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1.
Calcium-alkalinity relationship in the North Pacific   总被引：3，自引：0，他引：3  
The dissolution of calcium carbonate in deep ocean water causes variation in calcium concentration (Ca) and alkalinity (TA) in the ratio of one to two. The decomposition of organic matter generates nitric acid, phosphoric acid and sulfuric acid. A proton flux which is derived from this process also changes alkalinity. Using the variation in nitrate concentration (NO3) as an index of the proton flux, the relationship betweenCa,TA andNO3 is expressed asCa=0.5TA+0.63NO3 The values of Ca obtained from direct measurements in the North Pacific are in good agreement with the values estimated from this equation.  相似文献   

2.
Regeneration of silicate in the Japan Sea, an example of semi-closed sea, was studied. In the Japan Sea Proper Water the apparent regenerative ratio of the nutrients was determined to be:O C N P Si=–289 (116)14.3181.It was assumed that the dissolved silicate present in sea water is grouped into three fractions; 1)preformed silicate of conservative nature, 2)oxidative silicate which dissolves in oxidation process of organisms with consumption of oxygen, and 3)non-oxidative silicate which dissolves without oxygen consumption. The dissolution rate ofnon-oxidative silicate in the Japan Sea Proper Water was estimated to be 0.07g-at. Si/l/yr from the data ofAOU values and assumed rates of oxygen consumption. This dissolution rate ofnon-oxidative silicate agreed with that obtained in the deep Pacific by the vertical advection diffusion model byKido andNishimura (1972).  相似文献   

3.
Using climatological atlas data and historical hydrographic data, the relationship between dynamic height anomaly D and acoustic round-trip travel time in the Pacific Ocean is investigated. A tight, linear relation is found in a region centered on the Kuroshio and Kuroshio Extension. In this region, the slopem of the relation is approximately –50 dyn m s–1, about equal to the value expected for first-baroclinicmode response and twice as large as the value form in the Gulf Stream region of the Atlantic Ocean. The value ofm in the Pacific generally increases in magnitude towards the south and with increasing depth to which the integrals for D and are carried. It is changed only slightly by correcting for the temperature and salinity march of the seasons in the surface layer. The Kuroshio region is established as one in which the record of from an inverted echo sounder can be interpreted reliably in terms of D. An inverted echo sounder can also be used in this way in a number of other regions of the Pacific, although the available hydrographic data sets are too sparse to establish their boundaries clearly.  相似文献   

4.
The downward short- and long-wave radiation fluxes at the sea surface (S, L) were measured aboard the R/VHakuho Maru, University of Tokyo, for the period of 117 days on six cruises from 1981 to 1985 in the western North Pacific near Japan. The upward fluxes of short- and long-wave radiation (S, L) were calculated by Payne's (1972) table and the Stefan-Boltzmann's law, respectively. The sensible and laten heat fluxes (Q h ,Q e ) were also estimated from an aerodynamic bulk method.From April to August, the daily mean value ofS varied with the amplitude of 100200 Wm–2. The value ofS was estimated approximately 6% ofS in all seasons. The difference betweenL andL was so small that the net radiation flux (Q n ) was dominated byS. In addition, the net heat flux at the sea surface was also dominated byS due to small values ofQ h andQ e , and then the ocean was warmed at the rate of 111 Wm–2 in April and 63 Wm–2 in August in the Oyashio Area, and 132 Wm–2 in May and 164 Wm–2 in June in the Kuroshio Area, respectively.From September to March, a remarkable negative correlation between the day to day variation ofS and that ofL was observed except when an intense cold air outbreak occurred. It was found that the correlation was caused by the cloud climatological feature of the western North Pacific in this period.S was not a dominant factor in the net heat flux. The value ofQ h +Q e in the Kuroshio Area ranged from 260 Wm–2 to 630 Wm–2, much larger thanQ n which ranged from –8 Wm–2 to 92 Wm–2 in the leg mean values (each leg period was about 10 days). Then the ocean was cooled at the rate of –160–620 Wm–2 during this period. The net heat flux in the Kuroshio Area averaged over five legs from late November to February was –473 Wm–2. This value is 50100% larger than the climatological values reported so far.The temporal and spatial variability of radiation fluxes and heat fluxes during each leg was also discussed.  相似文献   

