Requested output flags

[jonas-witthuhn]

Some additional, helpful flags/variables:

• number_cloud_layers (time): Tells how much cloud layers are detected at a specific time-step
• flag_virga_at_timestep (time): Tells if there is virga/precip in any layer at a specific time-step
• flag_virga_at_timestep_layer (time, layer): Tells if there is virga/precip in a specific layer at a specific time-step

[jonas-witthuhn]

Some clarification might be needed: It is totally possible, that there is a value of cloud-base height in the output data, but, at the same time, there is no cloud detected. This can occur frequently in the lowest level, when the cloud-base height is filled with the LCL, but also in upper levels due to filling of gaps or when the ceilometer sees some cloud-base, but the particles are to small to be seen with the radar. We could restrict the cloud-base to time-steps when a cloud or virga is actually detected, but the issue will persist in situations when there is virga (e.g. fall streaks) but no cloud above.

In addition to the additional flags on top, maybe add:

• flag_cloud_at_timestep / flag_cloud_at_timestep_layer
• add note to the cloud-base variable

[jonas-witthuhn]

All requested flags have been added