Download or read book Probabilistic Regional Ocean Predictions written by Deepak Narayanan Subramani and published by . This book was released on 2018 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The coastal ocean is a prime example of multiscale nonlinear fluid dynamics. Ocean fields in such regions are complex, with multiple spatial and temporal scales and nonstationary heterogeneous statistics. Due to the limited measurements, there are multiple sources of uncertainties, including the initial conditions, boundary conditions, forcing, parameters, and even the model parameterizations and equations themselves. To reduce uncertainties and allow long-duration measurements, the energy consumption of ocean observing platforms need to be optimized. Predicting the distributions of reachable regions, time-optimal paths, and risk-optimal paths in uncertain, strong and dynamic flows is also essential for their optimal and safe operations. Motivated by the above needs, the objectives of this thesis are to develop and apply the theory, schemes, and computational systems for: (i) Dynamically Orthogonal ocean primitive-equations with a nonlinear free-surface, in order to quantify uncertainties and predict probabilities for four-dimensional (time and 3-d in space) coastal ocean states, respecting their nonlinear governing equations and non-Gaussian statistics; (ii) Stochastic Dynamically Orthogonal level-set optimization to rigorously incorporate realistic ocean flow forecasts and plan energy-optimal paths of autonomous agents in coastal regions; (iii) Probabilistic predictions of reachability, time-optimal paths and risk-optimal paths in uncertain, strong and dynamic flows. For the first objective, we further develop and implement our Dynamically Orthogonal (DO) numerical schemes for idealized and realistic ocean primitive equations with a nonlinear free-surface. The theoretical extensions necessary for the free-surface are completed. DO schemes are researched and DO terms, functions, and operations are implemented, focusing on: state variable choices; DO norms; DO condition for flows with a dynamic free-surface; diagnostic DO equations for pressure, barotropic velocities and density terms; non-polynomial nonlinearities; semi-implicit time-stepping schemes; and re-orthonormalization consistent with leap-frog time marching. We apply the new DO schemes, as well as their theoretical extensions and efficient serial implementation to forecast idealized-to-realistic stochastic coastal ocean dynamics. For the realistic simulations, probabilistic predictions for the Middle Atlantic Bight region, Northwest Atlantic, and northern Indian ocean are showcased. For the second objective, we integrate data-driven ocean modeling with our stochastic DO level-set optimization to compute and study energy-optimal paths, speeds, and headings for ocean vehicles in the Middle Atlantic Bight region. We compute the energy-optimal paths from among exact time-optimal paths. For ocean currents, we utilize a data-assimilative multiscale re-analysis, combining observations with implicit two-way nested multi-resolution primitive-equation simulations of the tidal-to-mesoscale dynamics in the region. We solve the reduced-order stochastic DO level-set partial differential equations (PDEs) to compute the joint probability of minimum arrival-time, vehicle-speed time-series, and total energy utilized. For each arrival time, we then select the vehicle-speed time-series that minimize the total energy utilization from the marginal probability of vehicle-speed and total energy. The corresponding energy-optimal path and headings be obtained through a particle backtracking equation. For the missions considered, we analyze the effects of the regional tidal currents, strong wind events, coastal jets, shelfbreak front, and other local circulations on the energy-optimal paths. For the third objective, we develop and apply stochastic level-set PDEs that govern the stochastic time-optimal reachability fronts and paths for vehicles in uncertain, strong, and dynamic flow fields. To solve these equations efficiently, we again employ their dynamically orthogonal reduced-order projections. We develop the theory and schemes for risk-optimal planning by combining decision theory with our stochastic time-optimal planning equations. The risk-optimal planning proceeds in three steps: (i) obtain predictions of the probability distribution of environmental flows, (ii) obtain predictions of the distribution of exact time-optimal paths for the forecast flow distribution, and (iii) compute and minimize the risk of following these uncertain time-optimal paths. We utilize the new equations to complete stochastic reachability, time-optimal and risk-optimal path planning in varied stochastic quasi-geostrophic flows. The effects of the flow uncertainty on the reachability fronts and time-optimal paths is explained. The risks of following each exact time-optimal path is evaluated and risk-optimal paths are computed for different risk tolerance measures. Key properties of the risk-optimal planning are finally discussed. Theoretically, the present methodologies are PDE-based and compute stochastic ocean fields, and optimal path predictions without heuristics. Computationally, they are several orders of magnitude faster than direct Monte Carlo. Such technologies have several commercial and societal applications. Specifically, the probabilistic ocean predictions can be input to a technical decision aide for a sustainable fisheries co-management program in India, which has the potential to provide environment friendly livelihoods to millions of marginal fishermen. The risk-optimal path planning equations can be employed in real-time for efficient ship routing to reduce greenhouse gas emissions and save operational costs.
