OPAVAR : The Basics Based on version OPA8.2_VAR2.0 (tagged on 24 June 2005)

Outline

General formulation of OPAVAR

Constructing the control vector

Minimization

Simplifications

The linearized transformation (G) can be summarized as:

Linearized balance operator

Smoothing

Normalization

Some comments on the transformation U

Some comments on the transformation U

Some comments on the transformation U

Some comments on the transformation U

Generalized observation operator cont.

Generalized observation operator cont.

Generalized observation operator cont.

Generalized observation operator cont.

Generalized observation operator cont.

Temporal filtering

Minimization and preconditioning

Minimization and preconditioning

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Proposal for a cost effective minimization strategy using a hybrid 3D-Var/4D-Var

Observation processing, QC and error specification

Automatic QC in OPAVAR

Observation processing, QC and error specification cont.

Observation processing, QC and error specification cont.

Observation processing, QC and error specification cont.

Observation processing, QC and error specification cont.

Assimilation diagnostics

Sample output in coststats.diagnostic 1st outer iteration before the inner loop

Sample output in coststats.diagnostic 1st outer iteration after 1st inner loop

Sample output in coststats.diagnostic 2nd outer iteration before the inner loop

Assimilation diagnostics

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Assimilation diagnostics