734 A. Physical Oceanograph?, OLR (1985) 32 (9)

A290. Physical processes, properties (dif- fusion, turbulence, etc.)

85:4992 Babiano, Armando, Claude Basdevant and Michrle

Larchev~que, 1985. Lagrangian structure func- tion and spectrum of two--dimensional turbulent flow. C. r. Acad. Sci., Paris, (Srr. II)300(6): 195- 198. (In French, English abstract.)

An analysis of the relationships between Lagrangian energy spectrum and second order structure function in 2-D incompressible stationary flows shows that the structure function becomes practically inde- pendent of the spectral slope as soon as the Lagrangian spectrum is nonlocal. The analysis, together with other results, leads to a principle of indetermination for Eulerian and Lagrangian spectra in the nonlocal case. Lab. de Meteor. dynam., Ecole normale superieure, 24, rue Lhomond, 75231 Paris Cedex 05, France.

85:4993 Fernando, H.J.S. and R.R. Long, 1985. On the

nature of the entrainment interlace of a two-layer fluid subjected to zero-mean-shear turbulence. J. Fluid Mech., 151:21-53. W.M. Keck Lab. of Hydraul. and Water Res., Calif. Inst. of Tech., Pasadena, CA 91125, USA.

85:4994 Guillou, Bernard, Wolfgang Mourgues and Doan-

Kim-Son, 1984. Mean velocity field of a turbulent thermal plume. C. r. Acad. Sci., Paris, (Srr. II)299(20):1375-1378. Lab. de Therm. de I'E.N.S.M.A., 20, rue Guillaume-VII, 86034 Poitiers Cedex, France.

85:4995 Zangrando, F. and L.A. Bertram, 1985. The effect of

variable stratification on linear doubly diffusive stability. J. Fluid Mech., 151:55-79. Solar Energy Res. Inst., 1617 Cole Blvd., Golden, CO 80401, USA.

A300. Fluid mechanics

85:4996 Chen, Yingyi, 1984. Conservation of wave action and

evolution in the eddy [applied to hurricane generation and growth]. Scientia sin., (B)27(10): 1059-1068. Inst. of Atmos. Phys., Acad. Sin., Beijing, People's Republic of China.

85:4997 Kirwan, A.D. Jr., 1985. A review of mixture theory

with applications in physical oceanography and meteorology. J. geophys. Res, 90(C2):3265-3283.

In the last 15 years a revolution has occurred in the theoretical continuum approach to mixtures; how- ever, none of this has found its way into the oceanographic or meteorological literature. The modern theory stipulates equations of motion for each constituent; in the classical result it is assumed that the equations of motion for the mixture suffice. The ramifications of this are explored. For the hydrothermal-dynamic description of seawater for purely dynamical purposes the distinction is not important; this may not be true for models of fine and microscale processes. The principal difficulty seems to be the parameterization of mixing by Fickian-type diffusion. For models of ocean seabed interactions it seems clear that the modern theory should be utilized. Some general dynamical models are developed. Dept. of Mar. Sci., Univ. of So. Florida, St. Petersburg, FL, USA.

85:4998 Lindzen, R.S. and J.W. Barker, 1985. Instability and

wave over-reflection in stably stratified shear flow. J. Fluid Mech., 151 : 189-217.

It is shown how regions of enhanced static stability and enhanced damping can destabilize otherwise stable flows. For the ~attering of steady plane waves, only the existence of wave-propagation regions above and below the critical level is neces- sary for over-reflection. A reflecting surface bound- ing the upper wave region may play a crucial role in some cases, perhaps allowing a wave flux through the critical level. An initial-value problem is also considered. Some evidence suggests that the growth rate is related to a characteristic time scale de- pendent only on the shear, which fits the mechanistic picture described. Center for Meteorol. and Phys. Oeeanogr., MIT, Cambridge, MA 02139, USA. (wbo)

85:4999 Shankar, P.N., 1985. A note on a class of exact

solutions in inviscid rotational flows. Z. angew. Math. Phys., 36(1):172-173. Fluid Mech. Div., Natl. Aeronautical Lab., Bangalore 560037, India.

85:5000 Zeytounian, Radyadour, 1984. Initialization of

Bonsstnesq equations for a heavy, stratified and weakly compressible fluid. C. r. Acad. Sci., Paris, (Srr. I)299(20):1033-1036. (In French, English