10 One ADAO case is defined by a set of data and of choices, packed together
11 through the user interface of the module. The data are physical
12 measurements that have technically to be available before or during the
13 case execution. The simulation code(s) and the data assimilation or
14 optimization method, and their parameters, has to be chosen, they define
15 the execution properties of the case.
18 One iteration occurs when using iterative optimizers (e.g. 3DVAR), and it
19 is entirely hidden in the main YACS OptimizerLoop Node named
20 "*compute_bloc*". Nevertheless, the user can watch the iterative process
21 through the "*YACS Container Log*" window, which is updated during the
22 process, and using "*Observers*" attached to calculation variables.
25 Keyword to indicate the covariance matrix of *a posteriori* analysis
28 BMA (Background minus Analysis)
29 Difference between the background state and the optimal state estimation,
30 noted as :math:`\mathbf{x}^b - \mathbf{x}^a`.
32 OMA (Observation minus Analysis)
33 Difference between the observations and the result of the simulation based
34 on the optimal state estimation, the analysis, filtered to be compatible
35 with the observation, noted as :math:`\mathbf{y}^o -
36 \mathbf{H}\mathbf{x}^a`.
38 OMB (Observation minus Background)
39 Difference between the observations and the result of the simulation based
40 on the background state, filtered to be compatible with the observation,
41 noted as :math:`\mathbf{y}^o - \mathbf{H}\mathbf{x}^b`.
44 Keyword to indicate the Desroziers-Ivanov parameter measuring the
45 background part consistency of the data assimilation optimal state
46 estimation. Its value can be compared to 1, a "good" estimation leading to
47 a parameter "close" to 1.
50 Keyword to indicate the Desroziers-Ivanov parameter measuring the
51 observation part consistency of the data assimilation optimal state
52 estimation. Its value can be compared to 1, a "good" estimation leading to
53 a parameter "close" to 1.
55 MahalanobisConsistency
56 Keyword to indicate the Mahalanobis parameter measuring the consistency of
57 the data assimilation optimal state estimation. Its value can be compared
58 to 1, a "good" estimation leading to a parameter "close" to 1.
61 The optimal state estimation through a data assimilation or optimization
65 The *a priori* known state, which is not optimal, and is used as a rought
66 estimate, or a "best estimate", before an optimal estimation.
69 Difference between the observations and the result of the simulation based
70 on the background state, filtered to be compatible with the observation.
71 It is similar with OMB in static cases.
74 Keyword to indicate the minimization function, noted as :math:`J`.
77 Keyword to indicate the observation part of the minimization function,
81 Keyword to indicate the background part of the minimization function,