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The tides and tidal currents in the Jiaozhou Bay
OLR t 1987) 34 (9)
A Ph3sical Oceanography
87:4903 Narimousa, S. and T. Maxworthy, 1986. Effects of a discontinuous surface stress on a model of coastal upweiling. J. phys. Oceanogr., 16(12):2071-2083. We report on laboratory model experiments in which coastal upwelling was created by a radially discontinuous surface stress in the presence of bottom topography in the form of a ridge. An anticyclonic torque was thus applied to the surface of the fluid at the location of the stress discontinuity, which in turn generated large offshore cyclonic and anticyclonic eddies in the stress-free region. When the upwelled front interacted with this offshore eddy field, dense, upwelled water was transported far offshore as jetlike flows. The strong interaction between the stress discontinuity 'front' and the upwelled front at the ridge resulted in an upwelling maximum and a downstream jet at the ridge that were weaker than those reported previously. A large number of flow-marking particles accumulated in the region where the ridge intersected the stress discontinuity. Dept. of Mechanical Engng, Univ. of Southern Calif., Los Angeles, CA 90089, USA.
AI50. Tides and sea level 87:4904 Ding, Wenlan, 1986. The tides and tidal currents in the Jiaozhou Bay. Stud. mar. sin., 26:1-25. (In Chinese, English abstract.) Inst. of Oceanol., Acad. Sinica, People's Republic of China.
87:4905 Mayer, D.A. and J.C. Larsen, 1986. Tidal transport in the Florida Current and its relationship to tidal heights and cable voltages. J. phys. Oceanogr., 16( 12):2199-2202. A linear relationship between tidal height and tidal transport in the Straits of Florida is confirmed. Transport estimates from this relationship for the O~ and M 2 constituents are compared with those computed from cable voltages across the Florida Current. These estimates are independent in that the weighted tidal height model was developed using collective sets of current meter and velocity profiler data obtained at different times of the year and in different locations. The cable voltages, however, were calibrated using a quasi-synoptic integration of depth-averaged profiler data. N O A A / A O M L , Miami, FL 33149, USA.
735
A160. Waves, oscillations 87:4906 Artale, V., E. Salusti and R ~. Santoleri, 1986. Lyapunov stability of solitary rotational water waves. Geophys. astrophys. Fluid Dynam., 37(3): 237-251. Generalizing an idea of Arnold, we discuss the hydrodynamic stability ~ la Lyapunov of solitary water-waves which are rotational solutions of the Euler equation, travelling with constant phase speed. The system is stable for (a) small vertical or horizontal space scale perturbations; (b) perturbations with a very long vertical space scale and very small horizontal space scale or with a very long horizontal space scale and very small vertical space scale. The system is also stable for irrotational perturbations. ENEA-CREA, S. Teresa, P.O. Box 316, la Spezia, Italy. 87:4907 Gerber, Marius, 1987. The Benjamin-Feir instability of a deep-water Stokes wavepacket in the presence of a non-uniform medium. J. Fluid Mech., 176:311-332.
The influence of a non-uniform medium on the Benjamin-Feir instability of weakly nonlinear deepwater waves has been approached via a suitable nonlinear Schrodinger equation. An applicable dispersion relation and energy equation was derived by the averaged Lagrangian technique. With the assumption that the lengthscale of current variation is much greater than the lengthscale of the wavepacket, a cubic SchrOdinger equation with slowly varying coefficients is obtained. Different examples of non-uniform media are treated: (1) waves on a current with variation along the stream; (2) waves on a shear current; and (3) long deep-water gravity waves interacting with shorter waves. Dept. of Ocean Engng, Stellenbosch Univ., Stellenbosch 7600, South Africa. 87:4908 Johnson, E.R., 1987. Topographic waves in elliptical basins. Geophys. astrophys. Fluid Dynam., 37(4): 279-295. Simple analytical solutions are presented for topographic waves in elliptical basins whose isobaths form a set of confocal ellipses, and it is shown that the previous solution presented for this problem is incomplete. The complete solutions no longer agree so closely with observations in Swiss lakes and the Great Lakes. The class of profiles considered is extended to include flat-bottomed basins, allowing a more realistic estimate of the velocity distribution in such basins and suggesting a slightly closer agree-
A Ph3sical Oceanography
87:4903 Narimousa, S. and T. Maxworthy, 1986. Effects of a discontinuous surface stress on a model of coastal upweiling. J. phys. Oceanogr., 16(12):2071-2083. We report on laboratory model experiments in which coastal upwelling was created by a radially discontinuous surface stress in the presence of bottom topography in the form of a ridge. An anticyclonic torque was thus applied to the surface of the fluid at the location of the stress discontinuity, which in turn generated large offshore cyclonic and anticyclonic eddies in the stress-free region. When the upwelled front interacted with this offshore eddy field, dense, upwelled water was transported far offshore as jetlike flows. The strong interaction between the stress discontinuity 'front' and the upwelled front at the ridge resulted in an upwelling maximum and a downstream jet at the ridge that were weaker than those reported previously. A large number of flow-marking particles accumulated in the region where the ridge intersected the stress discontinuity. Dept. of Mechanical Engng, Univ. of Southern Calif., Los Angeles, CA 90089, USA.
