level 2 flags

[angela.marinoni]

Hello,

when flagging the lev 2 data (horly average), should we report a specific flag that is present in lev 1 data only for a single sample (1 minute)?
Example: relative humidity >40% (flag 640) only during few minutes in the full hour.

Many thanks for your help
Best Regards

Angela

[jpp]

Hi Angela,

I was wondering as well...
... and then I decided to flag the hourly data according to the hourly average (for RH and below detection limit).
For flag 559 (local contamination), I use a formula to assess if local contamination affected significantly the hourly average.

Still I agree that we should have a common rule on this.

Ciao,

jp

[angela.marinoni]

Thanks Jean-Philippe!

Good idea the formula for local contamination.
Concerning the RH (flag 640), we decided to flag 640 the hourly average only if there are RH flags during at least 50% of the original data.

Cheers
Angela

[mfiebig]

Dear colleagues,

when averaging data, e.g. to hourly values, the guideline is that any informative flag, i.e. a flag that doesn't invalidate the line of data, that occurs during the averaging period, is copied to the average, even if it occurs only once. I agree that this rule is missing in the QC guidelines, and should be added there. We discussed this when writing the QC guidelines, and concluded that any other approach would leave too much room for interpretation.

Regards,
Markus

[angela.marinoni]

Thanks Markus,

we'll procced according your instruction.

Best