5.
The chemical states of iron in near-shore and deep-sea sediments were investigated by means of57Fe Mössbauer spectroscopy in combination with selective and nonselective chemical leachings. As far as a limited number of the sediments analyzed are concerned, Mössbauer spectra of near-shore sediments consist of high-spin paramgnetic ferrous (=1.13 mm/s, Eq=2.65 mm/s) and paramagnetic ferric (=0.35 mm/s, Eq=0.64 mm/s) components, while those of deep-sea sediments are composed of high-spin paramagnetic ferrous, paramagnetic ferrous, paramagnetic ferric and magnetic ferric (0.4 mm/s,H510 KG) components. The Fe2+/Fe3+ ratios of deepsea sediments are much smaller than those in near-shore sediments, while the total contents of iron in the former are much higher than those in the latter. This is principally due to the high contents of authigenic ferric oxides in deep-sea sediments. Further, in the aluminosilicate fraction, the Fe2+/Fe3+ ratios of deep-sea sediments are also smaller than those of near-shore sediments. This is probably attributed to high contents of clay minerals and authigenic aluminosilicates in deep-sea sediments relative to near-shore ones. The magnetic components in deepsea sediments are attributable to hematite, magnetite and/or maghemite.  相似文献   

6.
Observational data on air-sea boundary processes at the Shirahama Oceanographic Tower Station, Kyoto University, obtained in November, 1969, was analyzed and presented as an example representing the structure of growing wind-wave field. The condition was an ideal onshore wind, and the data contained continuous records of the wind speed at four heights, the wind direction, the air and water temperatures, the tides, and the growing wind waves, for more than six hours. The main results are as follows. Firstly, in both of the wind speed and the sea surface wind stress, rather conspicuous variations of about six-minute period were appreciable. Secondly, the three-seconds power law and its lemma expressed byH *=BT *3/2 and=2BT *–1/2, respectively, are very well supported by the data, whereH *(gH/u * 2) andT *(gT/u *) are the dimensionless significant wave height and period, respectively, the wave steepness,u * the friction velocity of air,g the acceleration of gravity, andB=0.062 is a universal constant. Thirdly, the spectral form for the high-frequency side of the spectral maximum is well expressed by the form of()= sgu*–4, where is the angular frequency and() the spectral density. The value of s is determined as 0.062±0.010 from the observational data. There is a conspicuous discrepancy between the spectral shape of wind waves obtained in wind-wave tunnels and those in the sea, the former containing well-defined higher harmonics of the spectral peak, and consequently there is an apparent difference in the values of s also. However, it is shown that the discrepancy of s may be eliminated by evaluating properly the energy level of the spectral form containing higher harmonics.  相似文献   

7.
Values of root mean square slope 0 and its variations -0 are estimated using the brightness field of an image of the surface of the sea near a speck of light. When 0 and -0 are defined it is highly important to take into account direct as well as dissipated solar radiation.The space-time analysis of the structure of the image brightness field is performed. This gives an opportunity to estimate dispersion relationship and the running effect of a brightness contrast packet. Comparison of the parameters obtained with the theoretical dispersion ratio of internal waves (IW) allows one to make a conclusion that IW surface manifestations are recorded in a frame.UDK 551.463.5  相似文献   

