Fix emissions in the user_cam_in

[yuqiang_zhang@duke_edu]

I'm running FCSD using a resolution of f09_f09_mg17.

Originally I ran the simulations for 20 yrs with the right date emissions inside. Now I want to fix anthropogenic or biomass burning emission in one specific year (See the year 1995). I changed to the following lines below:

"srf_emis_cycle_yr = 1995
srf_emis_type = 'CYCLICAL'"

The model gave me errors that

"ERROR:
open_trc_datafile: cycle year not found /work/08099/tg873981/stampede2/CESM2.1.2
/inputdata/atm/cam/chem/emis/CMIP6_emissions_1750_2015/emissions-cmip6_SO2_con tvolcano_vertical_850-5000_0.9x1.25_c20170724.nc"

Question 1:
So it looks like the model can not read the right volcano emissions. So in this case, how should I set up my model, without by creating new emissions datasets that assign the emissions in 1995 to all the other years?

Question 2:
A related question: how should I set up the model if I want to fix anthropogenic emission to specific year but the biomass burning emissions vary each other?

Thanks!

 

[rrbuchholz]

Answer 1: If you filedump the volcano emissions file you will see there are no emissions for 1995. The reason it works in a serial simulations is because CESM has the following namelist option for serial runs:
ext_frc_type = 'INTERP_MISSING_MONTHS'
The volcano emissions file does have 2000 and 2005 emissions, so you could choose one of those years instead for your cyclic run, or you will need to create or find emissions for volcanoes in 1995. As a first approximation, you could copy the 2000 emissions into a new file and rename the dates to 1995 if you want the other emissions (anth, fire etc) to be cyclic at 1995.

Answer 2: There is not internal option in CESM to set one of the emission type to constant and have the other emissions vary year to year. You will need to create repeated emissions files that have the same emissions for different years.

Hope that helps!