Acoustic sensing techniques for the shallow water environment: inversiton methods and experiments

Andrea Caiti, N. Ross Chapman, Jean-Pierre Hermand, Sérgio M. Jesus1402043724, 9781402043727, 9781402043864

Acoustic remote sensing of the ocean environment has seen a remarkable progress in the last ten–fifteen year as a result of an increasing understanding of the experimental techniques and procedures and of the subtleties of the interaction of sound with complex physical and biological processes. This is particularly true in the shallow water environment, where acoustic methods have the potential to allow for a fast and accurate characterization and assessment of the environment. To review the state of the art and the research progress in the field, a workshop was held in the island of Ischia, Italy, in June 2004. Special emphasis has been placed on the experimental applications, to realistically assess their potential and capabilities of the methods proposed. This volume, based on the workshop presentations, include a range of diverse and innovative applications, as well as comparisons in the field among competing approaches and review papers.

The invited contributions range from ocean acoustic tomography to estimation of the seabed and subbottom properties, to marine biology; ambient noise in the ocean is increasingly being investigated as a replacement for traditional acoustic source, to make acoustic inversion even less invasive and more environmentally friendly as a methodology to probe the ocean.

Audience: This book is primarily intended for physicists and engineers working in underwater acoustics and oceanic engineering. It will also be of interest to marine biologists, geophysicists and oceanographers as potential users of the methodologies and techniques described in the book contributions.

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Table of contents :
Table of Contents……Page 8
Preface……Page 10
Acknowledgements……Page 12
On the assessment of geoacoustic parameters in shallow water environments……Page 13
Bayesian inversion of seabed reflection data……Page 28
Backpropagation techniques in ocean acoustic inversion: time reversal, retrogation and adjoint modelling – A review……Page 39
Acoustic inversion at low kHz frequencies using an active, vertical line array……Page 57
Dispersion of broadband acoustic normal modes in the context of long range sediment tomography……Page 66
Characterization of local seabed properties using synthesized horizontal array data……Page 82
Characterization of a range-dependent environment from towed array data……Page 96
Accounting for bias in horizontal wavenumber estimates due to source motion……Page 107
Acoustic clutter from buried submarine mud volcanoes……Page 117
Nonlinear acoustical methods in the detection of gassy sediments……Page 133
Acoustic scattering from submerged and buried objects……Page 145
High-frequency bistatic scattering experiments using proud and buried targets……Page 162
A sediment probe for the rapid assessment of seabed characteristics……Page 178
Continuous acoustic monitoring of physiological and environmental processes in seagrass prairies with focus on photosynthesis……Page 189
Shallow water tomography in a highly variable scenario……Page 203
Inversions of reflection loss measurements of a smooth water/sand interface……Page 218
Estimation of transmission loss and its uncertainty……Page 237
A forward model for geoacoustic inversion based on ray tracing and plane-wave reflection coefficients……Page 245
Inversion of the propeller harmonics from a light aircraft for the geoacoustic properties of marine sediments……Page 260
Inversion of shallow water ambient noise data by means of differential evolution as a global search method……Page 267
Reflection loss and sub-bottom profiling with ambient noise……Page 282
Inversion of geoacoustic model parameters using ship radiated noise……Page 290
Matched-field processing of humpback whale song off eastern Australia……Page 304
Inversions of horizontal and vertical line array data for the estimation of geoacoustic model parameters……Page 309
Issues of environmental variability in inverse problems in ocean……Page 321
Author Index……Page 329
M……Page 330
Y……Page 331