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arXiv · 2202.02862

Asymptotic behavior of the forecast-assimilation process with unstable dynamics

Dan Crisan·Michael Ghil
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Abstract

Extensive numerical evidence shows that the assimilation of observations has a stabilizing effect on unstable dynamics, in numerical weather prediction and elsewhere. In this paper, we apply mathematically rigorous methods to showing why this is so. Our stabilization results do not assume a full set of observations and we provide examples where it suffices to observe the model's unstable degrees of freedom.

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Dan Crisan, Michael Ghil. 2022-02-06. Asymptotic behavior of the forecast-assimilation process with unstable dynamics. https://doi.org/10.1063/5.0105590

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