A two-cell circulation associated with a front observed in coastal upwelling regions is studied numerically in a three-dimensional level model. An ocean with a flat bottom is forced by the wind stress with a longshore variation. Upwelling is induced in the region next to the coast. In association with the upwelling, the pycnocline slopes up toward the coast and intersects the sea surface forming a front. After that, downwelling is induced just inshore-side of the front and upwelling offshore-side. The transverse circulation in the present model seems to reproduce the observed two-cell circulation. It is found that the generation of the two-cell circulation is due to deviations of the longshore flow from the thermal-wind relation(geostrophy). The deviations are caused by the onshore-offshore movements of the front. Although no vorticity input through the wind stress is assumed, several barotropic vortices are induced by the effect of the inclination of the pycnocline and grow as long as the winds continue to blow. The observed poleward undercurrent may be interpreted as a combination of motions of the internal mode associated with the front and a barotropic flow associated with a cyclonic vortex.

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Light scattering profiles and water samples for filtration of suspended particulate matter were obtained during fall, 1973, from Ice Island T-3, then located about 50 miles north of Ellesmere Island. The profiles reveal almost no variability in scattering, either in the water column, or in time during our two weeks of field work. Gravimetric analysis of the filtered suspended particulate matter shows that mass concentrations are low, averaging about 7 μg 1^-1, and that they too remain very constant. The four water masses present in the Arctic Ocean could not be distinguished by our observations of light scattering and mass concentration of suspended particulates.

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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 by H=BT^3/2 and σ=2 π BT^-1/2, respectively, are very well supported by the data, where H(=gH/u²) and T(=gT/u) are the dimensionless significant wave height and period, respectively, σ the wave steepness, u the friction velocity of air, g the acceleration of gravity, and B=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 ∅(σ) =α_sguσ^-4, where σ is the angular frequency and ∅(σ) the spectral density. The value of α_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 con taining well-defined higher harmonics of the spectral peak, and consequently there is an apparent difference in the values of α_s also. However, it is shown that the discrepancy of α_s may be eliminated by evaluating properly the energy level of the spectral form containing higher harmonics.

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A storm moves with a constant speed parallel to a stationary geostrophic current which flows only in the upper layer of a two-layer, infinite ocean. It is assumed that the lower layer is motionless. The quasi-geostrophic approximation is valid for a moving speed less than 4 m s^-1 for a storm radius of 100 km. The primary change of the upper layer thickness is caused by the wind stress divergence and the time integral of the wind stress curl. A cyclonic storm generates upwelling in its wake. The effect of the stationary flow similar to a western boundary current is minor by an order of magnitude and noticeable only on the left edge of the flow. Scaling of equations of motion and continuity for a more general upper geostrophic flow leads to expansion with a parameter α²=gεHm.(fL) ^-2, where gε is reduced gravity, H_m is the maximum thickness of the upper layer, f is Coriolis' parameter and L is the storm radius. The zeroth order perturbations of transport and thickness do not include the stationary flow which appears only in the first order perturbations in α². When there is a coast, the change of the interface near the coast is dependent on the time integral of the wind stress component parallel to the coast, thus leading to upwelling or downwelling according to the center being to the left or right of the coastline.

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This paper gives the results of determination of cadmium, lead and copper in interstitial water of the coastal sediment, Seto Inland Sea, Japan by using anodic stripping voltammetry.
An aliquot of 4-5 ml interstitial water separated from 30-70 ml of sediment is used for the simultaneous determination of ionic cadmium, lead and copper. No significant differences were observed on the content of trace metals between surface water and interstitial water of the top of the sediment.

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The approximate relation of the coefficient of shear diffusion against time is shown by means of a two-level model.

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