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1.
Some numerical experiments have been developed to explain dynamically the mechanism of the formation of the wintertime circulation in the Northern Huanghai Sea and the Bohai Sea. From the results of the numerical experiments with Coriolis parameter having positive and negative values respectively, it is found that the current pattern characterized by flowing into the Bohai Sea in the northern part of the Bohai Straits and flowing out of the Bohai Sea in the southern part of the Bohai Straits is controlled basically by the bottom topography with "the deepness on the northern side and shallowness on the southern side'in the Bohai Straits, and is not related to Coriolis parameter having positive and negative values. It also shows that the Huanghai Warm Current regarded as the inllow condition passing through the in-ports at the water boundary of the numerical experiments only influences the region near the water boundary and the eastern region of the Northern Huanghai Sea. In addition, the mechanism of the  相似文献   

2.
Based on the recent research results on dry and wet deposition of nutrient elements and sulphate,we estimate the atmospheric flux of nutrient elements and sulphate to the southern Yellow Sea and the East China Sea in each season.The results suggest that the concentrations of nutrient elements and sulphate in aerosol and precipitation show an apparent seasonal cycle with the maximum values in winter and the minimum values in summer.Depositions of nitrate and sulphate are dominated by wet deposition,while the deposition for phosphate is mainly dry deposition.Moreover,compared with the riverine inputs,the atmospheric deposition may be the main source of dissolved inorganic nutrients in the southern Yellow Sea and the East China Sea.  相似文献   

3.
《Marine Geology》1999,153(1-4):275-302
Detailed interpretation of single-channel air-gun and deep-tow boomer profiles demonstrates that the Marmara Sea, Turkey, experienced small-amplitude (∼70 m) fluctuations in sea level during the later Quaternary, limited in magnitude by the sill depth of the Strait of Dardanelles. Moderate subsidence along the southern shelf and Quaternary glacio-eustatic sea-level variations created several stacked deltaic successions, separated by major shelf-crossing unconformities, which developed during the transitions from global glacial to interglacial periods. Near the Strait of Dardanelles, a series of sand-prone deposits are identified beneath an uppermost (Holocene) transparent mud drape. The sandy deposits thicken into mounds with the morphology and cross-sectional geometries of barrier islands, sand waves, and current-generated marine bars. All cross-stratification indicates unidirectional flow towards the Dardanelles prior to the deposition of the transparent drape which began ∼7000 years BP, in strong support of the notion that the Marmara Sea flowed westwards into the Aegean Sea through the Dardanelles at times of deglaciation in northern Europe. The global sea-level curve shows that, at ∼11,000 and ∼9500 years BP, sea level rose to the sill depths of the Straits of Dardanelles and Bosphorus, respectively. The effect from ∼11,000 to ∼9500 years BP was seawater incursion into the Marmara Sea, drowning and formation of algal-serpulid bioherms atop lowstand barrier islands, and transgression of shelves and lowstand deltas. At ∼9500 years BP, glacial meltwater temporarily stored in the Black Sea lake, developed into a vigorous southward flow toward the Aegean Sea, forming west-directed sandy bedforms in the western Marmara Sea and initiating deposition of sapropel S1 in the Aegean Sea. This strong outflow persisted until ∼7000 years BP, after which a mud drape began to accumulate in the Marmara Sea and euryhaline Mediterranean mollusks successfully migrated into a progressively more saline Black Sea where sapropel deposition began. Most eastern Mediterranean sapropels from S1 to S11 appear to correlate with periods of rising sea level and breaching, or near-breaching, of the Bosphorus sill. These events are believed to coincide with times of vigorous outflow of low-salinity (?fresh) surface waters transiting the Black Sea–Marmara Sea corridor, and ultimately derived from melting of northern European ice sheets.  相似文献   

4.
In this paper, the low-frequency fluctuations of sea level and their relationship to atmospheric forcing along the coasts of the Huanghai Sea and the East China Sea are studied. Spectrum analyses are made for the time series of daily mean sea level, atmospheric pressure and wind stress at seven coastal stations. It is found that at all the stations, the main part of the energy of the sea level fluctuations, within the (2-60)-day period, is concentrated on the (12-60)-day period band and that an obvious spectral peak appears at the 3-day period. Along the coast of the Huanghai Sea, variations in the sea level are greater in winter than in summer. In winter, along the coasts of the Huanghai Sea and the East China Sea there is a kind of sea level fluctuations propagating southwards. Among the many factors causing sea level variation, the most obvious one is atmospheric pressure, followed next by the alongshore wind stress.  相似文献   

5.
ModellingofthebarotropicprocessesintheBohaiSea¥HuangDaji;ChenZongyongandSuJilan(SecondIngtituteofOceanography,StateOceanicAdm...  相似文献   

6.
- 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.  相似文献   

7.
Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 duringJune of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimen-sional non-linear diagnostic, semidiagnostic models and prognostic in the σ coordinate. The computed re-sults show that the density and velocity fields and so on have been adjusted when time is about 3 days,namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed re-gion, the Huanghai coastal current flows southeastward, and then it flows out the computed region southof Cheju Island. In the west side of the southern part of the computed region, there is other current,which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to thenortheast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Is-land, and it has characteristics of high density and low temperature. There is an offshore branch of Tai-wan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows north-eastward. The Kuroshio in the East China Sea is stronger, and flows northeastward. Its maximum hori-zontal velocity is 108.5 cm/s at the sea surface, which is located at the northern boundary, and it is106.1 cm/s at 30 m level, 102.2 cm/s at 75 m level and 85.1 cm/s at 200 m level, respectively, whichare all located at the southern boundary. Comparing the results of diagnostic calculation with those ofsemidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively,and there is a little difference between them in quantity. The comparison between the computed veloci-ties and the obeered velocities at the mooring station show that they agree each other.  相似文献   

