Abstract. In sequential estimation methods often used in oceanic and general climatecalculations of the state and of forecasts, observations act mathematicallyand statistically as source or sink terms in conservation equations for heat, salt, mass, and momentum.These artificial terms obscure the inference of the system's variability or secular changes.Furthermore, for the purposes of calculating changes inimportant functions of state variables such as total mass and energy orvolumetric current transports, results of both filter and smoother-based estimates are sensitive to misrepresentationof a large variety of parameters, including initial conditions, prioruncertainty covariances, and systematic and random errors in observations.Here, toy models of a coupled mass–spring oscillator system and of a barotropic Rossby wave system are used todemonstrate many of the issues that arise from such misrepresentations.Results from Kalman filter estimates and those from finite intervalsmoothing are analyzed.In the filter (and prediction) problem, entry of data leads to violation ofconservation and other invariant rules.A finite interval smoothing method restores the conservation rules, butuncertainties in all such estimation results remain. Convincing trend andother time-dependent determinations in “reanalysis-like” estimates require a full understanding of models, observations, and underlying error structures. Application of smoother-type methods that are designed for optimal reconstruction purposes alleviate some of the issues.
more » « less- Award ID(s):
- 2103942
- PAR ID:
- 10525314
- Publisher / Repository:
- European Geophysical Union
- Date Published:
- Journal Name:
- Ocean Science
- Volume:
- 19
- Issue:
- 4
- ISSN:
- 1812-0792
- Page Range / eLocation ID:
- 1253 to 1275
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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