Evaluation of the Ensemble Transform Analysis Perturbation Scheme at NRL

Monthly Weather Review;  March 1, 2008 ;     700+ words ......consistent with a user-provided estimate of analysis error covariance. A practical demonstration...Variational Data Assimilation System (NAVDAS) analysis error variance estimates and the Navy Operational...agreement between the ET and NAVDAS analysis error variances. This finding is ...

Decaying singular vectors and their impact on analysis and forecast...

Journal of the Atmospheric Sciences;  October 1, 1998 ;     700+ words ......detrimental effect on the estimation of analysis error. Therefore, for the more realistic...forecasts through a reduction in both the analysis error and the random component of model error...efforts to understand the nature of analysis error and its impact on forecast error have...

A comparison of analysis and forecast correction techniques: Impact of...

Monthly Weather Review;  November 1, 1999 ;     700+ words ......backward-integration calculation results in an analysis-error estimate that projects too weakly onto...backward integration. Therefore, the analysis error estimate will still be dominated by...significantly improved forecast, the analysis error estimate is accurate only when the...

Forecast skill of targeted observations: A singular-vector-based...

Journal of the Atmospheric Sciences;  August 15, 2003 ;     700+ words ......forecast error. The dropsonde-indueed analysis difference has been decomposed into three initial...on average, the dropsonde-indueed analysis difference component in the subspace spanned...10 SVs and the dropsonde-indueed analysis difference component along the pseudoinverse...

The Characteristics of Key Analysis Errors. Part II: The Importance of the...

Monthly Weather Review;  February 1, 2007 ;     700+ words ......Meteorological Centre energy-norm-based key analysis error algorithm, in an attempt to capture...recommendations to improve the key analysis error algorithm are proposed. (ProQuest Information...Centre (CMC) energy-norm-based key analysis error algorithm (Klinker et al. 1998; ...

Comparison between Singular Vectors and Breeding Vectors as Initial...

Monthly Weather Review;  November 1, 2008 ;     700+ words ......rescaling dependent on an estimate of the analysis error variance (masked BV-EPS) were used...obtain the growing component of the analysis error. The breeding vectors are closely related...average more baroclinic than the average analysis error (Bontemps and Kllen 1999). This ...

The Characteristics of Key Analysis Errors. Part III: A Diagnosis of Their...

Monthly Weather Review;  July 1, 2007 ;     700+ words ......initial corrections obtained from the key analysis error algorithm that minimizes the short...see Laroche et al. 2002) is the key analysis error algorithm (Klinker et al. 1998). Until...representative of some part of the analysis error. However, in the first two parts of...

The Characteristics of Key Analysis Errors. Part I: Dynamical Balance and...

Monthly Weather Review;  February 1, 2007 ;     700+ words ......Centre (CMC) energy-norm-based key analysis error algorithm that minimizes short-range...see Laroche et al. 2002b) is the key analysis error algorithm (Klinker et al. 1998, hereafter...the initial corrections from the key analysis error algorithm cannot justifiably be attributed...

Analysis-error statistics of a quasigeostrophic model using...

Monthly Weather Review;  November 1, 2002 ;     700+ words ......conducted to explore the characteristics of analysis error in a quasigeostrophic model. An ensemble...between observational data density and analysis error; there was a much greater reduction...capturing a large percentage of the analysis-error variance, though more members were...

Singular vector calculations with an analysis error variance metric

Monthly Weather Review;  May 1, 2002 ;     700+ words ......norm consistent with an estimate of analysis error variance provided by the Naval Research...penalizes smaller scales. The 20 leading analysis error variance singular vectors explain approximately...metric at initial time is the inverse analysis error covariance matrix, which depends ...

Biased control-variate estimation.(Honoring Alan Pritsker)

IIE Transactions;  March 1, 2001 ;     700+ words ......theta].sup.a] - [[theta].sup.a] as analysis error, to the difference [[theta].sup.a...In classical control variates the analysis error is zero, in which case total error...Variates (BCVs), which allow non-zero analysis error, occur when [[theta].sup.a] is substituted...

Ensemble square root filters*

Monthly Weather Review;  July 1, 2003 ;     700+ words ......low-rank representations of forecast and analysis error covariances. A key element of such...perturbations satisfy the Kalman filter analysis error covariance equation. Deterministic...is its calculation of forecast and analysis error covariances, in addition to the forecasts...

A reduced rank estimate of forecast error variance changes due to...

Journal of the Atmospheric Sciences;  March 1, 2003 ;     700+ words ......guessed diagonal matrix represents the analysis error covariance matrix associated with a...transform Kalman filter (ETKF) method, the analysis error covariance matrix for the modified...by improving the technique's routine analysis error covariance estimate, the skill of the...

Comments on "impact of horizontal diffusion on T21, T42, and T63 singular...

Journal of the Atmospheric Sciences;  March 15, 1999 ;     700+ words ......It will now be argued that if the analysis error probability distribution is isotropic...One may draw the conclusion that the analysis error is not isotropic in phase space with...appears without proof in M96: "If the analysis error probability distribution is isotropic...

The workshop in atmospheric predictability

Bulletin of the American Meteorological Society;  September 1, 2002 ;     700+ words ......perturbations consistent with reasonable assumptions about analysis error characteristics provide an upper bound on the limit of skill...correlations that are consistent with reasonable statistics of analysis error. 4) The dominant horizontal scale at which 50-kPa height...