1990 Vol. 9, No. 4

Physical Oceanography,Marine Meteorology and Marine Physics
A j, υ model for the analysis and prediction of tides
Chen Zongyong, Huang Zuke, Zhou Tianhua, Tang Enxiang, Wang Yuzhou
1990, (4): 475-486.
In this paper, the j,υ corrected formulae of the amplitudes and the phases of 58 astronomical constituents are given, and the models for the analysis and prediction of 169 constituents are presented. The new Cartwright's calculated results of the tidal potential are used, and the quadratic analysis is made. It has been proved by a number of trials that the harmonic constants of constituents are more stable and the accuracy of the predicted result reliable.
A three-dimentional model of the northeast East China Sea, with application to the M2 current field
Tang Yuxiang
1990, (4): 487-498.
A simple three-dimensional tidal model is used to examine the M2 tidal current distribution in a northeastern part of the East China Sea, especially the vertical variation of the current in the region. Computed M2 current is compared with observations available and found to be in good agreement.
Main features of the calculating method in this study are:(1) Vertical variation of the tidal current is taken as a funetion of the depth-mean velocity:(2) the method is applicable to a variety of the vertical eddy viscosities; (3) it has a fine vertical resolution, especially near the sea bootom. So, this method not only enables us to get a steady state solution easily but also depicts effects of the friction on the vertical variation of the current much better.
A numerical study for the coastal upwelling and the coastal front off Zhejiang coast
Liu Xianbing, Su Jilan
1990, (4): 499-512.
A two-dimensional numerical model is constructed to study the interaction between the coastal upwelling and the coastal front off Zhejiang coast in summer. In the f-plane model, the shelf topography, continuous stratification, and Richardson number-dependent eddy coefficients are considered. The results show that the coastal up-welling off Zhejiang in summer can be divided into two regions, the nearshore one (Region A) and the offshore one (Region B). In Region A, the alongshore wind stress has more important effect on the coastal upwelling while in Region B, the upwelling is mainly induced by the Taiwan Warm Current. The results also suggest that the formation of coastal front off Zhejiang in summer is closely related to the strength of the coastal upwelling in Region A.
Marine Meteorology
Analysis of the air-sea heat exchange during the El Nino event in 1983
Zhu Yafen, Yang Dasheng
1990, (4): 513-526.
In this paper,by using the ECMWF objective analysed data as well as CAC and NOAA grid point data of 1981 and 1983,the sensible and latent heat fluxes at the air and sea boundary surface within the range of 45°E-75°W, 35°N-35°S over the Pacific and the Indian Ocean are calculated. The purpose is to analyse the different revealing features during the mature stage and at the end of the 1982-1983 El Nino event and to compare the difference of the features between thd El Nino and the normal. The result shows that the air and sea heat exchange west of the dateline over the central tropical Pacific during the El Nino period is more intense than that of the normal. However,the fluxes of the sensible and latent heat on the sea surface with strong warming of SSTneat by and on the south side of the equator east of 170°W are low and even negative,and the patterns of the sensible and latent heat fluxes over the Indian Ocean during the year of 1983 are similer to that of normal. Spatial patterns of the sensible heat,the latent heat,SST, OLR and the wind speed exhlblt large anomalies during the El Nino event. The corresponding relationships of the spatial distribution of the str. ng exchange of heat fluxes with regions of high SST and action convection of negative anomalies of OLR are relatively complicated. But the region of maximum air and sea heat exchange is in good coincidence with that of high value of the Vs. The strong heat exchange is weakened with the declining and the finishing of the El Nino event in the central tropical Pacific.
The PNA wavetrain and the sea surface temperature in the Northern Pacific
Lin Xuechun
1990, (4): 527-538.
In this paper, the response of the atmospheric 3-5 year cycle to Northern Pacific SST is discussed, The results are as follows:
1. From the simultaneous temporal correlations between the Equatorial Eastern Pacific SST, the westerly dirft area's SST and the Northern Pacific SST at all gridpoints, we find that there are three correlative regions in the Northern Pacific SST field, they are the westerly drift area, the Equatorial Eastern Pacific and the Alaska Bay, and their structures are very similar to the PNA pattern in the atmosphere The difference PTI between the Equatorial Eastern Pacific SST anomaly and the westerly drift area's SST anomaly can indicate the change of the PNA pattern of the Northern Pacific SST anomaly. It can represent SST change of 65% areas over the Northern Pacific and can keep watch on El Nino and un-El Nino.
2. Simultaneous temporal correlative field between PTI and filtered 500hPa (there is 3-5 year cycle only) of the Northern Hemisphere presents clear PNA structure. The responses of the filtered 500hPa to El Nino and to un-El Nino prodace +PNA and-PNA wavetrains respectively.
3. According to the different positions of the sea-surface temperature rise (drop), El Nino (un-El Nino)can be divided into two classes; east-pattern and middle-pattern. The responses of the filtered 500hPa to the east-pattern and to the middle-pattern will produce PNA and EAA wavetrain respectively. This indicates that the responses of the atmosphere to the stationary heat sources in diffrent areas will produce wavetrains in diffrent track.
The effect of unstable inertia-gravity wave on the occurrence and the development of typhoon and tropical cyclone
Niu Xuexin
1990, (4): 539-546.
In this paper,the analysis of the occurrence and the development of typhoon and tropical cyclone is made with the unstable theory of wave. The result indicates that the primary wave is the unstable inertia-gravity wave in the process of the occurrence and the development of typhoon and tropical cyclone:The existence of the deep moist layer and the heating by moisture condensation can impel and intensify the unstability of the wave and is favourable for the reduction of the wave energy dispersion, therefore, it is good for the formation and the development of typhoon and tropical cyclone, and also can slow down the wave speed. Besides, the condition that the change of the specific volume of the basic state with pressure is less than that of adiabatic state may also lead to the wave unstability, thus may have certain effect on the occurrence and the development of typhoon and tropical cyclone.
