These reviews of books and other forms of information express the opinions of the individual reviewers and are not necessarily endorsed by the Editorial Board of this Journal. pp. Price: $74.95 hardback and $30.95 paperback.The area of acoustics concerned with nonlinear wave propagation is traditionally called nonlinear acoustics. Several books on this subject are available ͓Zarembo and Krasil'nikov ͑1966͒, Beyer ͑1974͒, Rudenko and Soluyan ͑1975͒, Hamilton and Blackstock ͑1998͔͒. The book by Naugolnykh and Ostrovsky provides yet another perspective on nonlinear acoustics, and it is written by two leading experts who have worked in this field for almost 40 years. Perhaps the more novel feature of their book, which is reflected in the title, is that nonlinear acoustics is considered as a branch of nonlinear wave physics. Such an approach appears to be very fruitful, as it permits the application to acoustics of many concepts and results obtained in other areas of nonlinear wave physics ͑e.g., nonlinear optics͒.The book consists of seven chapters. Chapter 1, entitled ''Nonlinearity, dissipation and dispersion in acoustics,'' describes several models illustrating the combined effects of these three phenomena on acoustic waves in various media. Westervelt, simple-wave, and Burgers equations are developed for nonlinear propagation in gases, liquids, and isotropic solids. Besides these results ͑which can be found in all books on nonlinear acoustics͒, the authors consider media with internal structure having dimensions small compared with a wavelength, such as liquids with gas bubbles and isotropic solids with empty spherical cavities. It is shown how these microinhomogeneities introduce not only additional losses, but also dispersion and a substantial increase in nonlinearity. The chapter concludes with discussion of ''anomalous'' nonlinearities in elastic solids, which are modeled with stress-strain relations not described by a simple power law. Such nonlinearities are associated with dislocations, grains, and microcracks in the medium. Recent developments in this area are very interesting, and it is unfortunate that only a brief survey of these results is presented.In Chapter 2, entitled ''Simple waves and shocks in acoustics,'' evolution of nonlinear plane waves is considered when effects of dissipation and dispersion are much weaker than that of nonlinearity. In this case, initially smooth acoustic perturbations transform eventually to weak shock waves. The chapter presents classical results for shock formation and describes the corresponding evolution of the frequency spectrum within the framework of the simple-wave and Burgers equations. Results for propagation of intense noise are also presented. In our opinion, the most interesting part of this chapter is Section 6, where propagation in media with anomalous nonlinearity is considered. Models are presented for media with two different stress-strain relations. The first, based on a modified Burgers equation, describes propagation in cubically nonlinear media. ...

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Results are presented for experimental laser-scanning investigations of the statistical characteristics of wind-driven ocean waves. The method involves counting the number of specular points during scanning of the sea surface by a narrow laser beam on a moving ship. The data analyzed are the set of specular points recorded along a track traced out by the laser beam as a result of the motion of the ship and the scanning beam. A prominent feature is the large-scale variability of the number of specular points and the self-similar nature of the process over a rather wide range of spatial scales. A fractal analysis of the process shows a clear power-law interval in the spatial spectrum of the distribution of specular points.

An important part of the general problem of the Arctic climate change is the monitoring of the Fram Strait, which lies between Greenland and Spitsbergen. For this reason it is reasonable to apply acoustic methods which are proven to be effective in acoustic ocean thermometry, acoustic tomography, etc. Knowledge of the main peculiarities of sound signal propagation in this region is needed to estimate the feasibility of applying remote acoustic methods. To this end computer simulation of sound signal propagation in the Fram Strait environment was performed, based on oceanographic data obtained by the R/V POLARSTERN expedition. The presence of stable eigenrays in Fram Strait environmental conditions is demonstrated, typical values of acoustic signal travel time fluctuations due to environmental variations are determined, and the temperature effect on the signal travel time variation is considered. Sensitivity estimates for measurement of the average ocean temperature across Fram Strait is considered in two approaches: by calculating travel time changes along selected stable eigenrays, and by determining the cumulative sum of the whole envelope of the signals passed along water-borne paths.

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