Format:
1 Online-Ressource (xiv, 433 pages)
,
digital, PDF file(s)
ISBN:
9780511666926
Series Statement:
Cambridge monographs on mechanics
Content:
The problem of ocean acoustic tomography is to infer from precise measurements of travel time, or other properties of acoustic propagation, the state of the ocean traversed by a sound field. Tomography takes advantage of two facts: that travel time and other measurable acoustic parameters are functions of temperature, water velocity, and other parameters of oceanographic interest, and can be interpreted to provide information about the intervening ocean using inverse methods; and that the ocean is virtually transparent to low-frequency sound, so that signals can be transmitted over distances of many thousands of kilometres. It is therefore possible to prepare a practical system of transmitters and receivers to interpret the behaviour of the oceans. This book gives a comprehensive presentation of the underlying oceanography and mathematics necessary to understand and develop such a system. It covers the forward and inverse tomography problem, as well as numerous models for data interpretation. Also included is an epilogue outlining the history of tomographic techniques. It should prove a valuable resource to oceanographers and climatologists, as well as applied mathematicians and engineers interested in applications of fluid mechanics tools
Content:
1. The tomography problem -- 1.1 Ocean acoustics -- 1.2 The forward and inverse problems -- 1.3 Vertical slice: A numerical example -- 1.4 Horizontal slice -- 1.5 Estimation through time -- 1.6 Testing -- 1.7 Comparisons and comments -- 2. The forward problem: Range-independent -- 2.1 The ocean sound channel -- 2.2 Sound-speed -- Ray representation -- 2.3 Ray theory -- 2.4 Ray diagram -- 2.5 Action variable -- 2.6 Structure of ray arrivals -- 2.7 Ray weighting -- 2.8 Ray perturbations -- 2.9 Parametric and functional perturbation -- Mode representation -- 2.10 Modes -- 2.11 WKBJ approximation: Ray/mode equivalence -- 2.12 Modal t, z-display -- 2.13 Ambiguity relations -- 2.14 Modal perturbations -- 2.15 Perturbation models -- Observations -- 2.16 Observations -- Appendix -- 2.17 Polar (Adiabatic) profile -- 2.18 Temperate (Canonical) profile -- 3. Currents -- 3.1 Ray theory in an inhomogeneous moving medium -- 3.2 Travel-time perturbations -- 3.3 Geostrophic flow -- 3.4 Circulation, vorticity, and divergence -- 3.5 Nonreciprocity -- 3.6 Reciprocal-transmission experiments -- 4. The forward problem: Range-dependent -- 4.1 Adiabatic range dependence -- 4.2 Loop resonance -- 4.3 Mesoscale variability -- 4.4 Internal waves -- 4.5 Ray chaos -- 4.6 Modes in a range-dependent profile -- 4.7 Horizontal refraction -- 5. Observational methods -- 5.1 The sonar equation -- 5.2 Pulse compression -- 5.3 Travel time -- 5.4 Vertical arrival angle -- 5.5 Doppler -- 5.6 Timekeeping -- 5.7 Positioning -- 5.8 Data treatment -- Appendix -- 5.9 Binary m-sequences -- 6. The inverse problem: Data-oriented -- 6.1 Introduction -- 6.2 Representation -- 6.3 Least-squares -- 6.4 Singular-value solution and decomposition -- 6.5 Gauss-Markov estimation -- 6.6 Variant linear methods -- 6.7 Recursive solutions -- 6.8 Nonlinear problems and methods -- 6.9 Inversions in practice -- 6.10 Summary comments -- 7. The inverse problem: Model-oriented -- 7.1 Introduction: The use of models -- 7.2 State estimation and model identification -- 7.3 State estimation: Practice -- 7.4 Extensions: Control, identification, and adaptive methods -- 8. The basin scale -- 8.1 Climate variability -- 8.2 Some experimental considerations -- 8.3 A brief historical review -- 8.4 Low-frequency propagation at very long ranges -- 8.5 Refracted geodesics -- 8.6 Spheroidal caustics -- 8.7 Mode stripping and repopulation -- 8.8 Basin reverberation -- 8.9 The future of basin-scale tomography -- Epilogue: The science of ocean acoustic tomography -- Appendix -- A.A personal chronicle -- B. Ocean acoustic propagation atlas
Note:
Title from publisher's bibliographic system (viewed on 05 Oct 2015)
Additional Edition:
ISBN 9780521470957
Additional Edition:
ISBN 9780521115360
Additional Edition:
Erscheint auch als Druck-Ausgabe ISBN 9780521470957
Language:
English
DOI:
10.1017/CBO9780511666926
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