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Related papers: Multi-Scale Data Assimilation in Turbulent Models

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This paper presents an innovative Reduced-Order Model (ROM) for merging experimental and simulation data using Data Assimilation (DA) to estimate the "True" state of a fluid dynamics system, leading to more accurate predictions. Our…

Computational Engineering, Finance, and Science · Computer Science 2025-07-03 Paul Jeanney , Ashton Hetherington , Shady E. Ahmed , David Lanceta , Susana Saiz , José Miguel Perez , Soledad Le Clainche

The ensemble Kalman filter (EnKF) is a data assimilation technique that uses an ensemble of models, updated with data, to track the time evolution of a usually non-linear system. It does so by using an empirical approximation to the…

Applications · Statistics 2021-03-12 Elizabeth Hou , Earl Lawrence , Alfred O. Hero

Data assimilation is a method of uncertainty quantification to estimate the hidden true state by updating the prediction owing to model dynamics with observation data. As a prediction model, we consider a class of nonlinear dynamical…

Statistics Theory · Mathematics 2026-03-05 Kota Takeda , Takashi Sakajo

A physics-based methodology for the determination of the localization function for the Ensemble Kalman Filter (EnKF) is proposed. The spatial features of such function evolve dynamically over time according to the relevant instantaneous…

Fluid Dynamics · Physics 2025-11-13 Sarp Er , Marcello Meldi

Ensemble methods such as the Ensemble Kalman Filter (EnKF) are widely used for data assimilation in large-scale geophysical applications, as for example in numerical weather prediction (NWP). There is a growing interest for physical models…

Applications · Statistics 2018-08-01 Sylvain Robert , Hans R. Künsch

We study the ensemble Kalman filter (EnKF) algorithm for sequential data assimilation in a general situation, that is, for nonlinear forecast and measurement models with non-additive and non-Gaussian noises. Such applications traditionally…

Methodology · Statistics 2018-08-17 Weixuan Li , W. Steven Rosenthal , Guang Lin

Working with a two-stage ice sheet model, we explore how statistical data assimilation methods can be used to improve predictions of glacier melt and relatedly, sea level rise. We find that the EnKF improves model runs initialized using…

Dynamical Systems · Mathematics 2023-05-23 Emily Corcoran , Logan Knudsen , Talea Mayo , Hannah Park-Kaufmann , Alexander Robel

Data assimilation plays a key role in large-scale atmospheric weather forecasting, where the state of the physical system is estimated from model outputs and observations, and is then used as initial condition to produce accurate future…

Methodology · Statistics 2018-02-13 Azam Moosavi , Ahmed Attia , Adrian Sandu

Data assimilation combines information from models, measurements, and priors to estimate the state of a dynamical system such as the atmosphere. The Ensemble Kalman filter (EnKF) is a family of ensemble-based data assimilation approaches…

Computational Engineering, Finance, and Science · Computer Science 2014-12-09 Ahmed Attia , Adrian Sandu

A data-driven investigation of the flow around a high-rise building is performed combining heterogeneous experimental samples and RANS CFD. The coupling is performed using techniques based on the Ensemble Kalman Filter (EnKF), including…

Fluid Dynamics · Physics 2023-01-27 Lucas Villanueva , Miguel Martinez Valero , Anina Sarkic Glumac , Marcello Meldi

Monitoring carbon dioxide (CO2) injected and stored in subsurface reservoirs is critical for avoiding failure scenarios and enables real-time optimization of CO2 injection rates. Sequential Bayesian data assimilation (DA) is a statistical…

Geophysics · Physics 2024-10-22 Grant Bruer , Abhinav Prakash Gahlot , Edmond Chow , Felix Herrmann

We present a new type of the EnKF for data assimilation in spatial models that uses diagonal approximation of the state covariance in the wavelet space to achieve adaptive localization. The efficiency of the new method is demonstrated on an…

Dynamical Systems · Mathematics 2011-03-01 Jonathan D. Beezley , Jan Mandel , Loren Cobb

This paper studies multiplicative inflation: the complementary scaling of the state covariance in the ensemble Kalman filter (EnKF). Firstly, error sources in the EnKF are catalogued and discussed in relation to inflation; nonlinearity is…

Data Analysis, Statistics and Probability · Physics 2019-03-27 Patrick N. Raanes , Marc Bocquet , Alberto Carrassi

The Ensemble Kalman filter assumes the observations to be Gaussian random variables with a pre-specified mean and variance. In practice, observations may also have detection limits, for instance when a gauge has a minimum or maximum value.…

Optimization and Control · Mathematics 2018-11-14 Abhishek Shah , Mohamad El Gharamti , Laurent Bertino

Recent advances in data assimilation (DA) have focused on developing more flexible approaches that can better accommodate nonlinearities in models and observations. However, it remains unclear how the performance of these advanced methods…

Atmospheric and Oceanic Physics · Physics 2025-05-08 Zixiang Xiong , Siming Liang , Feng Bao , Guannan Zhang , Hristo G. Chipilski

Ensemble transform Kalman filtering (ETKF) data assimilation is often used to combine available observations with numerical simulations to obtain statistically accurate and reliable state representations in dynamical systems. However, it is…

Numerical Analysis · Mathematics 2024-03-07 Tongtong Li , Anne Gelb , Yoonsang Lee

The ensemble Kalman filter (EnKF) is a method for combining a dynamical model with data in a sequential fashion. Despite its widespread use, there has been little analysis of its theoretical properties. Many of the algorithmic innovations…

Probability · Mathematics 2015-06-17 D. T. B. Kelly , K. J. H. Law , A. M. Stuart

We review the field of data assimilation (DA) from a Bayesian perspective and show that, in addition to its by now common application to state estimation, DA may be used for model selection. An important special case of the latter is the…

Applications · Statistics 2017-04-05 Alberto Carrassi , Marc Bocquet , Alexis Hannart , Michael Ghil

Accurate modeling and prediction of complex physical systems often rely on data assimilation techniques to correct errors inherent in model simulations. Traditional methods like the Ensemble Kalman Filter (EnKF) and its variants as well as…

Machine Learning · Computer Science 2024-09-12 Phillip Si , Peng Chen

Data assimilation techniques, such as ensemble Kalman filtering, have been shown to be a highly effective and efficient way to combine noisy data with a mathematical model to track and forecast dynamical systems. However, when dealing with…

Dynamical Systems · Mathematics 2023-05-17 Stephen A Falconer , David J. B. Lloyd , Naratip Santitissadeekorn