8.
Bispectral analysis is applied to records of the vertical profile of the vertical temperature gradient in the oceanic thermocline in the San Diego Trough. The bispectra exhibit three notable features; (1) bispectral peaks at the points (0.2 m–1, 0.2 m–1) and (0.2 m–1, 0.1 m–1), (2) bispectral ridges along the lines ( 1= 0, 2= 0 and 1+ 2= 0 corresponding to peak wavenumbers 0 in power spectra, and (3) array of bispectral peaks of interval of 0.2 m–1 The results are compared with the bispectra of several modeled time series of spike-array type. The periodicity of 5 m found in the records seems to have two meanings: spacing of predominant spikes and wavelength of predominant sinusoidal wave. If this indicates the existence of internal waves having a vertical wavelength the same as the scale of homogeneous layers, it would suggest the possible importance of internal waves in the formation and maintenance mechanisms of oceanic microstructure.  相似文献   

9.
Dependences have been determined which connect the parameters of the dispersion relation of the lowest mode of internal waves with the integral characteristics of the seasonal thermocline when 10 min30 min, 20 mh150 m, and 0·4 m2/s2 Q5·2 m2/s2.Translated by Mikhail M. Trufanov.  相似文献   

10.
Local balance in the air-sea boundary processes   总被引：2，自引：0，他引：2  
A combination of the three-second power law, presented in part I for wind waves of simple spectrum, and the similarity of the spectral form of wind waves, leads to a new concept on the energy spectrum of wind waves. It is well substantiated by data from a wind-wave tunnel experiment.In the gravity wave range, the gross form of the high frequency side of the spectrum is proportional tog u * –4, whereg represents the acceleration of gravity,u * the friction velocity, the angular frequency, and the factor of proportionality is 2.0×l0–2. The wind waves grow in such a way that the spectrum slides up, keeping its similar form, along the line of the gross form, on the logarithmic diagram of the spectral density,, versus. Also, the terminal value of, at the peak frequency of the fully developed sea, is along a line of the gradient ofg 2 –5.The fine structure of the spectrum from the wind-wave tunnel experiment shows a characteristic form oscillating around the –4-line. The excess of the energy density concentrates around the peak frequency and the second- and the third-order harmonics, and the deficit occurs in the middle of these frequencies. This form of the fine structure is always similar in the gravity wave range, in purely controlled conditions such as in a wind-wave tunnel. Moving averages of these spectra tend very close to the form proportional to –5.As the wave number becomes large, the effect of surface tension is incorporated, and the –4-line in the gravity wave range gradually continues to a –8/3-line in the capillary wave range, in accordance with the wind-wave tunnel data. Likewise, the –5-line gradually continues to a –7/3-line.Also, through a discussion on these results, is suggested the existence of a kind of general similarity in the structure of wind wave field.  相似文献   

11.
Various wind velocitiesu *,U /2,U andU 10 are correlated to the measured growth rate of water waves , whereu * is the friction velocity of the wind, andU /2,U andU 10 are the wind speeds respectively at the heights /2, and 10m above sea surface (: wave length). It is shown that within a range of the dimensionless wind speed, 0.1<u * /C<0.6, there are no appreciable differences in the correlations, whereC is the phase velocity of water waves. The present relation between andU shows qualitatively similar properties as the one obtained by Al'Zanaidi and Hui (1984); the growth rate for waves with rough surface is larger than that with smooth surface. However, our present relations give, for the both waves with different surface roughness, larger values by factors 1.71.8 than those given by Al'Zanaidi and Hui's relation.  相似文献   

12.
The amount of penetration of a western boundary current into a marginal sea which is connected to an open ocean by two narrow straits is estimated from a linear, steady and barotropic theoretical model. In this model the western boundary current in the open ocean is driven by a wind stress imposed at the sea surface. The inflow of the water of the open ocean into the marginal sea is caused by the pressure difference between two straits produced by the wind-driven circulation in the open ocean.Main external parameters are combined into two non-dimensional parameters; and (the ratio of the depth of the marginal sea to that of the open ocean), whereb is the distance between north and south boundaries of the ocean,D 0 is the depth of the open ocean, is the latitudinal variation of the Coriolis parameter andR is the coefficient of friction. The friction is assumed to be proportional to the flow velocity.In the limit of infinite the volume transport into the marginal sea is not affected by the width of two straits and . It is mainly controlled by the wind stress and the positions of two straits. For finite values of , however, the volume transport depends considerably on and the width of the straits.Guided by both this model and physical considerations, we obtained a relation between the volume transport into the marginal sea and the external parameters. This relation predicts that about 2 % of the volume transport of the Kuroshio penetrates into the Japan Sea.  相似文献   