AI50. Tides and sea level 87:4904 Ding, Wenlan, 1986. The tides and tidal currents in the Jiaozhou Bay. Stud. mar. sin., 26:1-25. (In Chinese, English abstract.) Inst. of Oceanol., Acad. Sinica, People's Republic of China.
87:4905 Mayer, D.A. and J.C. Larsen, 1986. Tidal transport in the Florida Current and its relationship to tidal heights and cable voltages. J. phys. Oceanogr., 16( 12):2199-2202. A linear relationship between tidal height and tidal transport in the Straits of Florida is confirmed. Transport estimates from this relationship for the O~ and M 2 constituents are compared with those computed from cable voltages across the Florida Current. These estimates are independent in that the weighted tidal height model was developed using collective sets of current meter and velocity profiler data obtained at different times of the year and in different locations. The cable voltages, however, were calibrated using a quasi-synoptic integration of depth-averaged profiler data. N O A A / A O M L , Miami, FL 33149, USA.
735
A160. Waves, oscillations 87:4906 Artale, V., E. Salusti and R ~. Santoleri, 1986. Lyapunov stability of solitary rotational water waves. Geophys. astrophys. Fluid Dynam., 37(3): 237-251. Generalizing an idea of Arnold, we discuss the hydrodynamic stability ~ la Lyapunov of solitary water-waves which are rotational solutions of the Euler equation, travelling with constant phase speed. The system is stable for (a) small vertical or horizontal space scale perturbations; (b) perturbations with a very long vertical space scale and very small horizontal space scale or with a very long horizontal space scale and very small vertical space scale. The system is also stable for irrotational perturbations. ENEA-CREA, S. Teresa, P.O. Box 316, la Spezia, Italy. 87:4907 Gerber, Marius, 1987. The Benjamin-Feir instability of a deep-water Stokes wavepacket in the presence of a non-uniform medium. J. Fluid Mech., 176:311-332.
The influence of a non-uniform medium on the Benjamin-Feir instability of weakly nonlinear deepwater waves has been approached via a suitable nonlinear Schrodinger equation. An applicable dispersion relation and energy equation was derived by the averaged Lagrangian technique. With the assumption that the lengthscale of current variation is much greater than the lengthscale of the wavepacket, a cubic SchrOdinger equation with slowly varying coefficients is obtained. Different examples of non-uniform media are treated: (1) waves on a current with variation along the stream; (2) waves on a shear current; and (3) long deep-water gravity waves interacting with shorter waves. Dept. of Ocean Engng, Stellenbosch Univ., Stellenbosch 7600, South Africa. 87:4908 Johnson, E.R., 1987. Topographic waves in elliptical basins. Geophys. astrophys. Fluid Dynam., 37(4): 279-295. Simple analytical solutions are presented for topographic waves in elliptical basins whose isobaths form a set of confocal ellipses, and it is shown that the previous solution presented for this problem is incomplete. The complete solutions no longer agree so closely with observations in Swiss lakes and the Great Lakes. The class of profiles considered is extended to include flat-bottomed basins, allowing a more realistic estimate of the velocity distribution in such basins and suggesting a slightly closer agree-