FRAM data: cloud generation and update

Following from issue #105, we will receive FRAM integrated aod values each minute (or each few minutes, but then they will be interpolated in time). Also, depending on the replies to the issue #105 questions, we will have a baseline aod value which will be either 0 or some positive number. Out of these, the following questions are arising.

• Cloud_gen_trigger = FRAM_aod - baseline_aod: what should be the value of Cloud_gen_trigger in order to start creating clouds? An indication here is the fact that we can have subvisible Cirrus clouds with an aod < 0.03. Lets try to concretise this value.
• What if Cloud_gen_trigger < 0 ?
• Cloud_upd_trigger = Fram_aod(t + δt) - Fram_aod(t): what's the minimum value of the cloud update trigger? Should be equal to the cloud generation trigger (makes some sense). Or shall we implement a first rudimentary uncertainty estimation?
• If the answer to the question above is to make some estimation of the systematics uncertainty due to the new sky state, is it CalibPipe which should do the task or SimPipe? SimPipe is already assigned with the task to estimate the systematics due to the sky state, however the question here is whether CalibPipe should provide a new sky state to SimPipe for each FRAM aod value (measured or interpolated).