A comparison of combined data assimilation and machine learning methods for offline and online model error correction

A Farchi, M Bocquet, P Laloyaux, M Bonavita… - Journal of computational …, 2021 - Elsevier
Recent studies have shown that it is possible to combine machine learning methods with
data assimilation to reconstruct a dynamical system using only sparse and noisy …

Revising the stochastic iterative ensemble smoother

PN Raanes, AS Stordal… - Nonlinear Processes in …, 2019 - npg.copernicus.org
Ensemble randomized maximum likelihood (EnRML) is an iterative (stochastic) ensemble
smoother, used for large and nonlinear inverse problems, such as history matching and data …

[HTML][HTML] A square-root, dual-resolution 3DEnVar for the AROME Model: Formulation and evaluation on a summertime convective period

Y Michel, P Brousseau - Monthly Weather Review, 2021 - journals.ametsoc.org
A three-dimensional ensemble-variational (3DEnVar) data assimilation algorithm has been
developed for the high-resolution AROME NWP system. Building on previous work on …

A fast, single-iteration ensemble Kalman smoother for sequential data assimilation

C Grudzien, M Bocquet - Geoscientific Model Development, 2022 - gmd.copernicus.org
Ensemble variational methods form the basis of the state of the art for nonlinear, scalable
data assimilation, yet current designs may not be cost-effective for real-time, short-range …

An iterative ensemble Kalman smoother in presence of additive model error

A Fillion, M Bocquet, S Gratton, S Gürol… - SIAM/ASA Journal on …, 2020 - SIAM
Ensemble variational methods are being increasingly used in the field of geophysical data
assimilation. Their efficiency comes from the combined use of ensembles, which provide …

A kernel extension of the Ensemble Transform Kalman Filter

S Mauran, S Mouysset, E Simon, L Bertino - International Conference on …, 2023 - Springer
Data assimilation methods are mainly based on the Bayesian formulation of the estimation
problem. For cost and feasibility reasons, this formulation is usually approximated by …

[HTML][HTML] Ensemble transport smoothing. Part II: Nonlinear updates

M Ramgraber, R Baptista, D McLaughlin… - Journal of Computational …, 2023 - Elsevier
Smoothing is a specialized form of Bayesian inference for state-space models that
characterizes the posterior distribution of a collection of states given an associated …

Batch seismic inversion using the iterative ensemble Kalman smoother

M Gineste, J Eidsvik - Computational Geosciences, 2021 - Springer
An ensemble-based method for seismic inversion to estimate elastic attributes is considered,
namely the iterative ensemble Kalman smoother. The main focus of this work is the …

[PDF][PDF] Paris-Est

A Fillion - 2019 - cerea-lab.fr
L'assimilation de données consiste à calculer une estimation de l'état d'un système
physique. Cette estimation doit alors combiner de façon optimale des observations …

Novel optimisation methods for data assimilation

MH Kaouri - 2021 - centaur.reading.ac.uk
Data assimilation (DA) is a technique used to estimate the state of a dynamical system. In
DA, a prior estimate (background state) is combined with observations to estimate the initial …