Treating Nonlinearities in Data-Space Variational Assimilation - Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications - page 243

superior analysis circulation. This circulation is dynamically consistent for the
longer time window, avoiding the frequent discontinuities present in 3D-Var or short
window 4D-Var solutions. To achieve similar results, the overfitting methods would
require nearly error free observations at a frequency that approaches the time-step of
the model. For geophysical flows with temporally sparse data, properly constrained
data-space methods provide an ideal configuration for assimilation.
Acknowledgements The author would like to thank Dr. Bruce Cornuelle for his thoughts and
discussions. Dr. Powell was supported by the Office of Naval Research contract #N00014-09-
10939.
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