Update to CMIP7 LULCC forcings

[wwieder]

It looks like a preliminary dataset for LULCC is available for CMIP7 (scroll down the table with links)

Specifically, is the v3.0 dataset any different that what we're already using from TRENDY? This github page could be helpful for tracking changes / updates to the dataset.

If this dataset is different from TRENDY, we should migrate to the latest v3 data so we're testing the model with LULCC data that's hopefully consistent with the final CMIP7 data.

@lawrencepj1 can you have a look at this dataset to see if it's different that what we've already integrated into the 5.3 tag?

Definition of Done:

• [x] @ekluzek create the alpha-ctsm5.4.CMIP7 branch and get it setup
• [x] @lawrencepj1 processes the new CMIP7 data
• [x] @lawrencepj1 does his verification of the new raw datasets
• [x] @olyson processes urban with Peter's new raw datasets
• [x] @wwieder creates f09, ne30 datasets with above
• [ ] @ekluzek figure out a process for verification of the new datasets
• [x] Verify the f09 and ne30 datasets
• [x] @olyson Run simulations with the new datasets at f09 and ne30
• [x] Verify based on the output that things are reasonable @olyson @wwieder
• [x] Move new raw data to /inputdata (their permanent location) (SSP raw data not available, yet)
• [x] @slevis-lmwg opens PR to add the new datasets into the XML in the alpha branch (alpha-ctsm5.4.CMIP7)
• [ ] Testing of mksurfdata_esmf with the new datasets (for the "subset" part of make all to work, need the fix in #3259)
• [ ] Create new datasets for all resolutions (check #2785)
• [ ] Verification of the new datasets
• [ ] Fix IC files for the new datasets
• [ ] Run testing with the new datasets, get it all working, including correct paths as per #3031
• [ ] rimport the raw data
• [ ] rimport the new surface datasets

[samsrabin]

See also: This brief slide deck with some info from Louise Chini; there's also a recording of her talk here.

[wwieder]

And this note from @ckoven on the FATES side

[lawrencepj1]

Hi Everyone Just for reference this is actually "CMIP6Plus" based on the CMIP Forcings meeting this morning. It is a test version that will be updated if needed to CMIP7 in 2025.

https://wcrp-cmip.org/wp-content/uploads/2024/10/2024-10-29_Forcings-drop-in_session.pdf

That said I am very happy to start going through the LUH3 data and getting CTSM53 raw PFT data generated from the new data. Thanks Peter

[olyson]

Since we now have dynamic urban capability, I wonder if we should include urban in this version. I'm not sure what was done with urban previously in CMIP6, maybe it was assigned to some other landunit?

[lawrencepj1]

Hi @olyson

Urban is transient in the LUH data and the values from LUH are explicitly put into the raw CLM5 and CTSM53 PFT data. Mksurfdata however does not use the raw PCT_URBAN data. There is a lot more information required for CTSM than provided by LUH so it would not be useful as a source for final surface or landuse timeseries data.

Cheers Peter

[olyson]

Thanks @lawrencepj1 . I was thinking that a simple and reasonable thing to do would be to use the PCT_URBAN supplied by LUH and assign it to a single density type (medium density, as that is by far the most common) and then simply splice in the static-in-time urban properties, which don't depend on PCT_URBAN and just depend on density type and region, into those files. We would end up with raw files that have the same information in them as we do now. If you have a sample raw CLM5/CTSM53 file, I could experiment with that.

[lawrencepj1]

Hi @olyson

Yes not a problem at all. You can find the latest TRENDY and LUH derived CTSM53 raw data at:

/glade/campaign/cesm/development/lmwg/landuse_source_data/CTSM53RawData

SSP5-8.5 has the largest urban expansion of the future scenarios. Here is 2015 vs 2100 values from these two raw files:

globalctsm53TRSSP585Deg025_240728/mksrf_landuse_ctsm53_TRSSP585_2015.c240728.nc globalctsm53TRSSP585Deg025_240728/mksrf_landuse_ctsm53_TRSSP585_2100.c240728.nc

Peter

[olyson]

Thanks @lawrencepj1 !

[wwieder]

At the SE meeting we noted this is something we want to be able to test, but not prioritize into CTSM dev at this stage

[lawrencepj1]

Meeting with @slevis-lmwg @ekluzek @mvdebolskiy:

Issues for discussion on CMIP6+ land use processing.

1. LUH3 has Plantation Forests. Do we want to process these explicitly or include them as Secondary Forests
2. Pre 1850 potential vegetation assumptions. These need to be clarified to include natural disturbance so we don't over specify forests in a natural world.

[slevis-lmwg]

1. LUH3 has Plantation Forests. Do we want to process these explicitly or include them as Secondary Forests

My gut response (that I shared with Peter) is to treat them as Secondary Forests for now, since the mksurfdata tool and the model can handle that without code changes.

