no code implementations • 4 Sep 2021 • Sébastien Barthélémy, Julien Brajard, Laurent Bertino, François Counillon
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, then the corrections are better sustained and, with ensemble data assimilation, the forecast error covariances are improved.
no code implementations • 9 Sep 2020 • Julien Brajard, Alberto Carrassi, Marc Bocquet, Laurent Bertino
Moreover, the attractor of the system is significantly better represented by the hybrid model than by the truncated model.
no code implementations • 17 Jan 2020 • Marc Bocquet, Julien Brajard, Alberto Carrassi, Laurent Bertino
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 obtained, (ii) the need to learn from long time series of data, and (iii) the unstable nature of the dynamics.
no code implementations • 6 Jan 2020 • Julien Brajard, Alberto Carassi, Marc Bocquet, Laurent Bertino
The output analysis is spatially complete and is used as a training set by the neural network to update the surrogate model.