ePIC

A regulated localization scheme for ensemble-based Kalman filters

Edit Item Edit Item

General Information:

Citation:
Nerger, L. , Janjic Pfander, T. , Schröter, J. and Hiller, W. (2012): A regulated localization scheme for ensemble-based Kalman filters , Quarterly Journal of the Royal Meteorological Society, 138 , pp. 802-812 . doi: 10.1002/qj.945
Cite this page as:
DOI:
Contact Email:
Download:

[img]
Preview
PDF
paper_v3.pdf

Download (273Kb) | Preview
Cite this document as:
Supplementary Information:

Abstract:

Localization is an essential element of ensemble-based Kalman filters in large-scale systems. Two localization methods are commonly used: Covariance localization and domain localization. The former applies a localizing weight to the forecast covariance matrix while the latter splits the assimilation into local regions in which independent assimilation updates are performed.The domain localization is usually combined with a weighting of the observation error covariance matrix, resulting in a similar localization effect to that of covariance localized filters. In order to improve the performance of domain localization with weighting of the observation errors, a regulated localization scheme is introduced. Twin experiments with the Lorenz-96 model demonstrate that the regulated localization can lead to a significant reduction of the estimation errors as well as increased stability of the assimilation process. In addition, the numerical experiments point out that the combination of covariance localization with a serial processing of observations during the analysis step can destabilize the assimilation process.

Further Details:

Imprint
AWI
Policies:
read more
OAI 2.0:
http://epic.awi.de/cgi/oai2
ePIC is powered by:
EPrints 3