13.
A coupled model of air-wave-sea interaction is modified based on a new roughness formulation and the latest data. The model parameters for aerodynamic roughness from below (ARB) and wave-dependent roughness from above (ARA, z 0a ) are assumed equal. The combined roughness is assumed to be a function of friction velocity, gravity, air and seawater densities, and wave age (c w ). The model is used in a study of wave-enhanced turbulence under breaking waves to predict turbulent dissipation (), ARA, and drag coefficient (C d ). Both waves and shear production are considered as sources of ocean turbulent energy. The atmospheric part of the model is used only to specify a correct condition at the interface. Numerical experiments are performed to study the -distribution, z 0a and C d , and to compare with data. The major achievement is model verification using all available data. The first full application of this model is in conjunction with an ocean circulation model in a coupled circulation-wave system. Simulations show that the -distribution is strongly dependent on local wind-forced wave heights. For each wind and wave state there is a particular wave-dependent depth that is verified by data. The comparison shows that the model predicted agrees well with the observed of the z –4 law distribution of Gargett (1989). Simulations also show that waves have an important role in causing to differ from the classical wall-layer theory and z 0a , with a value of 0.30 for the empirical constant a a . The model-predicted , z 0a , C d and C gd agree well with data.  相似文献   

14.
Microbial Diversity in Nankai Trough Sediments at a Depth of 3,843 m   总被引：6，自引：0，他引：6  
Dense populations of bivalves, primarily Calyptogena sp., were observed at cold seeps of the Nankai Trough. Bacterial input to the sediment was estimated through determination of phospholipid ester-linked fatty acid (PLFA) and DNA profiles. Results indicated a bacterial biomass of 109 cells (g dry wt)-1 while individual fatty acid profiles revealed a predominance of monounsaturated fatty acids, mainly 18:1 isomers. The presence of these fatty acids can be interpreted to reflect a response to low temperature and a predominance of psychrophilic bacteria. DNA fragments encoding bacterial ribosomal RNA small-subunit sequences (16S rDNA) were amplified by the polymerase chain reaction method using DNA extracted directly from the sediment samples. From the sequencing results, at least 19 kinds of bacterial 16S rDNAs related to mostly the Proteobacteria and a few gram-positive bacteria were identified. These results suggest that the bacterial community in the Nankai Trough sediments consists of mainly bacteria belonging to the Proteobacteria , , and subdivisions. Bacteria belonging to the and subdivisions, which are known to include epibiont and sulfate reducing bacteria, respectively, were mostly detected in the sediment obtained from inside the area of the Calyptogena community, and the -Proteobacteria may function to supply reduced sulfur to bacterial endosymbionts of Calyptogena.  相似文献   

15.
The general statement of a non-linear problem in modelling a barotropic tide for the limited part of a real shelf and the problems related to artificial division of the computation area in the ocean by a liquid boundary are considered. Linear combinations of various types of boundary conditions and analytical expressions are used to describe the tidal wave structure at the liquid boundaries. The results of test computations for basins with the simplest outlines are given. The model is used to reconstruct the spatial distribution of characteristics of theM 2 tide on the shelf of Guinea. The methods of computation and specification of unambiguously determined model parameters are described. Joint analysis of the modelling results and the field data has been carried out. The tidal map of theM 2 wave is plotted for the area under investigation.Translated by Mikhail M. Trufanov.  相似文献   

