activity
20192024
most citedCombining data assimilation and machine learning to emulate a dynamical model from sparse and noisy observations: a case study with the Lorenz 96 model

206 citations · 594 across the 12 of their papers we have counts for

collaborators

12 papers

cs.LG2024★ 1 cited

Towards diffusion models for large-scale sea-ice modelling

Tobias Sebastian Finn, Charlotte Durand, Alban Farchi +2

We make the first steps towards diffusion models for unconditional generation of multivariate and Arctic-wide sea-ice states. While targeting to reduce the computational costs by d…

physics.comp-ph2023★ 3 cited

Parameter sensitivity analysis of a sea ice melt pond parametrisation and its emulation using neural networks

Simon Driscoll, Alberto Carrassi, Julien Brajard +3

Accurate simulation of sea ice is critical for predictions of future Arctic sea ice loss, looming climate change impacts, and more. A key feature in Arctic sea ice is the formation…

cs.LG2023★ 13 cited

Machine learning with data assimilation and uncertainty quantification for dynamical systems: a review

Sibo Cheng, Cesar Quilodran-Casas, Said Ouala +14

Data Assimilation (DA) and Uncertainty quantification (UQ) are extensively used in analysing and reducing error propagation in high-dimensional spatial-temporal dynamics. Typical a…

cs.LG2022

Learning 4DVAR inversion directly from observations

Arthur Filoche, Julien Brajard, Anastase Charantonis +1

Variational data assimilation and deep learning share many algorithmic aspects in common. While the former focuses on system state estimation, the latter provides great inductive b…

physics.ao-ph2021★ 44 cited

Super-resolution data assimilation

Sébastien Barthélémy, Julien Brajard, Laurent Bertino +1

Increasing the resolution of a model can improve the performance of a data assimilation system: first because model field are in better agreement with high resolution observations,…

physics.ao-ph2021★ 166 cited

Bridging observation, theory and numerical simulation of the ocean using Machine Learning

Maike Sonnewald, Redouane Lguensat, Daniel C. Jones +3

Progress within physical oceanography has been concurrent with the increasing sophistication of tools available for its study. The incorporation of machine learning (ML) techniques…

eess.SP2021

Fusion of rain radar images and wind forecasts in a deep learning model applied to rain nowcasting

Vincent Bouget, Dominique Béréziat, Julien Brajard +2

Short- or mid-term rainfall forecasting is a major task with several environmental applications such as agricultural management or flood risk monitoring. Existing data-driven appro…

physics.comp-ph2020★ 10 cited

Combining data assimilation and machine learning to infer unresolved scale parametrisation

Julien Brajard, Alberto Carrassi, Marc Bocquet +1

In recent years, machine learning (ML) has been proposed to devise data-driven parametrisations of unresolved processes in dynamical numerical models. In most cases, the ML trainin…

stat.ML2020★ 99 cited

Bayesian inference of chaotic dynamics by merging data assimilation, machine learning and expectation-maximization

Marc Bocquet, Julien Brajard, Alberto Carrassi +1

The reconstruction from observations of high-dimensional chaotic dynamics such as geophysical flows is hampered by (i) the partial and noisy observations that can realistically be…

stat.ML2020★ 206 cited

Combining data assimilation and machine learning to emulate a dynamical model from sparse and noisy observations: a case study with the Lorenz 96 model

Julien Brajard, Alberto Carassi, Marc Bocquet +1

A novel method, based on the combination of data assimilation and machine learning is introduced. The new hybrid approach is designed for a two-fold scope: (i) emulating hidden, po…

physics.data-an2019★ 2 cited

Representing ill-known parts of a numerical model using a machine learning approach

Julien Brajard, Anastase Charantonis, Jérôme Sirven

In numerical modeling of the Earth System, many processes remain unknown or ill represented (let us quote sub-grid processes, the dependence to unknown latent variables or the non-…

eess.SY2019★ 50 cited

Learning Dynamical Systems from Partial Observations

Ibrahim Ayed, Emmanuel de Bézenac, Arthur Pajot +2

We consider the problem of forecasting complex, nonlinear space-time processes when observations provide only partial information of on the system's state. We propose a natural dat…