Download or read book Exact Reconstruction of Ocean Bottom Velocity Profiles from Monochromatic Scattering Data written by and published by . This book was released on 1901 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Support for this thesis was provided in part by the education office at WHOI and by the Office of Naval Research.
Download or read book Exact Reconstruction of Ocean Bottom Velocity Profiles from Monochromatic Scattering Data written by André A. Merab and published by . This book was released on 1988 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the theoretical and computational underpinnings of a novel approach to the determination of the acoustic parameters of the ocean bottom using a monochromatic source. The problem is shown to be equivalent to that of the reconstruction of the potential in a Schrodinger equation from the knowledge of the plane-wave reflection coefficient as a function of vertical wavenumber, r(kz) for all real positive k z. First, the reflection coefficient is shown to decay asymptotically at least as fast as (1/kz2) for large kz and is therefore inteqrable. The Gelfand-Levitan inversion procedure is extended to include the case of basement velocity higher than the velocity of sound in water. The neglect of bound states is shown to be justified in both clayey silt and silty clay at the 220 Hz frequency of operation. Three methods for the numerical solution of the integral equation are investigated. The first one is an "Improved Born approximation" wherein the solution is given as a series expansion the first term of which is the Born approximation while the second term represents a substantial and yet easy to implement improvement over Born. The two other methods are based on a discretization of the Gelfand-Levitan integral equation, and both avoid a matrix inversion: one by employing a recursive procedure, and the other by coupling the Gelfand-Levitan equation with a partial differential equation. Bounds are obtained on errors in the solution due either to discretization or to data inaccuracy. These methods are tested on synthetic data obtained from known geoacoustic models of the ocean bottom. Results are found to be very accurate particularly at the top of the sediment layer with resolution of less than the wavelength of the acoustic source in the water. Several effects are investigated, such as sampling, attenuation, and noise. Also examined is the gradual restriction of the reflection coefficient to a finite range of vertical wave numbers and the consequent progressive deterioration of the reconstruction. The analysis shows how to reconstruct velocity profiles in the presence of density variation when the experiment is conducted at two frequencies. Our results provide a good understanding of the issues involved in conducting a monochromatic deep ocean bottom experiment and constitute a promising technique for processing the experimental data when it becomes available.
Download or read book Oceanic Abstracts written by and published by . This book was released on 1988 with total page 780 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanic Abstracts with Indexes written by and published by . This book was released on 1988 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aquatic Sciences and Fisheries Abstracts written by and published by . This book was released on 1988 with total page 836 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1989-07 with total page 1314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fluid Mechanical Measurements Within the Boundary Layer Over the Northern California Continental Shelf During STRESS written by and published by . This book was released on 1993 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanographic and Geophysical Tomography written by Yves Desaubies and published by . This book was released on 1990 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: In geophysics, tomography is a technique which deduces some physical properties of the medium from the perturbations encountered by waves propagating through it. Thus tomography draws on a variety of disciplines, such as wave propagation in heterogeneous media, statistical estimation and inverse theory, and numerical modeling. These subjects take different forms when applied to solid Earth geophysics or to physical oceanography. The aim of the 50th session of the Les Houches Summer School was to present in detail theoretical and practical aspects of tomography in geophysics and oceanography. One of the goals was to bring together students and practitioners of the two fields to teach, discuss and exchange ideas on all the components of tomography, to point out common approaches and to contrast various specific applications. The resulting book shows the diversity and vitality of this field of research and underlines the variety of disciplines involved.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Annual Report written by Woods Hole Oceanographic Institution and published by . This book was released on 1983 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Curricula in the Atmospheric Oceanic and Related Sciences written by and published by . This book was released on 1988 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book CTD Observations Off Northern California During the Shelf Mixed Layer Experiment SMILE May 1989 written by Richard Limeburner and published by . This book was released on 1989 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt: CTD observations were made off the northern California coast during R/V Wecoma cruise W8905 May 5-14, 1989 as part of the Shelf Mixed Layer Experiment (SMILE). The surveys consisted of two sampling plans - a large-scale grid of four cross-shelf transects extending to both sides of Point Arena and Point Reyes, and a small-scale grid of six cross-shelf transects located near the central SMILE mooring site. All of the cross-shelf transects extended beyond the shelf break and the maximum sampling depth at each station was near-bottom or 1500 m. The average along-shelf separation between cross-shelf transects was about 15 km for the small-scale surveys and 50 km for the large-scale grid. The primary objectives of the hydrographic measurement program were to observe and characterize the temperature, salinity, density, and light transmission fields and their temporal and spatial variability in the surface boundary layer along the continental shelf and slope near the SMILE moored array, and to acquire estimates of the cross- and along-shelf scales over which the mixed-layer depth varies. This report presents a summary in graphic and tabular form of the hydrographic observations made during cruise W8905 on the R/V Wecoma.
Download or read book Petroleum Abstracts written by and published by . This book was released on 1987-04 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petroleum Abstracts Literature and Patents written by and published by . This book was released on 1987 with total page 1348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Interaction of Ocean Waves and Wind written by Peter Janssen and published by Cambridge University Press. This book was released on 2004-10-28 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book was published in 2004. The Interaction of Ocean Waves and Wind describes in detail the two-way interaction between wind and ocean waves and shows how ocean waves affect weather forecasting on timescales of 5 to 90 days. Winds generate ocean waves, but at the same time airflow is modified due to the loss of energy and momentum to the waves; thus, momentum loss from the atmosphere to the ocean depends on the state of the waves. This volume discusses ocean wave evolution according to the energy balance equation. An extensive overview of nonlinear transfer is given, and as a by-product the role of four-wave interactions in the generation of extreme events, such as freak waves, is discussed. Effects on ocean circulation are described. Coupled ocean-wave, atmosphere modelling gives improved weather and wave forecasts. This volume will interest ocean wave modellers, physicists and applied mathematicians, and engineers interested in shipping and coastal protection.
Download or read book Real time Coastal Observing Systems for Marine Ecosystem Dynamics and Harmful Algal Blooms written by Babin, Marcel and published by UNESCO. This book was released on 2008-06-05 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proliferation of harmful phytoplankton in marine ecosystems can cause massive fish kills, contaminate seafood with toxins, impact local and regional economies and dramatically affect ecological balance. Real-time observations are essential for effective short-term operational forecasting, but observation and modelling systems are still being developed. This volume provides guidance for developing real-time and near real-time sensing systems for observing and predicting plankton dynamics, including harmful algal blooms, in coastal waters. The underlying theory is explained and current trends in research and monitoring are discussed.Topics covered include: coastal ecosystems and dynamics of harmful algal blooms; theory and practical applications of in situ and remotely sensed optical detection of microalgal distributions and composition; theory and practical applications of in situ biological and chemical sensors for targeted species and toxin detection; integrated observing systems and platforms for detection; diagnostic and predictive modelling of ecosystems and harmful algal blooms, including data assimilation techniques; observational needs for the public and government; and future directions for research and operations.