[wwieder]

I think @slevis-lmwg's suggestion on plantation forests makes sense (include them as secondary forests).

I don't really know what do think about the potential veg question. Is this something that would be helpful to discuss in a targeted meeting, or the CLM science time slot on a Thursday?

How critical is it that we figure out a plan for potential veg for ongoing coupled model testing?

[ekluzek]

Thanks @lawrencepj1 @slevis-lmwg and @wwieder for the discussion.

I agree with everyone we certainly shouldn't add plantation forests in the model now. I will create an issue for us doing that in the future though.

@wwieder and @lawrencepj1 the importance of Potential vegetation is for the no-Anthro Paleo setup. This isn't immediately required for CESM work, but not something that can be neglected either -- at least for too-long. So in the next couple of weeks it would be OK, to wait on it. But, we'll want it in place fairly soon after that. So if there are scientific discussions to have on it -- I think they can wait a bit.

[ekluzek]

OK, I created a science discussion for this here:

https://github.com/ESCOMP/CTSM/discussions/3045

and an issue about potential veg in #3046

[lawrencepj1]

Thanks @ekluzek

Yes we already represent the added trees and will now add plantations as secondary forest. The potential vegetation will be produced as another set of data along with the historical and SSP data

---

From Peter's email:

The CMIP7 LUH3 data has been processed and the raw PFT data is available on the glade file system for the years 1700 - 2023. I wanted to check through to make sure it was correct before passing this on. Will is going to process the last step to generate the surface and landuse timeseries files for CTSM and CESM.

/glade/campaign/cesm/development/lmwg/landuse_source_data/CTSM53CMIP7RawData/globalctsm53histCMIP7Deg025_250417

with new LAI and soil color data in

/glade/campaign/cesm/development/lmwg/landuse_source_data/CTSM53CMIP7RawData/globalctsm53histMKSRFDeg025_250417

[olyson]

I've generated a set (1700-2023) of raw urban datasets for input to mksurfdata_esmf here:

/glade/campaign/cgd/tss/people/oleson/Dynamic_Urban_Data/CMIP7

e.g.,

urban_properties_CMIP7_ThreeClass_2023_c250417.nc

Below is a timeseries plot of the resulting density types:

[lawrencepj1]

Thanks Keith @olyson

This looks consistent with the LUH3 data and my guess is there is TBD in that flat line just not enough to see compared to the high and medium density urban areas.

Looking forward to seeing how this all works in CTSM53 (54?).

Peter

[olyson]

Thanks @lawrencepj1 . Yes, TBD is non-zero, just doesn't show up on this scale. It's about 550 km2 globally in 2023. There are some very small TBD areas in the 1700s and 1800s, which is probably not realistic since the first skyscrapers weren't built until the 1880s. But we have a minimum urban percentage in mksurfdata_esmf, so I'm expecting those TBD areas to not show up in the surface dataset. However, we may need to adjust that minimum to avoid completely zeroing out urban areas in the 1700s and 1800s. I think the next step in this process is to generate an f09 surface dataset that we can look at and verify. So some adjustments can be made then.

[olyson]

Referencing discussion here https://github.com/ESCOMP/CTSM/pull/3083 :

I've made the change to TBD and generated a new set of raw urban files, looks good. They are in the same location with a date of 250423, e.g.,

/glade/campaign/cgd/tss/people/oleson/Dynamic_Urban_Data/CMIP7/urban_properties_CMIP7_ThreeClass_2023_c250423.nc

[slevis-lmwg]

So far I have copied (not ./rimport-ed)

/globalctsm53histCMIP7Deg025_250417  
/globalctsm53histMKSRFDeg025_250417  
urban_properties_CMIP7_ThreeClass_1850_c250423.nc

to /glade/campaign/cesm/cesmdata/cseg/inputdata/lnd/clm2/rawdata/CTSM54RawData

@lawrencepj1 @olyson @wwieder pls let me know if there are files that I missed.

[slevis-lmwg]

From meeting with @olyson Need to get urban_properties_CMIP7... files for all the years (1700-2023) from the same directory where I found the 1850.

[wwieder]

Hey @lawrencepj1 I think there was an email about this, but I wondered what the status of potential vegetation dataset for the 5.4 tag is?

[lawrencepj1]

Sorry @wwieder @ekluzek @slevis-lmwg

Yes I had committed to get these processed last week. Thanks for the reminder. Will get on to it today and let you know when they are available.

Cheers Peter

[wwieder]

Thanks, Peter.

[ekluzek]

Note, there is a repository here to keep track of scripts for processing CMIP7 data:

https://github.com/NCAR/CMIP7_inputdata_processing

[slevis-lmwg]

Blocked by #3528