47 citations · 86 across the 7 of their papers we have counts for
7 papers
The entropy rate of Linear Additive Markov Processes
Bridget Smart, Matthew Roughan, Lewis Mitchell
This work derives a theoretical value for the entropy of a Linear Additive Markov Process (LAMP), an expressive model able to generate sequences with a given autocorrelation struct…
A shadowing-based inflation scheme for ensemble data assimilation
Thomas Bellsky, Lewis Mitchell
Artificial ensemble inflation is a common technique in ensemble data assimilation, whereby the ensemble covariance is periodically increased in order to prevent deviation of the en…
Accounting for model error due to unresolved scales within ensemble Kalman filtering
Lewis Mitchell, Alberto Carrassi
We propose a method to account for model error due to unresolved scales in the context of the ensemble transform Kalman filter (ETKF). The approach extends to this class of algorit…
Non-global parameter estimation using local ensemble Kalman filtering
Thomas Bellsky, Jesse Berwald, Lewis Mitchell
We study parameter estimation for non-global parameters in a low-dimensional chaotic model using the local ensemble transform Kalman filter (LETKF). By modifying existing technique…
On finite-size Lyapunov exponents in multiscale systems
Lewis Mitchell, Georg A. Gottwald
We study the effect of regime switches on finite size Lyapunov exponents (FSLEs) in determining the error growth rates and predictability of multiscale systems. We consider a dynam…
Data assimilation in slow-fast systems using homogenized climate models
Lewis Mitchell, Georg A. Gottwald
A deterministic multiscale toy model is studied in which a chaotic fast subsystem triggers rare transitions between slow regimes, akin to weather or climate regimes. Using homogeni…
Controlling overestimation of error covariance in ensemble Kalman filters with sparse observations: A variance limiting Kalman filter
Georg A. Gottwald, Lewis Mitchell, Sebastian Reich
We consider the problem of an ensemble Kalman filter when only partial observations are available. In particular we consider the situation where the observational space consists of…