Mathematical Study of Degenerate Boundary Layers: A Large Scale Ocean Circulation Problem

Mathematical Study of Degenerate Boundary Layers: A Large Scale Ocean Circulation Problem PDF Author: Anne-Laure Dalibard
Publisher: American Mathematical Soc.
ISBN: 1470428350
Category : Mathematics
Languages : en
Pages : 118

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Book Description
This paper is concerned with a complete asymptotic analysis as $E \to 0$ of the Munk equation $\partial _x\psi -E \Delta ^2 \psi = \tau $ in a domain $\Omega \subset \mathbf R^2$, supplemented with boundary conditions for $\psi $ and $\partial _n \psi $. This equation is a simple model for the circulation of currents in closed basins, the variables $x$ and $y$ being respectively the longitude and the latitude. A crude analysis shows that as $E \to 0$, the weak limit of $\psi $ satisfies the so-called Sverdrup transport equation inside the domain, namely $\partial _x \psi ^0=\tau $, while boundary layers appear in the vicinity of the boundary.

Mathematical Study of Degenerate Boundary Layers: A Large Scale Ocean Circulation Problem

Mathematical Study of Degenerate Boundary Layers: A Large Scale Ocean Circulation Problem PDF Author: Anne-Laure Dalibard
Publisher: American Mathematical Soc.
ISBN: 1470428350
Category : Mathematics
Languages : en
Pages : 118

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Book Description
This paper is concerned with a complete asymptotic analysis as $E \to 0$ of the Munk equation $\partial _x\psi -E \Delta ^2 \psi = \tau $ in a domain $\Omega \subset \mathbf R^2$, supplemented with boundary conditions for $\psi $ and $\partial _n \psi $. This equation is a simple model for the circulation of currents in closed basins, the variables $x$ and $y$ being respectively the longitude and the latitude. A crude analysis shows that as $E \to 0$, the weak limit of $\psi $ satisfies the so-called Sverdrup transport equation inside the domain, namely $\partial _x \psi ^0=\tau $, while boundary layers appear in the vicinity of the boundary.

On the Asymptotic Analysis of Large-scale Ocean Circulation

On the Asymptotic Analysis of Large-scale Ocean Circulation PDF Author: W. P. M. de Ruijter
Publisher:
ISBN:
Category : Asymptotes
Languages : en
Pages : 142

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Book Description


The Theory of Large-Scale Ocean Circulation

The Theory of Large-Scale Ocean Circulation PDF Author: R. M. Samelson
Publisher: Cambridge University Press
ISBN: 1139499009
Category : Science
Languages : en
Pages : 209

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Book Description
Mounting evidence that human activities are substantially modifying the Earth's climate brings a new imperative to the study of the ocean's large-scale circulation. This textbook provides a concise but comprehensive introduction to the theory of large-scale ocean circulation, as it is currently understood and established. Students and instructors will benefit from the carefully chosen chapter-by-chapter exercises. This advanced textbook is invaluable for graduate students and researchers in the fields of oceanic, atmospheric and climate sciences, and other geophysical scientists, as well as physicists and mathematicians with a quantitative interest in the planetary fluid environment.

Mathematical Modelling of Ocean Circulation

Mathematical Modelling of Ocean Circulation PDF Author: Guriĭ Ivanovich Marchuk
Publisher: Springer
ISBN:
Category : Mathematics
Languages : en
Pages : 320

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Book Description
The problems of ocean dynamics present more and more com plex tasks for investigators, based on the continuously sophisti cation of theoretical models, which are applied with the help of universal and efficient algorithms of numerical mathematics. The present level of our knowledge in the field of mathemat ical physics and numerical mathematics allows one to give rather complete theoretical analysis of basic statements of problems as well as numerical algorithms. Our task is to perform such analy sis and also to analyze the results of calculations in order to improve our knowledge of the mechanism of large-scale hy drological processes occurring in the World Ocean. The new level of numerical mathematics has essentially influenced , the formation of new solution methods of ocean dynamics prob lems, among which an important one is the splitting method, which has been already widely practised in various fields of science and engineering. A number of monographs by N. N. Yanenko, A. A. Samarsky, G.!. Marchuk (Rozhdestvensky and Yanenko 1968; Samarsky and Andreyev 1976; Marchuk 1970, 1980b) and others are devoted to the description of this methods. But the methods of the splitting theory require extensive creative work for their application to concrete problems, which are peculiar, as a rule, in problem formulation. The success of the application of these methods is related to the deep understanding of the essence of the described processes. In the last decades fundamental works of Arakawa, K.

