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Related papers: A variational approach to Data Assimilation in the…

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We consider a recently introduced continuous data assimilation (CDA) approach for downscaling a coarse resolution configuration of the 2D Benard convection equations into a finer grid. In this CDA, a nudging term, estimated as the misfit…

Optimization and Control · Mathematics 2015-12-22 M. U. Altaf , E. S. Titi , O. M. Knio , L. Zhao , M. F. McCabe , I. Hoteit

This paper studies the role of sparse regularization in a properly chosen basis for variational data assimilation (VDA) problems. Specifically, it focuses on data assimilation of noisy and down-sampled observations while the state variable…

Data Analysis, Statistics and Probability · Physics 2014-06-25 A. M. Ebtehaj , M. Zupanski , G. Lerman , E. Foufoula-Georgiou

4D-variational data assimilation is applied to the Lorenz '63 model to introduce a new method for parameter estimation in chaotic climate models. The approach aims to optimise an Earth system model (ESM), for which no adjoint exists, by…

Atmospheric and Oceanic Physics · Physics 2025-04-18 Philip David Kennedy , Abhirup Banerjee , Armin Köhl , Detlef Stammer

A Martian semiannual oscillation (SAO), similar to that in the Earth's tropical stratosphere, is evident in the Mars Analysis Correction Data Assimilation reanalysis dataset (MACDA) version 1.0, not only in the tropics, but also extending…

Earth and Planetary Astrophysics · Physics 2019-07-17 Tao Ruan , Neil T. Lewis , Stephen R. Lewis , Luca Montabone , Peter L. Read

Data assimilation (DA) combines partial observations with dynamical models to improve state estimation. Filter-based DA uses only past and present data and is the prerequisite for real-time forecasts. Smoother-based DA exploits both past…

Systems and Control · Electrical Eng. & Systems 2026-01-21 Marios Andreou , Nan Chen , Yingda Li

This paper presents a reduced-order approach for four-dimensional variational data assimilation, based on a prior EO F analysis of a model trajectory. This method implies two main advantages: a natural model-based definition of a mul…

A method of data assimilation (DA) is employed to estimate electrophysiological parameters of neurons simultaneously with their synaptic connectivity in a small model biological network. The DA procedure is cast as an optimization, with a…

Neurons and Cognition · Quantitative Biology 2020-02-05 Eve Armstrong

Variational data assimilation technique applied to identification of optimal approximations of derivatives near boundary is discussed in frames of one-dimensional wave equation. Simplicity of the equation and of its numerical scheme allows…

Mathematical Physics · Physics 2015-05-13 Eugene Kazantsev

Data assimilation (DA) is crucial for enhancing solutions to partial differential equations (PDEs), such as those in numerical weather prediction, by optimizing initial conditions using observational data. Variational DA methods are widely…

Machine Learning · Computer Science 2025-09-30 Hamidreza Moazzami , Asma Jamali , Nicholas Kevlahan , Rodrigo A. Vargas-Hernández

Astronomical data are typically irregular in time, e.g. the space (HIPPARCOS/TYCHO, KEPLER, GAIA, WISE etc.) and ground-based CCD (NSVS, ASAS, CRTS, SuperWASP etc.) and photographic (Harvard, Sonneberg, Odessa etc.) photometrical surveys.…

Solar and Stellar Astrophysics · Physics 2019-02-05 Ivan L. Andronov

This data assimilation study exploits infrasound from explosions to probe an atmospheric wind component from the ground up to stratospheric altitudes. Planned explosions of old ammunition in Finland generate transient infrasound waves that…

Atmospheric and Oceanic Physics · Physics 2020-04-28 Javier Amezcua , Sven Peter Näsholm , Erik Mårten Blixt , Andrew J. Charlton-Perez

With the recent interest in net-zero sustainability for commercial buildings, integration of photovoltaic (PV) assets becomes even more important. This integration remains a challenge due to high solar variability and uncertainty in the…

Systems and Control · Computer Science 2018-08-28 Chaitanya Poolla , Abraham K. Ishihara

Soil moisture conditions can influence the evolution of a tropical cyclone (TC) that is partially or completely over land. Hence, better constraining soil moisture initial conditions in a numerical weather prediction model can potentially…

Atmospheric and Oceanic Physics · Physics 2023-08-01 Jana Kolassa , Manisha Ganeshan , Erica McGrath-Spangler , Oreste Reale , Rolf Reichle , Sara Q. Zhang

This paper describes a flexible approach to short term prediction of meteorological variables. In particular, we focus on the prediction of the solar irradiance one hour ahead, a task that has high practical value when optimizing solar…

Neural and Evolutionary Computing · Computer Science 2019-11-06 Pierrick Bruneau , Philippe Pinheiro , Yoann Didry

Context. Recently our ability to study stars using asteroseismic techniques has increased dramatically, largely through the use of space based photometric observations. Work has also been done using ground based spectroscopic observations…

Solar and Stellar Astrophysics · Physics 2018-10-03 Jesper Schou

Accurate short-term wind speed forecasting is needed for the rapid development and efficient operation of wind energy resources. This is, however, a very challenging problem. Although on the large scale, the wind speed is related to…

Applications · Statistics 2014-12-08 Xinxin Zhu , Kenneth P. Bowman , Marc G. Genton

As the solar wind propagates through the heliosphere, dynamical processes irreversibly erase the signatures of the near-Sun heating and acceleration processes. The elemental fractionation of the solar wind should not change during transit…

Solar and Stellar Astrophysics · Physics 2020-08-11 D. Stansby , D. Baker , D. H. Brooks , C. J. Owen

Achieving sub-arcsecond co-registration across varying time-lines of multi-wavelength and instrument images is not trivial, and requires accurate characterization of instrument pointing jitter. In this work we have investigated internal…

Solar and Stellar Astrophysics · Physics 2015-01-22 N. Brice Orange , Hakeem M. Oluseyi , David L. Chesny , Maulik Patel , Patrick Champey , Katie Hesterly , Dylan Anthony , Robert Treen

The spatio-temporal interpolation of large geophysical datasets has historically been addressed by Optimal Interpolation (OI) and more sophisticated equation-based or data-driven Data Assimilation (DA) techniques. Recent advances in the…

Predictions of the solar wind at Earth are a central aspect of space weather prediction. The outcome of such a prediction, however, is highly sensitive to the method used for computing the magnetic field in the corona. We analyze the impact…

Solar and Stellar Astrophysics · Physics 2017-09-07 Marion Weinzierl , Francois-X. Bocquet , Anthony R. Yeates