764 A. Physical Oceanography OLR(1979)26(12)

Mediterranean outflow. 11. The deep circulation in the vicinity of the Gulf of Cadiz. Deep-Sea Res., 26(5A): 555-568.

An analysis of the field of mass produced a reasonably coherent circulation pattern. Estimates of the velocity of the undercurrent both before and after its subdivision into separate upper and lower cores were in good agreement with several previous direct current meter measurements. Meanders induced by bottom topography are regarded as the main cause of variability in the thermohaline and dynamic properties of the current system. A downstream increase in the volume of transport and the presence of a deep countercurrent at about 1500 m beneath the main outflow are discussed. Laboratorio de Fisica. Instituto Geofisico lnfante D. Luis, Faculdade de Ciencias, Universidade de Lisboa, Rue da Escola Polit~cnica, 58, Lisboa, Portugal.

79:5887 Broecker, W. S., 1979. A revised estimate for the

radiocarbon age of North Atlantic Deep Water. J. geophys. Res., 84(C6): 3218-3226.

Recent data indicate that previous estimation of the average age of North Atlantic Deep Water has been too high and that the extent to which mixing ot" Antarctic Bottom Water influences the t4C/C ratio has been underestimated. Application of this information to previous calculations results in a ventilation time for the deep western Atlantic of about 100 years. Lamont-Dohertv Geological Observatory and Department of Geological Sciences of Columbia University, Palisades, N.Y. 10964, U.S.A. (bwt)

79:5888 Sugimoto, Takashige and Masazumi Taniya, 1978.

Effects of boundary geometries on the intrusion of salt-wedge, i. Numerical experiments and field observations. Sci. Repts Tbhoku Univ., (5, Geo- phys.)25(3): 197-208.

The effects of the narrowness of the mouth and the bottom topography of an estuary are emphasized. Numerical computations involve a two-layer model of an arrested salt-wedge and are compared with field observations. Geophysical Institute, Faculty of Science, T6hoku University, Sendal 980, Japan.

10. Optical properties of sea water {color, transparency, inanimate sus- pended matter, fluorescence, etc.)

79:5889 Kozlyaninov, M. V., 1979. On the radiance index of

seawater. (In Russian: English abstract.) Okean- ologiia, 19(2): 221-227.

The spectral radiance index of light upwelling from below the sea surface is shown to characterize its energy distribution or color. The index is found to be dependent only upon primary hydro-optical properties: correlations among the index, the reflectance function, the absorption coefficient and the vertical attenuation coefficient are presented. (rio)

79:5890 Pelevin, V. N., A. M. Gurfink and Yu. A. Goldin,

1979. Influence of the scattering indicatrix form on the nonstationary light field in the sea. (In Rus- sian.) Okeanologiia, 19(2): 228-232.

Influence of the hydro-optical scattering indicatrix on the form of the impulse transfer functions (Green's functions) for a source-receiver system is investigated. Size of a short light impulse moving into greater depths is qualitatively estimated. (rio)

12. Tides and sea level

79:5891 Chabert D'Hieres, G. and C. Le Provost, 1978. Atlas

des composantes harmoniques de la maree dans la Manche. [Atlas of the harmonic constituents of the tides in the English Channel.] Annls hydrogr.. (5)6(3)(750): %36.

The atlas presents 26 groups of charts giving the distribution of amplitudes and phases of the principal harmonic constituents of the tides throughout the English Channel: net values have been established from observed data with the help of an hydraulic reduced model built upon a rotating platform.

79:5892 Gotlib, V. Yu. and B. A. Kagan, 1979. On parameteri-

zation of the shelf effects in modeling the ocean tides. (In Russian.) Fiz. Atmo~f. Okeana. 15(4): 425-435.

Local and integral methods of parameterizing shell" effects are used to model Patagonian shelf (South Atlantic) deep water tides. Both methods produce highly accurate determinations of the characteristics of the semi-diurnal tide with the exception of quarter- wave resonance which yields only qualitative agreement between solutions. (izs)

79:5893 Heath, R. A., 1979. Resonant over-tide across and

along Tasman Bay, New Zealand. Estuar. coast. mar. Sci.. 8(6): 583-595.