Download or read book Statistical Characteristics of Irreversible Predictability Time in Regional Ocean Models written by and published by . This book was released on 2005 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Probabilistic aspects of regional ocean model predictability is analyzed using the probability density function (PDF) of the irreversible predictability time (IPT) (called tau-PDF) computed from an unconstrained ensemble of stochastic perturbations in initial conditions, winds, and open boundary conditions. Two-attractors (a chaotic attractor and a small-amplitude stable limit cycle) are found in the wind-driven circulation. Relationship between attractor's residence time and IPT determines the tau-PDF for the short (up to several weeks) and intermediate (up to two months) predictions. The tau-PDF is usually non-Gaussian but not multi-modal for red-noise perturbations in initial conditions and perturbations in the wind and open boundary conditions. Bifurcation of tau-PDF occurs as the tolerance level varies. Generally, extremely successful predictions (corresponding to the tau-PDF's tail toward large IPT domain) are not outliers and share the same statistics as a whole ensemble of predictions.
Download or read book Seasonal to Decadal Prediction of Marine Ecosystems Opportunities Approaches and Applications written by Mark R. Payne and published by Frontiers Media SA. This book was released on 2019-06-28 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tremendous advances in oceanographic observing and modeling systems over the last decade have led to unprecedented developments in the nature of information available to marine science. While improvements in observational technologies and networks have garnered much attention, remarkable developments in forecasting the ocean have received much less focus. Exploiting this new predictive skill to improve scientific understanding, generate advice and aid in the management of marine resources, is emerging as one of the new challenges of marine science. Translating predictions of the physical environment into biological outcomes, however, is not straightforward. Fisheries scientists, for example, have been trying to understand the links between physics and biology, and generate predictions of variables such as recruitment, for close to a century, with limited success. Nevertheless, spatial distributions and the timing of key events, which have received less focus, are often tightly linked to the physical environment and may have management-relevant applications. The first-such forecasts based on this skill are now starting to emerge. This Frontiers in Marine Science Research Topic provides a snapshot of the state-of-the-art in Marine Ecological Prediction. It covers the opportunities for developing such forecasts, technical approaches that could be employed, and examples where the technology is already being applied. This body of work therefore marks an important milestone on the route to developing this new and exciting field of marine science.
Download or read book Sub seasonal to Seasonal Prediction written by Andrew Robertson and published by Elsevier. This book was released on 2018-10-19 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Gap Between Weather and Climate Forecasting: Sub-seasonal to Seasonal Prediction is an ideal reference for researchers and practitioners across the range of disciplines involved in the science, modeling, forecasting and application of this new frontier in sub-seasonal to seasonal (S2S) prediction. It provides an accessible, yet rigorous, introduction to the scientific principles and sources of predictability through the unique challenges of numerical simulation and forecasting with state-of-science modeling codes and supercomputers. Additional coverage includes the prospects for developing applications to trigger early action decisions to lessen weather catastrophes, minimize costly damage, and optimize operator decisions. The book consists of a set of contributed chapters solicited from experts and leaders in the fields of S2S predictability science, numerical modeling, operational forecasting, and developing application sectors. The introduction and conclusion, written by the co-editors, provides historical perspective, unique synthesis and prospects, and emerging opportunities in this exciting, complex and interdisciplinary field. Contains contributed chapters from leaders and experts in sub-seasonal to seasonal science, forecasting and applications Provides a one-stop shop for graduate students, academic and applied researchers, and practitioners in an emerging and interdisciplinary field Offers a synthesis of the state of S2S science through the use of concrete examples, enabling potential users of S2S forecasts to quickly grasp the potential for application in their own decision-making Includes a broad set of topics, illustrated with graphic examples, that highlight interdisciplinary linkages
Download or read book Ocean Forecasting written by Nadia Pinardi and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Advanced Study Courses in the field of Marine Science and Technology were part of the training programme developed from 1989 until 1999 within MAST, the Marine Science and Technology Programme of the European Union. They were related to the core topics of MAST Programme, marine systems research, extreme marine environments, regional Sea research, coastal systems research and engineering, and marine technology. The main objectives of these study courses were to further advance education in topics at the forefront of scien tific and technological development in Europe, and to improve the communication between students and experienced scientists on a European and international level. Over the years the Programme sponsored around 30 Advanced Study Courses. They took place in ten different member states of the European Union and their contribution in the formation of a European scientific community was significant. They also encouraged exchanges and contacts with several countries around the world such as United States, the third Mediterranean countries and others. The Course on Ocean Forecasting was one ofthe most successful with regard to its con tent, number of applications for participation and students satisfaction. When considering the need for the Advanced Study Course on Ocean Forecast ing, it is important to remember that the Oceans and Seas have always played a central role throughout the history of mankind. This is seen from the times of the ancient civilizations ofEgypt and Greece with the Phoenician traders, to the Viking voyages of exploration and discovery in medieval times.
