Short Report – QA/QC Meeting Mar 2020

02 Apr, 2020 QA/QC Short Report 7

Meeting Date: 2 Apr 2020

Participants

LH, SG, TB, MG, RM, IF, AS (7)

Info

If you are (Tech-)SRP, please attend QA/QC meetings or tell LH if you can’t, needed for planning of the meetings.
SRP & Tech-SRP: please prepare short statement about your site and send to to LH (max. 2 sentences)
The purpose of QA/QC meetings is to check on current, incoming data. SRPs choose specific issues we should look at together and discuss in the group. Fluxes are checked if the respective SRP wishes to do so.

Talking Points

Checking fluxes H2O, CO2, CH4, N2O

N2O flux spectral correction factor (LGR) @ CH-OE2, CH-INO

LH: Here is more info about the spectral correction factor (scf)
I just checked the plot for the latest CH-INO output (N2O fluxes, LGR), and as I suspected the scf was indeed veeeeeeeeeeeery high, which means the spectral correction did not work. Here is the plot:

You can see that the scf is > 10, which means that the fluxes are approx. 10 times larger than they should be. Typically, the scf is in the range between 1 and 2, most of the time it should be approx. 1.3. In this case there are times where the scf is 50(!), which is of course far to high. This is an error in EddyPro and was solved in a newer version > 7.0.4.

N2O mixing ratio (QCL) @CH-CHA

As an add on to the mixing ratio discussion: During clear nights and distinct diurnal cycles (for air temperature in green) the N2O is building up in the nighttime stable boundary layer (here in ppb, blue). At sunrise the air is mixed and the concentration decreases again.