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Can WACCM use CO2 surface emission?

I notice WACCM and CAM-Chem use Lower Boundary Conditions (LBC) concentrations to drive long-lived spices like CO2. But is there a way to direct use CO2 surface emission fluxes like those BPRP component sets?

I tried to turn on co2_flag and co2flux_fuel_file brutally in the namelist, but it doesn't work



Benjamin Gaubert
New Member
Dear Yuan,
Note that for running with no prescribed Lower Boundary Conditions (LBC) concentrations,
you need to remove CO2 from the list [ foreach my $ghg ('CO2','CH4', 'N2O','CFC11','CFC12') ] in components/cam/bld/build-namelist

Look for the following paragraph:

# Make sure the flbc_list specifies all the GHGs needed for radiation.
my $flbc_list = $nl->get_value('flbc_list');
if (defined $flbc_list) {
# If flbc_list has already been defined, check that it contains all
# the GHGs needed by the radiation code.
foreach my $ghg ('CO2','CH4', 'N2O','CFC11','CFC12') {
if ($flbc_list !~ /$ghg/) {
die "$ProgName - ERROR: $ghg is missing from flbc_list \n";
else {
my $val = "'CO2','CH4','N2O','CFC11','CFC12'";
add_default($nl, 'flbc_list', 'val'=>$val);

I have run CAM-chem with prescribed fluxes of CO2 and CH4, but I am not familiar with the BPRP component sets.