Download or read book Numerical Weather and Climate Prediction written by Thomas Tomkins Warner and published by Cambridge University Press. This book was released on 2010-12-02 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook provides a comprehensive yet accessible treatment of weather and climate prediction, for graduate students, researchers and professionals. It teaches the strengths, weaknesses and best practices for the use of atmospheric models. It is ideal for the many scientists who use such models across a wide variety of applications. The book describes the different numerical methods, data assimilation, ensemble methods, predictability, land-surface modeling, climate modeling and downscaling, computational fluid-dynamics models, experimental designs in model-based research, verification methods, operational prediction, and special applications such as air-quality modeling and flood prediction. This volume will satisfy everyone who needs to know about atmospheric modeling for use in research or operations. It is ideal both as a textbook for a course on weather and climate prediction and as a reference text for researchers and professionals from a range of backgrounds: atmospheric science, meteorology, climatology, environmental science, geography, and geophysical fluid mechanics/dynamics.
Download or read book Predicting Hydrocarbon Fate in the Ocean Processes Parameterizations and Coupled Modeling written by Robert Hetland and published by Frontiers Media SA. This book was released on 2022-03-18 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-04-30 with total page 755 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.
Download or read book Ocean Surface Waves Their Physics And Prediction Third Edition written by Stanislaw Ryszard Massel and published by World Scientific. This book was released on 2017-09-28 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an extended and substantially updated edition of the previous book editions published in 1996 and 2013 under the same title. The 3rd edition is a one-volume, modern and comprehensive overview of the current knowledge of regular and random ocean surface waves in deep waters and in coastal zones.Since the previous editions many new theoretical advances have been made in the physical understanding and analytical and numerical treatment of various ocean wave problems. The revisions and supplements demanded by these advances have been substantial, therefore the scope of the book has been extended by adding a new chapter and substantially supplementing others.All chapters of the book have been rewritten to include and describe in detail many new discoveries made since the completion of the previous editions. In this 3rd edition a comprehensive and updated overview of the fundamentals of the regular wave mechanics, as well as the spectral and statistical properties of random waves are given. Except for the updated chapters dedicated to tsunami and extreme waves, a new chapter dealing with other types of impulsive waves starting from rest, are also included.The air-sea interaction processes as well as the last improvements in ocean wave modelling and presently available wave prediction models (WAM, WAVEWATCH III, UMWM, NEMO) are thoroughly discussed and their applications are demonstrated. The review of the present ocean observation methods encompasses the modern sea-truthing, as well as applications of data from presently operating marine satellites.In this revised edition, chapters on the behavior of surface waves in the vegetated environments such as coral reef, mangrove forest, seaweed and seagrass areas are substantially extended and updated to include the last discoveries.The explanations in the book are self-contained and detailed enough to capture the interest of the potential readers and to prompt them to explore the research literature. The list of rapidly growing number of the recent papers on the ocean waves has been extended substantially, up to about 900 titles.
