Comparisons of non-Gaussian with Gaussian based observational quality control measures and their impacts on data assimilation systems
With the recent derivation of a mixed-distribution based incremental VAR data assimilation system, the need to adapt the current Gaussian based quality control measures to allow for the correct assessment of lognormal distribution based observational errors has to be addressed. We present lognormal and mixed lognormal-Gaussian based versions of the buddy check, variational bias correction, and the gross error check and apply then for different observations of the Lorenz 1963 model and compare them to the Gaussian based versions. Finally, we assess what impacts the different quality control measures have on a mixed Gaussian-lognormal based static incremental 4DVAR data assimilation system with the Lorenz 1963 model.
Dr. Steven James Fletcher Colorado State University