Determination of optimal nudging coefficients

P. A. Vidard; F.-X. Le Dimet; A. Piacentini

doi:10.3402/tellusa.v55i1.14576

Determination of optimal nudging coefficients

Tellus

Volume 55 (2003): Issue 1

By: P. A. Vidard, F.-X. Le Dimet and A. Piacentini

Open Access

|Jan 2003

Abstract

A four-dimensional variational assimilation (4D-Var) scheme is now widely used by meteorological centres in a operational way. However, most of these applications do not take account of model error. Indeed, the classical 4D-Var with imperfect model formulation is unaffordable for current computational means. This paper presents a low-cost method for dealing with model errors in 4D variational assimilation. This method can be formally compared to a Kalman filter. This new scheme is tested on two configurations: first on a Burger equation, which allows one to calibrate the method, and second on a more relevant shallow-water equations model, both in a twin experiment framework. It is shown that, compared to classical 4D-Var results, this method provides a noticeable improvement.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusa.v55i1.14576 | Journal eISSN: 3035-9554

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Language: English

Page range: 1 - 15

Submitted on: May 28, 2001

Accepted on: Jul 31, 2002

Published on: Jan 1, 2003

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 2003 P. A. Vidard, F.-X. Le Dimet, A. Piacentini, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 55 (2003): Issue 1