Wavelet Approximation in Data Assimilation - Couverture souple

Tangborn, Andrew

Couverture souple

ISBN 10 : 1289289735 ISBN 13 : 9781289289737

Editeur : Bibliogov, 2013

Synopsis

Estimation of the state of the atmosphere with the Kalman filter remains a distant goal because of high computational cost of evolving the error covariance for both linear and nonlinear systems. Wavelet approximation is presented here as a possible solution that efficiently compresses both global and local covariance information. We demonstrate the compression characteristics on the the error correlation field from a global two-dimensional chemical constituent assimilation, and implement an adaptive wavelet approximation scheme on the assimilation of the one-dimensional Burger's equation. In the former problem, we show that 99%, of the error correlation can be represented by just 3% of the wavelet coefficients, with good representation of localized features. In the Burger's equation assimilation, the discrete linearized equations (tangent linear model) and analysis covariance are projected onto a wavelet basis and truncated to just 6%, of the coefficients. A nearly optimal forecast is achieved and we show that errors due to truncation of the dynamics are no greater than the errors due to covariance truncation.

Détails de l'édition

• Éditeur: Bibliogov
• Date d'édition: 2013
• Langue: anglais
• ISBN 10: 1289289735
• ISBN 13: 9781289289737
• Reliure: Broché
• Nombre de pages: 38
• Coordonnées du fabricant: non disponible
• Personne responsable: non disponible