Geographic and bathymetric characteristics of the study area cause non-linear field acceleration of the semi-diurnal tidal motion near D'Urville Island; this

OLR(1979)26(12) A. Physical Oceanography 765

results in strong quarter, sixth and eighth diurnal tidal oscillations. New Zealand Oceanographic Institute, Department of Scientific and Industrial Research, Wellington, New Zealand. (rio)

79:5894 Noble, Marlene and Brad Butman, 1979. Low-

frequency wind-induced sea level oscillations along the east coast of North America. J. geo- phys. Res., 84(C6): 3227-3236.

The spatial and temporal scales of low-frequency wind stress and sea level oscillations between North Carolina and Nova Scotia during the winter are investigated. Correlations among the asymmetry in longshore current amplitude, sign of the wind stress and sea level data are evaluated. Effects of regional, temporal and spatial sea level variations on coastal circulation patterns are considered. U.S. Geological Survey, Woods Hole, Mass. 02543, U.S.A. (rio)

79:5895 Paschini, E. and E. Salusti, 1979. On the Green's

function of Laplace's tidal equation, an applica- tion to the northern Adriatic Sea. Tellus, 31(2): 145-149.

Sea level variations in the Adriatic Sea are obtained as the integral of external forces using the Green's function and known sea level data. Successful predictions of sea level variations at Venice are then derived. Istituto di Fisica "G. Marconi", Universita di Roma, Piazzale delle Scienze, 5, Italy. (rio)

13. Ice

79:5896 Tsurikov, V. L., 1979. The formation and composition

of the gas content of sea ice. J. Glaciol., 22(86): 67-8 I.

Mechanisms of gas porosity formation in sea ice are identified and evaluated for relative importance. Available sea ice gas content data are reviewed and slight deviations from air composition are discussed. For low salinity conditions, gas inclusions may be more important than brine contents in determining sea ice strength. Okeanograficheskaya Komissiya Akademii Nauk S.S.S.R., ul. Vavilova 44, Moskva U.S.S.R. (rio)

14. Waves and oscillations

79:5897 Benjamin, T. B. and J. C. Scott, 1979. Gravity-capil-

lary waves with edge constraints. J. Fluid Mech.. 92(2): 241-267.

Water-wave motions in narrow open channels, wherein the special condition of fixed lines of contact are met, are investigated theoretically and experimentally. A linearized theory involving an unusual eigenvalue problem is presented and tested with analytical methods. Experiments are performed in 'brimful' rectangular channels; theoretical and experimental results are in agreement and point up the unique effects of edge constraints. Mathematical Institute, Oxford OX! 3LB, England. (rio)

79:5898 Craik, A. D. D. and J. A. Adam, 1979.'Explosive'

resonant wave interactions in a three-layer fluid flow.J. Fluid Mech., 92(1): 15-33.

The negative wave energy concept developed for the case of plasmas by Cairns (1979) is shown to be applicable to parallel fluid flow instabilities. Three- wave resonances are analyzed with step-wise velocity and density profiles, and an 'explosive instability,' involving simultaneous growth of all three waves while total energy is conserved, is discovered. This new nonlinear instability may be a powerful mechanism of internal wave generation in the ocean and the atmosphere. Department of Applied Mathematics, University of St. Andrews, Fife, Scotland. (rio)

79:5899 Fujinawa, Yukio, 1979. An edge wave trapped along

a curved coast. (In Japanese: English abstract.) Rept natn. Res. Cent. Disaster Prevent., Tokyo, 21: 75-88.

The effects of arbitrary coastline curvature and slope inclination on the dispersion relations, phase velocities and variations in amplitude and wave number of edge waves are theoretically investigated using varia- tional techniques. Hiratsuka Branch, National Re- search Center for Disaster Prevention, No. 9-2, Nijigahama, Hiratsuka, Kanagawa-ken 254, Japan. (rio)

79:5900 Hukuda, Hisashi, 1979. Solitary Rossby waves in a

two-layer system. Tellus, 31 (2): 161-169.

Wave solutions are presented for a two-layer model with a zonal, baroclinic, mean shear flow. The solutions are consistent with those of Rcdekopp (1977) when the mean shear flow is barotropic. Solitary Rossby waves tend to steepen as a result of vertical shear in the mean flow. Geophysical Institute, Tohoku University, Sendal 980, Japan. (rio)

79:5901 Leonov, A. I., Yu. Z. Miropolsky and R. E. Tamsalu,

1979. Nonlinear stationary internal and surface waves in shallow seas. Tellus, 31 (2): 150-160.