1992 Vol. 11, No. 2
Display Method:
1992, (2): 157-178.
Abstract:
In the first part of the present paper we have explained why we manage to formulate another wave prediction model when so many of them, including the so-called third generation model, have already been in use. The wind-wave part of the proposed model has also been given. Now we proceed to discuss the swell part,the implementation of the model as a prediction method,mumerical experiments done with ideal wind fields and hindcasts made in the Bohai Sea,in the neighboring seas adjacent to China and in the Northwest Pacific.
In the first part of the present paper we have explained why we manage to formulate another wave prediction model when so many of them, including the so-called third generation model, have already been in use. The wind-wave part of the proposed model has also been given. Now we proceed to discuss the swell part,the implementation of the model as a prediction method,mumerical experiments done with ideal wind fields and hindcasts made in the Bohai Sea,in the neighboring seas adjacent to China and in the Northwest Pacific.
1992, (2): 179-188.
Abstract:
Drift current induced by wind and waves is investigated with phase-averaged Navier-Stokes equation in which the Reynolds stress is closed by k-ε model. The governing equations are solved by the finite volume method in a system of nonorthogonal coordinates which is fitted to the phase-averaged wave surface. The predicted drift current is fairly reasonable and the drag coefficient of sea-surface predicted with the newly developed interface conditions shows good agreement with previous measurements when breaking waves do not exist.
Drift current induced by wind and waves is investigated with phase-averaged Navier-Stokes equation in which the Reynolds stress is closed by k-ε model. The governing equations are solved by the finite volume method in a system of nonorthogonal coordinates which is fitted to the phase-averaged wave surface. The predicted drift current is fairly reasonable and the drag coefficient of sea-surface predicted with the newly developed interface conditions shows good agreement with previous measurements when breaking waves do not exist.
1992, (2): 189-204.
Abstract:
In this paper, a comparison among the seven large meanders of the Kuroshio is made in order to probe into their similarity and differences. The major results are described as follows.
1. Although the three phases for the seven large meanders such as their formations, maturity, as well as decline are very similar to one another, each meander has its own trivial difference in detail.
2.The paths of the first six large meanders in the mature phase may be classified into ten types:U1, V1, U2, V2, U1', V1', U2', V2',φ and W.
3.The seven large meanders may be grouped into two patterns, i. e., pattern Ⅰ and pattern Ⅱ. Pattern Ⅰ includes the first and the fourth large meanders, and pattern Ⅱ includes the rest of the above meanders.
4. Four standards for identifying the large meanders of the Kuroshio are put forward.
In this paper, a comparison among the seven large meanders of the Kuroshio is made in order to probe into their similarity and differences. The major results are described as follows.
1. Although the three phases for the seven large meanders such as their formations, maturity, as well as decline are very similar to one another, each meander has its own trivial difference in detail.
2.The paths of the first six large meanders in the mature phase may be classified into ten types:U1, V1, U2, V2, U1', V1', U2', V2',φ and W.
3.The seven large meanders may be grouped into two patterns, i. e., pattern Ⅰ and pattern Ⅱ. Pattern Ⅰ includes the first and the fourth large meanders, and pattern Ⅱ includes the rest of the above meanders.
4. Four standards for identifying the large meanders of the Kuroshio are put forward.
1992, (2): 205-218.
Abstract:
The long-term time series analysis of the SST (sea surface temperature) in the Eastern Equatorial Pacific Ocean and the monthly MSL (mean sea level) in the tropical Pacific Ocean is conducted. Their quasiperiodic and low-frequency oscillation features are revealed. The significant periods of low-frequency fluctuations for monthly MSL in the area of 20°N-20°S are between 43.5 months and 50.0 months, approximating closely to 47.6 months which is the significant period of SST in the Eastern Equatorial Pacific Ocean. From the results of space-spectral analysis, the low-frequency fluctations of monthly MSL in the tropical Pacific Ocean appear to have a anticlockwise circularly-propagating pattern, which is, the Eastern Pacific Ocean (off-shore of Mexico)→the area of NEC (North Equatorial Current)→the Western Equatorial Pacific Ocean→the area of NECC (North Equatorial Counter-Current)→the Eastern Equatorial Pacific Ocean. The phases of the pattern correspond to those of El Nino cycle. On the basis of the above results,a basic model is established with stepwise-regression method,which can forecast El Nino events by the variations of monthly MSL at a few stations fn the tropical Pacific Ocean 4 months ahead. The correlation inefficient between the forrrnsted series and the nknsrrved one is 0.89.