Download or read book Experimental Long lead Forecast Bulletin written by and published by . This book was released on 1995 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Probabilistic Models written by Pijush Samui and published by Butterworth-Heinemann. This book was released on 2019-10-05 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Probabilistic Models carefully examines the application of advanced probabilistic models in conventional engineering fields. In this comprehensive handbook, practitioners, researchers and scientists will find detailed explanations of technical concepts, applications of the proposed methods, and the respective scientific approaches needed to solve the problem. This book provides an interdisciplinary approach that creates advanced probabilistic models for engineering fields, ranging from conventional fields of mechanical engineering and civil engineering, to electronics, electrical, earth sciences, climate, agriculture, water resource, mathematical sciences and computer sciences. Specific topics covered include minimax probability machine regression, stochastic finite element method, relevance vector machine, logistic regression, Monte Carlo simulations, random matrix, Gaussian process regression, Kalman filter, stochastic optimization, maximum likelihood, Bayesian inference, Bayesian update, kriging, copula-statistical models, and more. Explains the application of advanced probabilistic models encompassing multidisciplinary research Applies probabilistic modeling to emerging areas in engineering Provides an interdisciplinary approach to probabilistic models and their applications, thus solving a wide range of practical problems
Download or read book Ocean Weather Forecasting written by Eric P. Chassignet and published by Springer Science & Business Media. This book was released on 2006-07-08 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers a wide range of topics and summarizes our present knowledge in ocean modeling, ocean observing systems, and data assimilation. The Global Ocean Data Assimilation Experiment (GODAE) provides a framework for these efforts: a global system of observations, communications, modeling, and assimilation that will deliver regular, comprehensive information on the state of the oceans, engendering wide utility and availability for maximum benefit to the community.
Download or read book Proceedings of 10th International Conference on Coastal and Ocean Engineering written by Dong-Sheng Jeng and published by Springer Nature. This book was released on with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Probability Geometry and Integrable Systems written by Mark Pinsky and published by Cambridge University Press. This book was released on 2008-03-17 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reflects the range of mathematical interests of Henry McKean, to whom it is dedicated.
Download or read book Oceanobs 19 An Ocean of Opportunity Volume II written by Tong Lee and published by Frontiers Media SA. This book was released on 2020-12-31 with total page 629 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.
Download or read book Stochastic Ocean Forecasting with the Dynamically Orthogonal Primitive Equations written by Kyprianos Agioub Gkirgkis and published by . This book was released on 2021 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work focuses on applying the Dynamically Orthogonal Primitive Equations (DO-PE) for realistic high-resolution stochastic ocean forecasting in regions with complex ocean dynamics. In the first part, we identify and test a streamlined process to create multi-region initial conditions for the DO-PE framework, starting from temporally and spatially sparse historical data. The process presented allows us to start from a relatively small but relevant set of measured temperature and salinity historical vertical profiles (on the order of hundreds) and to generate a massive set of initial conditions (on the order of millions) in a stochastic subspace, while still ensuring that the initial statistics respect the physical processes, modeled complex dynamics, and uncertain initial conditions of the examined domain. To illustrate the methodology, two practical examples-one in the Gulf of Mexico and another in the Alboran Sea--are provided, along with a review of the ocean dynamics for each region. In the second part, we present a case study of three massive stochastic DO-PE forecasts, corresponding to ensembles of one million members, in the Gulf of Mexico region. We examine the effect of adding more dynamic DO modes (i.e., stochastic dimensions) and show that it tends to statistical convergence along with an enhancement of the uncertainty captured by the DO forecast realizations, both by increasing the variance of already existing features as well as by adding new uncertain features. We also use this case study to validate the DO-PE methodology for realistic high-resolution probabilistic ocean forecasting. We show good accuracy against equivalent deterministic simulations, starting from the same initial conditions and simulated with the same assumptions, setup, and original ocean model equations. Importantly, by comparing the reduced-order realizations against their deterministic counterparts, we show that the errors due to the DO subspace truncation are much smaller and growing slower than the fields themselves are evolving in time, both in the Root Mean Square Error (RMSE) sense as well as in the 3D multivariate ocean field sense. Based on these observations, we conclude that the DO-PE realizations closely match their full-order equivalents, thus enabling massive forecast ensembles with practically low numerical errors at a tractable computational cost.
Download or read book Advances in Understanding Marine Heatwaves and Their Impacts written by Eric C. J. Oliver and published by Frontiers Media SA. This book was released on 2020-05-05 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