16.
We compare the results obtained by using theoretical and semiempirical models developed for the evaluation of the dissipation rate of turbulent energy in a stratified ocean with independent distribution of this quantity established by the authors for the active layer of the Black Sea (50–300 m) by using a one-dimensional model taking into account the balance of heat, salt, and fluid inside the layer. It is shown that, in a layer with gradual variation of the Väisälä–Brunt frequency N as a function of depth, the predominant sink of the energy of motion into dissipation N 2 is ensured by the flow of energy through the spectrum of internal waves toward low frequencies and small vertical scales. On the contrary, in layers with abrupt drops of density as a function of depth (layers with jumps of density), an important role is played by the interface-type waves and the dependence of on N transforms into N .  相似文献   

17.
The bacterial populations of mangrove swamps of Killai backwaters (11°21–11°29N, 79°46–79°50E, South India) were studied during August 1968 (Pre monsoon period) and December (post monsoon period). The presence of these groups such as agar digesters, algin digesters, cellulose digesters, sulphate reducers etc., bring about transformation of organic matter in the mangrove swamps. The presence of denitrifiers in mangrove swamps and in association with the molluscs may bring about the precipitation of calcium carbonate by removing the acid radicals such as sulphate and nitrite, increasing alkalinity. The luminiscent bacteria such asVibrio andAeromonas were also isolated in mangrove swamps of Killai backwaters. The iron bacteria likeLeptothrix sp. andGallionella sp. were also isolated from mangrove swamps of Killai backwaters.  相似文献   

18.
The maximum uptake rate (max) and affinity constant (K s) for nitrate and ammonium were estimated in the surface water of offshore Oyashio in May (spring) and September (summer), 1990. The average max/Chl.a for ammonium was 2.1 times larger than that of nitrate in both seasons. The average max/Chl.a for both nitrogens were 3.5 times larger in summer than in spring. Water temperature and size composition of phytoplankton population were related to the seasonal difference in the max/Chl.a. Phytoplankton population showed high affinity for both nitrogens in the spring and summer. In addition, the contribution of new production to total production was estimated by max[max–No3/(max–NO3+max–NH4)]. The spring value was in the range of 0.26 to 0.45 (mean±SD=0.35±0.092), and the values in spring bloom were especially a little over 0.4. The summer value was in the range of 0.30 to 0.37 (0.34±0.04).  相似文献   

19.
Spectral characteristics of rapid-changing random data in the ocean are discussed. Analysis shows that, if records are approximated by saw-toothed random series 1 and step series 2, 1 and 2 generally have spectral ranges of the –4th power and –2nd power, respectively, with respect to frequency (or wave number).  相似文献   

20.
Themisto japonica was reared at 1, 5, 8, and 12°C in the laboratory to estimate its intermoult period (IP) and increase in body length (BL) at each moulting (BL).IP was found to be a function of temperature andBL of the specimens, longerIPs being associated with lower temperature and larger specimens.BL was not affected by temperature but increased with growth of the specimens. Observations on consecutive moults indicated that one new segment was added to pleopod rami at each moulting.BLs obtained from the measurement of the segment number of pleopod rami andBL of wild specimens were slightly larger than values obtained from laboratory-raised specimens.IP data obtained from laboratory-reared specimens are combined withBL data from wild specimens to establish a growth model forT. japonica from its release from the marsupium (1.31 mmBL) to the maximum size (17 mmBL) as a function of temperature. This growth model predicts that a total of of 18 moultings is needed forT. japonica to reach the maximum size regardless of temperature, although the time needed to reach the maximum size is highly dependent on temperature. The life cycle, from the newly released larvae (1.31 mmBL) to the spent females (10–17 mmBL), was estimated as 333–593 days at 1°C, 195–347 days at 5°C, 118–210 days at 10°C and 82–146 days at 15°C; the last may be the upper temperature limit forT. japonica. Growth rates ofT. japonica expressed on the basis of body mass are comparable to the rates of euphausiids of equivalent size when the effect of temperature is accounted for. Feeding conditions ofT. japonica in the field are also discussed.  相似文献   

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