In - depth analysis reveals that the model's
shallow cumulus convection scheme tends to significantly under - produce clouds during the times when shallow cumuli exist in the observations, while the deep convective and stratiform cloud schemes significantly over-produce low - level clouds throughout the day.
The links between model biases and the underlying assumptions of the
shallow cumulus scheme are further diagnosed with the aid of large - eddy simulations and aircraft measurements, and by suppressing the triggering of the deep
convection scheme.