Lagrangian Data Assimilation With Model Error
Sequential data assimilation for a Lagrangian Space LWR model with error propagations
... from data-driven methods which represent a reliable way to gather real time tra ffic information and make predictions for recurring ...situations. Data Assimilation (DA) consists in considering both ...
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Lagrangian data assimilation into layered ocean model
... Chapter 4 introduced the two and a half layer reduced gravity shallow water double gyre flow configuration. It is derived from the Navier-Stokes equations over the three layers and using the hydrostatic assumption for ...
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A Method for Assimilation of Lagrangian Data
... Introduction Lagrangian meters, such as weather balloons and ocean drifters and floats, provide a substantial part of atmospheric and oceanic ...These data are used to reconstruct mean large-scale currents, ...
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Model error estimation in ensemble data assimilation
... bias error affecting all state variables in the same way, one measurement is in theory suf- ficient to estimate and account for the ...the model error affecting these state variables, which is ...
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Representing model error in ensemble data assimilation
... squared error for single forecasts, and give a measure of the average distance between the forecast and observed distribu- tions; the corresponding skill score, the CRPSSs have been computed using a climatological ...
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A Bayesian approach to Lagrangian data assimilation
... In the perfect model scenario, the posterior distribution for the initial state of the system contains all the information that can be extracted from a given realization of observations [r] ...
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The impact of nonlinearity in Lagrangian data assimilation
... 6 Discussion and future directions This paper discusses the effects of nonlinearity on data as- similation. Adopting the Bayesian framework, we work with two different DA methods – namely, the exact Markov chain ...
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On the representation error in data assimilation
... • Error due to unresolved scales and processes is the error associated with spatial and temporal scales, as well as features and processes represented in the observations and not in the NWP ...horizontal ...
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Accounting for model error in strong-constraint 4DVar data assimilation
... the model state vector. The true model state can be obtained at time t i as x t i = M e {i−1}→i (x t i−1 ) + η i , (38) where the vector of model error η i ∼ N (0, Q i ...erroneous ...
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Quantifying the model structural error in carbon cycle data assimilation systems
... the error of process-based terrestrial models, in particular, for global ...carbon-cycle model before any obser- vational constraint, we propose to analyse the statistics of the prior residuals ...
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Ensemble Kalman Filter Data Assimilation in the Presence of Large Model Error
... land data assimilation system (LDAS) compiling high-resolution global land surface analyses from mostly satellite ...through assimilation techniques were forced with observation- based atmospheric ...
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A hybrid particle–ensemble Kalman filter for Lagrangian data assimilation
... assimilating Lagrangian data into ocean ...performing Lagrangian data assimilation are 1) the strong nonlinearity of Lagrangian paths taken by instruments that are ad- vected ...
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Role of forcing uncertainty and background model error characterization in snow data assimilation
... the model and DA ...All model simulations are conducted using the Noah land surface model version ...Land Data Assimilation System Phase 2 (NLDAS-2; Xia et ...This model integra- ...
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Parameter estimation using ensemble based data assimilation in the presence of model error
... of model error in realistic applications ...the model pa- rameters, only optimal values for the parameters can be defined that are the ones that maximize the short-range forecast skill or that ...
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A posteriori error covariances in variational data assimilation
... posteriori error covariances in variational data assimilation ...variational data assimilation for a nonlinear evolution model is formu- lated as an optimal control problem to ...
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On analysis error covariances in variational data assimilation
... analysis error covariance ma- trix with the use of the quasi-Newton BFGS method [26, ...analysis error covariance matrix in the nonlinear ...analysis error variance depends on the different transport ...
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On deterministic error analysis in variational data assimilation
... evolution model to identify the initial ...the error of the optimal solution is derived through the errors of the input data using the Hessian of the misfit ...for error analysis. The ...
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On the interaction of observation and prior error correlations in data assimilation
... Miyoshi et al. (2013) and Terasaki and Miyoshi (2014) showed that the interaction between OECs and the observation operator are very important. In particular, they showed that when the observations are direct ...
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Representation of Model Error in Convective-Scale Data Assimilation: Additive Noise, Relaxation Methods, and Combinations
... mitigating model error in data assimilation for global NWP ...background error covariance when using additive noise with EnKF for data assimilation with global NWP ...
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On optimal solution error covariances in variational data assimilation problems
... of model errors is given in ...posterior error fields in DA is given in ...lution model to estimate the model ...solution error is derived through the errors of the input ...solution ...
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