Configuring a run with more aerosol diagnostics in (NorESM2)

In both the default CAM5-aerosol packages (MAM3,MAM7) and the Oslo-aerosol packages, the budget terms can be taken out using a variable in the namelist :

&phys_ctl_nl
history_aerosol = .true.
/

Two more diagnostics are useful:

Enable estimates multiple calls to radiation which are necessary for effective radiative forcing estimates

Enable diagnostics for AEROCOM

To enable this, take the file cam/src/physics/cam_oslo$ vim preprocessorDefinitions.h and copy it to your SourceMods/src.cam folder

Change both preprocessor definitions to true

#define AEROCOM
#define AEROFFL

The AEROCOM-token turns on diagnostics needed for AEROCOM The AEROFFL-token tells the model to do additional radiation-diagnostics for aerosol indirect effect

Fields produced in monthly average files when running with budgets activated

Running with budgets activated will produce the following terms in the monthly output files:

Output variable name	Meaning	Comment
SF{Tracer}	Emissions from surface
GS_{Tracer}	gas phase chemistry	3D-emissions and gas phase washout included in this term
AQ_{Tracer}	aquous chemistry
{Tracer}_Mixnuc1	Activation in clouds and evaporation of cloud droplets
{Tracer}_DDF	Dry deposition flux (aerosol tracers)
{Tracer}_SFWET	Wet deposition flux (aerosol tracers)
{Tracer}_condtend	loss/production in condensation/nuclation	(CAM-Oslo only)
{Tracer}_coagTend	loss/production in coagulation	(CAM-Oslo only)
DF_{Tracer}	dry deposition flux (gas tracers)	output with history_aerosol with CAM-Oslo only
WD_A_{Tracer}	wet deposititon flux (gas tracers)	output with history_aerosol with CAM-Oslo only
Tracer_{CLXF}	3D-emissions (“external forcing”)	output with history_aerosol with CAM-Oslo only

Note: Since 3D-emissions and and gas washout rates are included in the term GS_{Tracer} in the mozart chemistry solver, the individual terms can be found like this (example for SO2):

ncap2 -O -s GS_ONLY_SO2=GS_SO2-WD_A_SO2-SO2_CLXF infile.nc outfile.nc

More info on SO2 budgets:

GS_SO2 contains the SO2 budget terms for all that goes on in the chemistry-routine, which is

1) Gas phase chemistry, 2) Wet deposition, and 3) 3D-emissions.

Gas phase chemistry is both production from DMS (GS_DMS) and loss through OH (GL_OH)

For calculations of net loss, e.g. used to calculate SO2 life-times, we're interested in the

loss through OH from the chemistry-term (GL_OH).

GS_SO2 = GL_OH + SO2_CLXF - WD_A_SO2 - GS_DMS*64/62

or

GL_OH = GS_SO2 - SO2_CLXF + WD_A_SO2 + GS_DMS*64/62

Estimating chemical loss w.r.t. S (instead of SO2 or DMS), for comparison with CAM4-Oslo numbers:

net chemial loss gas phase = (GS_SO2/1.998 - SO2_CLXF + WD_A_SO2)/1.998 + GS_DMS/1.938

net chemical loss = net chemial loss gas phase + AQ_SO2/1.998

Finally, total net loss (used to calculate life-time = -load/(net loss), where load = cb_SO2/1.998):

net loss =

- WD_A_SO2/1.998 ;wet deposition in kg/m2/sec (positive in output file)

- DF_SO2/1.998 ;dry deposition in kg/m2/sec (positive in output file)

+ AQ_SO2/1.998 ;wet phase production of SO4 in kg/m2/ses (negative in output file)

+ (GS_SO2 - SO2_CLXF + WD_A_SO2)/1.998 + GS_DMS/1.938 ; net chemical loss gas phase

Looking at the aerosol budgets (CAM-Oslo only)

Go to the directory models/atm/cam/tools/diagnostics/ncl/budgets

Change the filename to use in the file budgets.ncl (“myFileName” around line 18). Should be for example yearly average of month-avg file in a run with budgets

Run the script budgets.sh to create a pdf-file (output.pdf)

Preparing output for AEROCOM

To prepare output for aerocom, use the script located at models/atm/cam/tools/aerocom/ in the svn repository.

The script requires <ModelName>_<ExperimentName> and <Period> as input.

The script creates files named like

“aerocom3_<ModelName>_<ExperimentName>_<VariableName>_<VerticalCoordinateType>_<Period>_<Frequency>.nc”

<ModelName> ⇒ eg NorESM-CAM53
<ExperimentName> ⇒ svn{RevisionNumber}_YYMMDD{initials}_Freetext
<VariableName> ⇒ aerocom variable names
<VerticalCoordinateType> ⇒ “Surface”, “Column”, “ModelLevel”, “SurfaceAtStations”, “ModelLevelAtStations”
<Period> ⇒ eg “2008”, “2010”, “9999”
<Frequency> ⇒ “timeinvariant”,”hourly”, “daily”, “monthly”, “sat1000”, “sat1330”, “sat2200”, “sat0130”

Note that VerticalCoordinateType is dependent on the variable!! It is not a question about “vertical coordinate type used in model simulations”!

The script copies files on norstore into /projects/NS2345K/CAM-Oslo/DO_AEROCOM/<ModelName>_<ExperimentName>/renamed/