Track ‘n’ Type: Do tracked clouds show a realistic behavior with respect to cloud type?

The temporal development of cloud properties along the trajectory of a tracked clouds can show a behavior that is clearly unrealistic. For instance, a low-level cloud that is partly obscured by faint high-level clouds above can show development of cloud-top temperature with jumps of 40 K or more. To assess the general development of clouds tracked over central Europe, we have applied the ISCCP cloud classification to those clouds. It is found that the majority of the tracked clouds shows transitions between time steps that are either between identical cloud types (e.g. cumulus to cumulus) or represent reasonable development (e.g. stratus to stratocumulus or vice versa). The additional consideration of objective weather types enables an assessment of the large-scale conditions under which different cloud types are most abundant.