TY - GEN
AU - A.T. Weaver
AU - C. Deltel
AU - E. Machu
AU - S. Ricci
AU - N. Daget
AB - It is common in meteorological applications of variational assimilation to specify the error covariances of the model background state implicitly via a transformation from model space where variables are highly correlated to a control space where variables can be considered to be approximately uncorrelated. An important part of this transformation is a balance operator which effectively establishes the multivariate component of the error covariances. The use of this technique in ocean data assimilation is less common. This paper describes a balance operator that can be used in a variable transformation for oceanographic applications of three-and four-dimensional variational assimilation. The proposed balance operator has been implemented in an incremental variational data assimilation system for a global ocean general circulation model. Evidence that the balance operator can explain a significant percentage of background-error variance is presented. The multivariate analysis structures implied by the balance operator are illustrated using single observation experiments.
BT - ECMWF Technical Memoranda
CY - Shinfield Park, Reading
DA - 04/2006
DO - 10.21957/a1q77nvm8
LA - eng
M1 - 491
N2 - It is common in meteorological applications of variational assimilation to specify the error covariances of the model background state implicitly via a transformation from model space where variables are highly correlated to a control space where variables can be considered to be approximately uncorrelated. An important part of this transformation is a balance operator which effectively establishes the multivariate component of the error covariances. The use of this technique in ocean data assimilation is less common. This paper describes a balance operator that can be used in a variable transformation for oceanographic applications of three-and four-dimensional variational assimilation. The proposed balance operator has been implemented in an incremental variational data assimilation system for a global ocean general circulation model. Evidence that the balance operator can explain a significant percentage of background-error variance is presented. The multivariate analysis structures implied by the balance operator are illustrated using single observation experiments.
PB - ECMWF
PP - Shinfield Park, Reading
PY - 2006
EP - 19
T2 - ECMWF Technical Memoranda
TI - A multivariate balance operator for variational ocean data assimilation.
UR - https://www.ecmwf.int/node/13007
ER -