Variational Methods in Geosciences


Book Description

The last few decades have seen a spectacular growth in the use of variational methods, one of the most classic and elegant methods in physical and mathematical sciences, as powerful tools of optimization and numerical analysis. The tremendous accumulation of information on the use of variational methods in the area of the geosciences, which includes meteorology, oceanography, hydrology, geophysics and seismology, indicated the need for the first symposium on Variational Methods in Geosciences to be organized and held in Norman on October 15-17, 1985. The value of this symposium was enhanced by the number of stimulating and informative papers presented.




Data Assimilation for the Geosciences


Book Description

Data Assimilation for the Geosciences: From Theory to Application brings together all of the mathematical,statistical, and probability background knowledge needed to formulate data assimilation systems in one place. It includes practical exercises for understanding theoretical formulation and presents some aspects of coding the theory with a toy problem. The book also demonstrates how data assimilation systems are implemented in larger scale fluid dynamical problems related to the atmosphere, oceans, as well as the land surface and other geophysical situations. It offers a comprehensive presentation of the subject, from basic principles to advanced methods, such as Particle Filters and Markov-Chain Monte-Carlo methods. Additionally, Data Assimilation for the Geosciences: From Theory to Application covers the applications of data assimilation techniques in various disciplines of the geosciences, making the book useful to students, teachers, and research scientists. Includes practical exercises, enabling readers to apply concepts in a theoretical formulation Offers explanations for how to code certain parts of the theory Presents a step-by-step guide on how, and why, data assimilation works and can be used




Variational Methods in Nonlinear Analysis


Book Description

This well-thought-out book covers the fundamentals of nonlinear analysis, with a particular focus on variational methods and their applications. Starting from preliminaries in functional analysis, it expands in several directions such as Banach spaces, fixed point theory, nonsmooth analysis, minimax theory, variational calculus and inequalities, critical point theory, monotone, maximal monotone and pseudomonotone operators, and evolution problems.







Advanced Data Assimilation for Geosciences


Book Description

Data assimilation aims at determining as accurately as possible the state of a dynamical system by combining heterogeneous sources of information in an optimal way. Generally speaking, the mathematical methods of data assimilation describe algorithms for forming optimal combinations of observations of a system, a numerical model that describes its evolution, and appropriate prior information. Data assimilation has a long history of application to high-dimensional geophysical systems dating back to the 1960s, with application to the estimation of initial conditions for weather forecasts. It has become a major component of numerical forecasting systems in geophysics, and an intensive field of research, with numerous additional applications in oceanography, atmospheric chemistry, and extensions to other geophysical sciences. The physical complexity and the high dimensionality of geophysical systems have led the community of geophysics to make significant contributions to the fundamental theory of data assimilation. This book gathers notes from lectures and seminars given by internationally recognized scientists during a three-week school held in the Les Houches School of physics in 2012, on theoretical and applied data assimilation. It is composed of (i) a series of main lectures, presenting the fundamentals of the most commonly used methods, and the information theory background required to understand and evaluate the role of observations; (ii) a series of specialized lectures, addressing various aspects of data assimilation in detail, from the most recent developments of the theory to the specificities of various thematic applications.




Data Assimilation for the Earth System


Book Description

Data assimilation is the combination of information from observations and models of a particular physical system in order to get the best possible estimate of the state of that system. The technique has wide applications across a range of earth sciences, a major application being the production of operational weather forecasts. Others include oceanography, atmospheric chemistry, climate studies, and hydrology. Data Assimilation for the Earth System is a comprehensive survey of both the theory of data assimilation and its application in a range of earth system sciences. Data assimilation is a key technique in the analysis of remote sensing observations and is thus particularly useful for those analysing the wealth of measurements from recent research satellites. This book is suitable for postgraduate students and those working on the application of data assimilation in meteorology, oceanography and other earth sciences.




Two-Point Boundary Value Problems: Lower and Upper Solutions


Book Description

This book introduces the method of lower and upper solutions for ordinary differential equations. This method is known to be both easy and powerful to solve second order boundary value problems. Besides an extensive introduction to the method, the first half of the book describes some recent and more involved results on this subject. These concern the combined use of the method with degree theory, with variational methods and positive operators. The second half of the book concerns applications. This part exemplifies the method and provides the reader with a fairly large introduction to the problematic of boundary value problems. Although the book concerns mainly ordinary differential equations, some attention is given to other settings such as partial differential equations or functional differential equations. A detailed history of the problem is described in the introduction.· Presents the fundamental features of the method· Construction of lower and upper solutions in problems· Working applications and illustrated theorems by examples· Description of the history of the method and Bibliographical notes




Theory and Approach of Information Retrievals from Electromagnetic Scattering and Remote Sensing


Book Description

Advances in space-borne remote sensing have significantly changed the mankind viewpoint how to observe our own Earth planet. Great amount of remote sensing data and images presents new resources to quantitatively describe and monitor our Earth environment, atmosphere, oceanic and land surfaces. In remote sensing, electromagnetic (EM) scattering, emission and wave propagation, as interaction with the Earth environment, lay the physical basis for understanding and extracting geoscientific information. Study of electromagnetic waves with remote sensing application has become an active and interdisciplinary area. This book presents some new progress on the theoretical and numerical approaches for information retrieval of the remote sensing via EM scattering and emission. We begin in Chapter 1 with the vector radiative transfer (VRT) theory for inhomogeneous scatter media. The VRT takes account of multiple scattering, emission and propagation of random scatter media, and quantitatively leads to insights of elucidating and understanding EM wave-terrain surface interaction. Meanwhile, it is extensively applicable to carrying out data interpretation and validation, and to solving the inverse problem, e.g. iteratively, physically or statistically. In Chapter 1, iterative solutions of multiple scattering and emission from inhomogeneous dense scatter media, and inhomogeneous non-spherical scatter media are discussed. Three-dimensional VRT equation (3D-VRT) for spatially inhomogeneous random scatter media for high resolution observation is also investigated. The polarimetric imagery of synthetic aperture radar (SAR) technology is one of most important advances in space-borne microwave remote sensing during recent decades.




Advances in Geophysics


Book Description

Advances in Geophysics




Scale Space and Variational Methods in Computer Vision


Book Description

This book constitutes the proceedings of the 8th International Conference on Scale Space and Variational Methods in Computer Vision, SSVM 2021, which took place during May 16-20, 2021. The conference was planned to take place in Cabourg, France, but changed to an online format due to the COVID-19 pandemic. The 45 papers included in this volume were carefully reviewed and selected from a total of 64 submissions. They were organized in topical sections named as follows: scale space and partial differential equations methods; flow, motion and registration; optimization theory and methods in imaging; machine learning in imaging; segmentation and labelling; restoration, reconstruction and interpolation; and inverse problems in imaging.