The long-term time series analysis of the SST (sea surface temperature) in the Eastern Equatorial Pacific Ocean and the monthly MSL (mean sea level) in the tropical Pacific Ocean is conducted. Their quasiperiodic and low-frequency oscillation features are revealed. The significant periods of low-frequency fluctuations for monthly MSL in the area of 20°N-20°S are between 43.5 months and 50.0 months, approximating closely to 47.6 months which is the significant period of SST in the Eastern Equatorial Pacific Ocean. From the results of space-spectral analysis, the low-frequency fluctations of monthly MSL in the tropical Pacific Ocean appear to have a anticlockwise circularly-propagating pattern, which is, the Eastern Pacific Ocean (off-shore of Mexico)→the area of NEC (North Equatorial Current)→the Western Equatorial Pacific Ocean→the area of NECC (North Equatorial Counter-Current)→the Eastern Equatorial Pacific Ocean. The phases of the pattern correspond to those of El Nino cycle. On the basis of the above results,a basic model is established with stepwise-regression method,which can forecast El Nino events by the variations of monthly MSL at a few stations fn the tropical Pacific Ocean 4 months ahead. The correlation inefficient between the forrrnsted series and the nknsrrved one is 0.89.
1992, (2): 219-230.
Abstract:
On the basis of the in situ data of DO2, pH, SiO2, PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.
1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.
2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advection and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.
3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advection process and the upwelling degree of the subsurface Kuroshio water to the shelf.
4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area.
On the basis of the in situ data of DO2, pH, SiO2, PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.
1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.
2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advection and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.
3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advection process and the upwelling degree of the subsurface Kuroshio water to the shelf.
4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area.
1992, (2): 231-235.
Abstract:
Effects of the mixture of β-ecdysone and polypodine-B (2:1 W/W) on the moulting and growth of prawn, Penaeus orientalis were studied in laboratory by rearing the animal with the added compound diets. The results showed that the addition of the moulting hormone (M. H) mixture to compound diets, from 1.33×10-6 to 30×10-6, could increase moulting activity and growth rate of the prawn to different extents, among which the 5. 33×10-6-10.67×10-6 addition had statistically significant effects. However, 60×10-6 added diets caused moulting and growth inhibitions and cuticle thickening. The analyses of protein, water and ash contents of the prawn showed no remarkable differences between hormone dosed animals and the control.
Effects of the mixture of β-ecdysone and polypodine-B (2:1 W/W) on the moulting and growth of prawn, Penaeus orientalis were studied in laboratory by rearing the animal with the added compound diets. The results showed that the addition of the moulting hormone (M. H) mixture to compound diets, from 1.33×10-6 to 30×10-6, could increase moulting activity and growth rate of the prawn to different extents, among which the 5. 33×10-6-10.67×10-6 addition had statistically significant effects. However, 60×10-6 added diets caused moulting and growth inhibitions and cuticle thickening. The analyses of protein, water and ash contents of the prawn showed no remarkable differences between hormone dosed animals and the control.
1992, (2): 237-254.
Abstract:
On the basis of the data of zooplankton biomass and three major taxa——Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:
The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.
On the basis of the data of zooplankton biomass and three major taxa——Copepoda, Chaetognatha andSiphonophora of May-June 1986, July-August and December 1987, the distributional patterns and the indicator species of zooplankton in the Kuroshio and adjacent waters of the East China Sea are preliminarily studied. The results are as follows:
The horizontal distribution of zooplankton biomass and the abundance of copepods, chaetognaths and siphonophores arecurred in the continent area northwest of Taiwan and the south-centre section of the East China Sea continent, which are the mix front of different waters. Zooplankton in the water area inside of Ryukyu Islands presented low abundance and high diversity. There are clear seasonal variations in zooplankton biomass and abundance in the study area. The strength or weakness of different water masses and fronts is the basic reason for the variations of zooplankton biomass and abundance.
1992, (2): 255-273.