8.
On the basis of perennial monthly mean temperature and salinity data, the classification of monthly water masses at the surface and the bottom in the Bohai Sea, the Huanghai Sea and the East China Sea, has been made by using the method of fuzzy cluster from the modified characteristic of water masses in the shallow water area. In this paper, the basic features, growth and decline patterns of water masses in relation to fishing grounds in the whole shelves of the Bohai Sea, the Huanghai Sea and the East China Sea are discussed with emphasis.  相似文献   

9.
ApplicationofthefourmodelsofdirectionalspectraintheBohaiSea¥WuXiujieandTengXuechun(FirstInstituteofOceanography,StateOceanicA...  相似文献   

10.
Simulation of the seasonal thermal structure in the Bohai Sea   总被引:1,自引:0,他引:1  
The seasonal thermal structure in the Bohai Sea are examined with a three-dimensional boroclinic primitive equation model for shelf sea.The evolution of the seasonal thermal stratification is well simulated.The stratification appears early in April,first in the area off Qinhuangdao and it is well developed in the middle of May.It intensifies with synoptic and neap-spring fluctuations throughout the summer and reaches its maximum in the middle of July.Eventually,it is destroyed at the end of September.There are cold water belts between well-mixed and stratified regions.They are loGated on the mixed side of tidal fronts,and coincide with the isolines for a temperature difference of 1-2℃ between surface and bottom.The sea surface temperature (SST) distribution shows local maxima at the head of three bays and to the south of Qinhuangdao during the summer.The Bohai Sea responds to the variability in the atmospheric forcing and in tides with the synoptic and neap-spring variations of SST,as well as in the stratification and in variable positions of tidal fronts.  相似文献   

11.
Simulation of the seasonal thermal structure in the Bobal SeaHuangDaji;SuJilan;andChenZongyong(RecrivedMay21,1995;acceptedJun...  相似文献   

12.
Mironov  A. N.  Dilman  A. B.  Minin  K. V.  Malyutina  M. V. 《Oceanology》2019,59(6):920-930
Oceanology - The bathymetric ranges of the same deep-sea (>2000 m) species in the Sea of Japan and outside it are compared. Among 85 deep-sea species of the Sea of Japan mega- and...  相似文献   

13.
IdentificationofbiomarkersofcoresfromtheSouthChinaSea¥TangYunqianandLiuKewen(ReceivedAM10,1994;acceptedJuly5,1994)(SecondInst...  相似文献   

14.
EcologicalcharacteristicsofOstracodaintheSouthHuanghaiSeaandEastChinaSea¥ChenRuixiangandLinJinghong(ThirdInstituteofOceanogra...  相似文献   

15.
The biomasses of fishes at the bottom layer of the Bohai Sea are extimated by analysing the data on samples (447 hauls,more than 0.2 million in number or 20 t in weight of fishes) collected monthly by our institute from April, 1982 to May, 1983 by a pair of bottom trawls through the Bohai Sea. The exploitation problems are also discussed in this paper.  相似文献   

16.
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   

17.
ArestudyofostracodeassemblagesinthesurfacesedimentsoftheHuanghaiSea¥ZhouBaochun;ZhaoQuanhong;HuangWeiandGaoJianxi(Departmento...  相似文献   

18.
- On the basis of the fact that the sharp thermocHne in the Bohai Sea and the northern Huanghai Sea is often distributed in the deep valley areas, it has been long thought that the reason of the formation of the sharp thermocHne is that the cold water can be easily kept in valleys. But recent investigations carried out in the southern Huanghai Sea in summer show that all of the sharp thermocHne areas were distributed in the shallow sloping-bottom areas but not in the deep valley areas. Only in autumn would the sharp thermoclines translate to the deep valley areas. In summer, they are characterized by shallow upper mixing layer and thin thickness in the southern Huanghai Sea. In addition to entrainment coming from lower boundary of upper mixing layer the entrainment from upper border of bottom homogeneous layer induced by tidal mixing also plays an important role in the growth and decay of thermoclines in these seas.  相似文献   

19.
Quaternary marine ostracoda on the west coast of the Bohai Sea   总被引:1,自引:0,他引:1  
According to the results of analysis of the marine ostracoda biofacies from over 160 drilled holes on the west coast of the Bohai Sea, i.e. Hebei and Shandong Provinces, Tianjin, and the east part of Beijing, the present paper is a discussion of their palaeoecological and stratigraphigical significance. The investigation of ostracoda thanatocoenoces in the modern coastal zone suggests that the distribution of marine ostracoda has been controlled by the salinity and depth of water. The study of Quaternary marine ostracoda should be concentrated mainly on the determination of their biofacies and palaeogeographigical conditions, so as to provide evidence for the determination of transgression range, palaeoshoreline and sca-leve! changes.  相似文献   

20.
In this paper, numerical modelling of the fluctuation of the thermocline in the Bohai Sea has been made using a two-dimensional nonlinear model in stratified ocean and the model for the depth of the thermocline under the effects of wind stirring. The computed results depict the variations of the fluctuation of the thermocline driven by different kinds of wind fields. The fluctuation of the thermocline in the Bohai Sea varies somewhat with different directions, paths and locations of typhoon (cyclone). Under the effects of strong wind, the thermoclines both sink due to mixing and fluctuate. Furthermore, the fluctuation of the thermocline speeds up mixing. At last, the thermoclines disappear after 12-15 h when the strong wind increases from Force 6 to Force 9.  相似文献   

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