New population dataset for streams files

[adrifoster]

TRENDY gave us a new population dataset (which is used in our fire models).

It's located /glade/derecho/scratch/afoster/TRENDY_2024/inputs/pop/population.nc right now. Compare to the default dataset we currently use which is /glade/campaign/cesm/cesmdata/inputdata/lnd/clm2/firedata/clmforc.Li_2017_HYDEv3.2_CMIP6_hdm_0.5x0.5_AVHRR_simyr1850-2016_c180202.nc

The old dataset only goes to 2016, whereas this new one goes out to 2023. Both are derived from HYDE. (HYDE 3.4 for the new one; HYDE 3.2 for our old one).

Should we update this at some point? @lifang0209 did you make this dataset?

@wwieder @lawrencepj1

[ekluzek]

In the CTSM SE meeting this morning we decided we would NOT bring this in for ctsm5.3.0 and likely not for this years TRENDY.

But, bringing this in as a ctsm6.0.0 type update would be a good thing to do. It won't change answers enough for it to be a problem to bring in alongside other tuning changes. There's not time to get it done for ctsm5.3.0.

[lifang0209]

@adrifoster It's important to extend the forcing data period to 2023 to correctly simulate the changes in human ignitions and suppression effects during 2016-2023. I have HYDE3.3. I could made new population density data for CLM6/CTSM6 based on HYDE3.4, but I cannot find it at the path you provided (/glade/derecho/scratch/afoster/TRENDY_2024/inputs/pop/population.nc).

[adrifoster]

@adrifoster It's important to extend the forcing data period to 2023 to correctly simulate the changes in human ignitions and suppression effects during 2016-2023. I have HYDE3.3. I could made new population density data for CLM6/CTSM6 based on HYDE3.4, but I cannot find it at the path you provided (/glade/derecho/scratch/afoster/TRENDY_2024/inputs/pop/population.nc).

Sorry @lifang0209 I moved it to /glade/campaign/cgd/tss/projects/TRENDY2024/inputs/pop/population.nc for long-term since it was in my scratch.

If you are able to update our population streams data that would be great!

[ekluzek]

This is something we need to do for CMIP7 simulations, so should do as part of the CTSM5.4 minor version update.

[lifang0209]

@ekluzek Hi Erik,
The global 0.5-degree annual population density dataset (1850-2023) derived from HYDE3.4 population data is at:
/glade/derecho/scratch/fangli/hdm1850-2023-FangLi-250211.nc

Data processing methods:
Temporal:
1850-1949: Linearly interpolated from HYDE3.4 decadal population data
1950-2023: Directly from HYDE3.4 annual population data
Spatial:
All data regridded from HYDE3.4 5-minute resolution to 0.5 degree
Then, I derived population density (variable: hdm) by dividing population data by land area

Fang

[wwieder]

Thanks for making this file available, Fang. Do you know how this may compare to data that will be used for CMIP7?

[lifang0209]

CMIP7 population density forcing data is currently unavailable and marked as unknown and TBD, see below