Abstract:
Marine chroococcoid phycoerythrin-containing Synechococcus spp. recently have been implicated as a substantial component of the photosynthetic picoplankton in the ocean. Although the importance of Synechococcus as food sources for heterotrophic nanoplankton are now recognized, the information about its cycling of biomass and diel patterns is limited and the methodology used varies according to different authors. A selective metabolic inhibitor method was used to allow simultanous estimation of both growth rates and grazing disappearance rates of Synechococcus. Results obtained in the English Channel show growth rates ranging from 0.25 to 0.72 d-1 with an average value of 0.51 d-1 and grazing disappearance rates ranged from 0.21 to 0.64 d-1 (mean=0.44 d-1). Offshore in the Celtic Sea of the Northeast Atlantic Ocean, both rates were lower than in the channel. The similarity between average growth and grazing rates suggests a rapid recycling of Synechococcus biomass.
Marine chroococcoid phycoerythrin-containing Synechococcus spp. recently have been implicated as a substantial component of the photosynthetic picoplankton in the ocean. Although the importance of Synechococcus as food sources for heterotrophic nanoplankton are now recognized, the information about its cycling of biomass and diel patterns is limited and the methodology used varies according to different authors. A selective metabolic inhibitor method was used to allow simultanous estimation of both growth rates and grazing disappearance rates of Synechococcus. Results obtained in the English Channel show growth rates ranging from 0.25 to 0.72 d-1 with an average value of 0.51 d-1 and grazing disappearance rates ranged from 0.21 to 0.64 d-1 (mean=0.44 d-1). Offshore in the Celtic Sea of the Northeast Atlantic Ocean, both rates were lower than in the channel. The similarity between average growth and grazing rates suggests a rapid recycling of Synechococcus biomass.
1992, (2): 275-286.
Abstract:
The chief purpose of the research was to understand the physiological function change regularity, performance and adaptability of the human body living and working under high pressure for prolonged time.
In January 1989, 4 naval divers entered the habital of NMRI's 500 msw saturation diving system after a series of adaptive diving training. The breathing mixture was helium-oxygen. After 55 h compression (including intermediate stages) the 350 msw depth was reached, where the divers lived and worked for 72 h 10 min. No sign of discomfort or significant HPNS was found in the 4 divers.
The second and third day of the saturation exposure, the divers carried out 370 msw dry and wet chamber excursion diving 2 man-time each, the divers effectively carried out operational work under water, the total excursion time was 1 h each excursion dive.
The chief purpose of the research was to understand the physiological function change regularity, performance and adaptability of the human body living and working under high pressure for prolonged time.
In January 1989, 4 naval divers entered the habital of NMRI's 500 msw saturation diving system after a series of adaptive diving training. The breathing mixture was helium-oxygen. After 55 h compression (including intermediate stages) the 350 msw depth was reached, where the divers lived and worked for 72 h 10 min. No sign of discomfort or significant HPNS was found in the 4 divers.
The second and third day of the saturation exposure, the divers carried out 370 msw dry and wet chamber excursion diving 2 man-time each, the divers effectively carried out operational work under water, the total excursion time was 1 h each excursion dive.
1992, (2): 287-303.
Abstract:
An exact analytic solution for wave diffraction by wedge or corner with arbitrary angle (rπ) and reflection coefficients (R0 and Rr) is presented in this paper. It is expressed in two forms-series and integral representations, corresponding recurrence relation and asymptotic expressions are also derived. The solution is simplified for some special cases of rπ. For Rr=R0,r=1/N and Rr≠R0,r=1/2N, the solution can be reduced to linear superpositions of incident and partially reflected waves, hence a nonlinear solution of forth order for this problem can be obtained by using the author's theory of nonlinear interaction among gravity surface waves. The given solution is related to inhomogeneous Robin boundary conditions, which include the Neumann boundary conditions usually accepted in wave diffraction theory.
An exact analytic solution for wave diffraction by wedge or corner with arbitrary angle (rπ) and reflection coefficients (R0 and Rr) is presented in this paper. It is expressed in two forms-series and integral representations, corresponding recurrence relation and asymptotic expressions are also derived. The solution is simplified for some special cases of rπ. For Rr=R0,r=1/N and Rr≠R0,r=1/2N, the solution can be reduced to linear superpositions of incident and partially reflected waves, hence a nonlinear solution of forth order for this problem can be obtained by using the author's theory of nonlinear interaction among gravity surface waves. The given solution is related to inhomogeneous Robin boundary conditions, which include the Neumann boundary conditions usually accepted in wave diffraction theory.
1992, (2): 305-316.
Abstract:
