Hi folks,
I'm trying to do a set of simulations in CAM5, run in atmosphere-only mode (F_1850_CAM5 compset), that modifies the input emissions of DMS to reduce emissions in a specific region. I'm in search of information on the correct diagnostics for DMS and on how CAM5 handles DMS emissions so that I can interpret some of the results I'm seeing.
At the moment, I'm setting up my simulations to reduce DMS emissions in my region of interest by replacing the default DMS file in the below line of user_nl_cam with my own DMS emissions file:
srf_emis_specifier = 'DMS -> /data/carnegie/cesm-inputdata/atm/cam/chem/trop_mozart_aero/emis/aerocom_mam3_dms_surf_2000_c090129.nc',...
The model runs successfully. When I analyze the DMS_SRF and DMS variables output by the model, they show the signature of the emissions reduction I've specified in the region desired. However, it also shows an increase in DMS concentrations everywhere outside that region.
I've confirmed that it's not an issue with my input file, so now I'm trying to understand how the DMS_SRF and DMS output variables in the model are constructed and whether they're the correct variables to be looking at to assess the change in aerosol burden from the change in DMS emissions that I've imposed.
Does the model have some sort of compensation hardcoded through which a reduction in DMS emissions in one area will result in an increase everywhere else?
Is there some other emission specifier flag I should be using in user_nl_cam or another emissions input file that influences the amount of DMS the model produces?
Am I looking at the wrong diagnostics?
I've struck out on finding thorough documentation of the DMS treatment and diagnostics in CAM5, so if anyone has references or docs they can point me to that would be greatly appreciated!
Thanks,
Geeta
I'm trying to do a set of simulations in CAM5, run in atmosphere-only mode (F_1850_CAM5 compset), that modifies the input emissions of DMS to reduce emissions in a specific region. I'm in search of information on the correct diagnostics for DMS and on how CAM5 handles DMS emissions so that I can interpret some of the results I'm seeing.
At the moment, I'm setting up my simulations to reduce DMS emissions in my region of interest by replacing the default DMS file in the below line of user_nl_cam with my own DMS emissions file:
srf_emis_specifier = 'DMS -> /data/carnegie/cesm-inputdata/atm/cam/chem/trop_mozart_aero/emis/aerocom_mam3_dms_surf_2000_c090129.nc',...
The model runs successfully. When I analyze the DMS_SRF and DMS variables output by the model, they show the signature of the emissions reduction I've specified in the region desired. However, it also shows an increase in DMS concentrations everywhere outside that region.
I've confirmed that it's not an issue with my input file, so now I'm trying to understand how the DMS_SRF and DMS output variables in the model are constructed and whether they're the correct variables to be looking at to assess the change in aerosol burden from the change in DMS emissions that I've imposed.
Does the model have some sort of compensation hardcoded through which a reduction in DMS emissions in one area will result in an increase everywhere else?
Is there some other emission specifier flag I should be using in user_nl_cam or another emissions input file that influences the amount of DMS the model produces?
Am I looking at the wrong diagnostics?
I've struck out on finding thorough documentation of the DMS treatment and diagnostics in CAM5, so if anyone has references or docs they can point me to that would be greatly appreciated!
Thanks,
Geeta