in great detail including energy spectrum balance equation, complicated characteristics equations and source functions.  相似文献   

19.
-Exchange additivity of binary mixtures of hydrous metal oxides and clay minerals has been studied by investigating the relations of the zinc exchange-pH and the zinc partition coefficients to mixtures. The additive exchange equation is proposed to describe the exchange-pH relationship. The results suggest that zinc exchanges on the components in amorphous iron oxide/montmorrillonite, kaolinite/montmorrillonite, γ-A100H/montmorrillonite, amorphous iron oxide/illite mixtures are additive. But the exchange ofδ-MnO2/montmorrillonite is much less than its additive exchange. It is also shown that in the case of additive exchange the exchange parameters (Kmix{SOH}Tmix) of the mixtures are equal in weight to the sum of those of each component of the solid mixtures.  相似文献   

20.
In the present paper,the construction and working principle of stone-mill-shaped sievesand elutriation separator for benthos survey are introduced. The stone-mill-shaped sieves are composed of three round screens and a mildde frame.The lowest screen is the biggest in diameter.Compared with the existing square sieves,thestone-mill-shaped sieves have the advantages of preventing losing organisms when sample  相似文献   

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