Marine Chemistry
Study of aquatic chemical characteristic in some bays along the coastal region of Zhejiang Province
Wang Yuheng, Dong Henglin, Jiang Guochang
1990, (4): 547-554.
In this paper,the aquatic chemical characteristics in the Hangzhou Bay,Xiangshan Bay and Leqing Bay along the coastal region of Zhejiang Province are discussed. Results show that the seasonal variations of chemical elements are obvious. The distribution of silicate in Hangzhou Bay and contents of dissolved oxygen and nutrient in the Xiangshan Bay are found to be unusual in winter. Correlations among the elements are complex. The content of nutrient in the Hangzhou Bay is higher than that in Xiangshan Bay and the content of nutrient in the Xiangshan Bay is higher than that in the Leqing Bay. The variation of the ratio of N/P is obvious. This reflects the aquatic chemical characteristics in the bay. Finally, this paper also discusses the reason why the aquatic chemical characteristics in the bays are unusual.
Oscillopolarographic determination of microsillicon in seawater
Chen Liyi
1990, (4): 555-560.
A new oscillopolarographic method for the determination of Si (Ⅳ) is described in this paper. In the system HCl-Sb(Ⅲ)-Mo(Ⅵ)-NaCl-ethyl alcohol, Si (Ⅳ) with Sb (Ⅲ) and Mo (Ⅵ) form ternary heteropoly acid. The anion of ternary heteropoly is adsorbed on the dropping mercury electrobe and under proper electric potentials reduced quickly into heteropoly blue. The process of electrochemical reaction will produce a sensitive polarographic wave with peak potential at -0.30(Vs. SCE). The lower limit of determination is 8×10-8 mol/dm3. This method is sensitive, accurate and extremely rapid for the determination of micro-silicon in seawater.
Marine Geology and Geomorphology
Fossil fauna and transgressive.sequence from core QC2 in the South Huanghai Sea
Zhu Xionghua, Lin Hemao
1990, (4): 561-578.
According to palaeoenvironmental analysis on the fossil fauna dominated by Foraminifera and Ostracoda, core QC2 contains 8 marine transgressive beds, called (from up to bottom) Transgressive Beds Ⅰ,Ⅱ, Ⅲ, …,Ⅷ respectively. Together with dating data, the transgressive sequence since 1.7 Ma B. P. has been established, indicating that the core went through middle and late Early Pleistocene, early and late Middle Pleistocene, early and late (Substages A and B) Late Pleistocene and the Holocene transgressions. Within these 8 transgressions, late Middle Pleistocene, early Late Pleistocene and the Holocene transgressions-had rather strong activities proved by shallow sea (of 50 or 20-50 m water depth) deposits in the prime, while 2 of the 8, during middle Early Pleistocene and late Late Pleistocene (Substage A), were much weaker only with supratidal deposits. The transgressive cycles also differ from each other. Transgressions in the Holocene and in Substage B of late Late Pleistocene are made up of 3 and 2 subcycles of marine ingressions and regressions respectively, but most transgression only have a single ingressive or regressive sequence. With the core, some important problems concerning the study of Quaternary transgression such as correlation of transgressive beds and climatic periods and dating of the transgressive beds are discussed in this paper.
Marine Biology and Fishery
Preliminary study of gonadotropin-releasing analogue (GnRH-A) initiated gonadal development of amphioxus
Fang Yongqiang, Qi Xiang, Liang Ping, Hong Guiying
1990, (4): 579-585.
Amphioxus in the seasonally regressed phase of gonadat development were used in this study. Each sample animal was injected with 40 nanogram of synthetic gonadotropin-releasing hormone analogue (GnRH-A) in distilled water every other day for up to 16 days; control animals received similar volumes of distilled wnter only. Both hormone-treated samples and control animals were examined under microscope every eight days and every twelve days. Then all the animals were killed on the 16th day. Gonads earlier development and a more advanced degree of gametogenesis are in the hormone-treated group than in the control group. Thus, GnRH-A can initiate and accelerate the gonadal development in gonadally regressed amphioxus. GnRH-A in some form may be important in regulating the gonadal development in amphioxus as well as in vertebrates.
Marine Engineering
Application of Monte-Carlo statistical experiments in design of ocean engineering——Estimating the parameters, models and probabilities
Liu Defu, Shi Jiangang, Zhou Zhigang
1990, (4): 587-597.
Recently, some results have been acquired with the Monte-Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long-term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms.
A stability analysis for the sheared oil film contained by the boom
Zhao Wenqian, Jiang Wei, Wu Zhiwei
1990, (4): 599-610.
According to the observation in experiment of stability of the oil film, the assumption of velocity distribution for both the water flow and the oil film is introduced. On the basis of the assumption, Orr-Sommerfeld stability equation is applied to develop the method of determining the critical velocity of the oil film, and the criterion for stability of the oil film is obtained. Meanwhile, a formula describing the relation between the thickness of the oil film and the velocity of the water flow is also given and examined by the laboratory experiment.
Distribution of chlorophyll a, photosynthesis and their relations to the environmental factors in the Central South China Sea
Chen Xingqun, Chen Qihuan, Zhuang Liangzhong
1990, (4): 611-617.
Study on ecology of foulers on buoys in Dianbai, Guangdong, China
Lin Sheng, Huang Zongguo, Li Chuanyan, Zheng Chengxing, Wang Jianjun
1990, (4): 618-621.
Role of mangrove in mercury cycling and removal in the Jiulong Estuary
Lin Peng, Chen Ronghua
1990, (4): 622-624.