Preparing N-deposition input files for CMIP6 scenarios and historical runs

[jmaerz]

Hi @mvertens and @JorgSchwinger , I am about preparing the input files for the N-deposition for the historical and future period (SSPs). This means to combine the esgf input files in such a way that it can be used by iHAMOCC (+ regridding) - split into NOy and NHx. Afterward, I aim at cleaning up the nitrogen deposition reading code as suggested in #340. For now, I try to document the retrieval of data, merging of files and regridding as good as I can in my own folder, but it would be nice to discuss a more public location for such scripts and information (as suggested also in #376).

This issue will be limited to N-input files for extended nitrogen cycle runs with the MCT coupler, since with PR #410, the generation isn't further needed.

[jmaerz]

@JorgSchwinger , I prepared a script that more or less automatically prepares (most, currently the 2000 file is still to do) input files. I downloaded input files via the esgf metacenter: https://esgf-metagrid.cloud.dkrz.de/search , using their script preparation tool, launched their wget script with the option -s to not having to provide e.g. OpenID (just to document the steps taken).
When preparing the files for iHAMOCC (combining dry and wet NHx and NOy as input), I stumbled over a few things:

1. The downloaded files seem to partially only be from 01.2015-12.2099 (and not until 12.2100 as some of the already prepared files on betzy). How did you deal with this in the past?
2. The ndep_2000... files: Is this just the year 2000 from the historical time period that is written out as input file?
3. Which 0.125v4 grid to use for remapping?

[JorgSchwinger]

• The downloaded files seem to partially only be from 01.2015-12.2099 (and not until 12.2100 as some of the already prepared files on betzy). How did you deal with this in the past?

Just repeat the last year

• The ndep_2000... files: Is this just the year 2000 from the historical time period that is written out as input file?

Yes, I think so

• Which 0.125v4 grid to use for remapping?

@AleksiNummelin or @matsbn need to answer this (but this should actually be cleaned up such that there is only ONE 0.125v4 grid...)