Perihelia Reduction and Global Kolmogorov Tori in the Planetary Problem

Perihelia Reduction and Global Kolmogorov Tori in the Planetary Problem PDF Author: Gabriella Pinzari
Publisher: American Mathematical Soc.
ISBN: 1470441020
Category : Mathematics
Languages : en
Pages : 104

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Book Description
The author proves the existence of an almost full measure set of -dimensional quasi-periodic motions in the planetary problem with masses, with eccentricities arbitrarily close to the Levi–Civita limiting value and relatively high inclinations. This extends previous results, where smallness of eccentricities and inclinations was assumed. The question had been previously considered by V. I. Arnold in the 1960s, for the particular case of the planar three-body problem, where, due to the limited number of degrees of freedom, it was enough to use the invariance of the system by the SO(3) group. The proof exploits nice parity properties of a new set of coordinates for the planetary problem, which reduces completely the number of degrees of freedom for the system (in particular, its degeneracy due to rotations) and, moreover, is well fitted to its reflection invariance. It allows the explicit construction of an associated close to be integrable system, replacing Birkhoff normal form, a common tool of previous literature.

Strichartz Estimates and the Cauchy Problem for the Gravity Water Waves Equations

Strichartz Estimates and the Cauchy Problem for the Gravity Water Waves Equations PDF Author: T. Alazard
Publisher: American Mathematical Soc.
ISBN: 147043203X
Category : Cauchy problem
Languages : en
Pages : 108

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Book Description
This memoir is devoted to the proof of a well-posedness result for the gravity water waves equations, in arbitrary dimension and in fluid domains with general bottoms, when the initial velocity field is not necessarily Lipschitz. Moreover, for two-dimensional waves, the authors consider solutions such that the curvature of the initial free surface does not belong to L2. The proof is entirely based on the Eulerian formulation of the water waves equations, using microlocal analysis to obtain sharp Sobolev and Hölder estimates. The authors first prove tame estimates in Sobolev spaces depending linearly on Hölder norms and then use the dispersive properties of the water-waves system, namely Strichartz estimates, to control these Hölder norms.

Bellman Function for Extremal Problems in BMO II: Evolution

Bellman Function for Extremal Problems in BMO II: Evolution PDF Author: Paata Ivanisvili
Publisher: American Mathematical Soc.
ISBN: 1470429543
Category : Mathematics
Languages : en
Pages : 148

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Book Description
In a previous study, the authors built the Bellman function for integral functionals on the space. The present paper provides a development of the subject. They abandon the majority of unwanted restrictions on the function that generates the functional. It is the new evolutional approach that allows the authors to treat the problem in its natural setting. What is more, these new considerations lighten dynamical aspects of the Bellman function, in particular, the evolution of its picture.

Measure and Capacity of Wandering Domains in Gevrey Near-Integrable Exact Symplectic Systems

Measure and Capacity of Wandering Domains in Gevrey Near-Integrable Exact Symplectic Systems PDF Author: Laurent Lazzarini
Publisher: American Mathematical Soc.
ISBN: 147043492X
Category : Domains of holomorphy
Languages : en
Pages : 106

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Book Description
A wandering domain for a diffeomorphism of is an open connected set such that for all . The authors endow with its usual exact symplectic structure. An integrable diffeomorphism, i.e., the time-one map of a Hamiltonian which depends only on the action variables, has no nonempty wandering domains. The aim of this paper is to estimate the size (measure and Gromov capacity) of wandering domains in the case of an exact symplectic perturbation of , in the analytic or Gevrey category. Upper estimates are related to Nekhoroshev theory; lower estimates are related to examples of Arnold diffusion. This is a contribution to the “quantitative Hamiltonian perturbation theory” initiated in previous works on the optimality of long term stability estimates and diffusion times; the emphasis here is on discrete systems because this is the natural setting to study wandering domains.

On Fusion Systems of Component Type

On Fusion Systems of Component Type PDF Author: Michael Aschbacher
Publisher: American Mathematical Soc.
ISBN: 1470435209
Category :
Languages : en
Pages : 182

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Book Description
This memoir begins a program to classify a large subclass of the class of simple saturated 2-fusion systems of component type. Such a classification would be of great interest in its own right, but in addition it should lead to a significant simplification of the proof of the theorem classifying the finite simple groups. Why should such a simplification be possible? Part of the answer lies in the fact that there are advantages to be gained by working with fusion systems rather than groups. In particular one can hope to avoid a proof of the B-Conjecture, a important but difficult result in finite group theory, established only with great effort.

Fusion of Defects

Fusion of Defects PDF Author: Arthur Bartels
Publisher: American Mathematical Soc.
ISBN: 1470435233
Category : Generalized spaces
Languages : en
Pages : 102

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Book Description
Conformal nets provide a mathematical model for conformal field theory. The authors define a notion of defect between conformal nets, formalizing the idea of an interaction between two conformal field theories. They introduce an operation of fusion of defects, and prove that the fusion of two defects is again a defect, provided the fusion occurs over a conformal net of finite index. There is a notion of sector (or bimodule) between two defects, and operations of horizontal and vertical fusion of such sectors. The authors' most difficult technical result is that the horizontal fusion of the vacuum sectors of two defects is isomorphic to the vacuum sector of the fused defect. Equipped with this isomorphism, they construct the basic interchange isomorphism between the horizontal fusion of two vertical fusions and the vertical fusion of two horizontal fusions of sectors.