Namelist

Recommended ICON Namelist Settings

It is necessary for the user to choose the ICON settings carefully. Part of the values listed in are recommended to obtain a stable ICON-ART simulation with scientifically reasonable results. Another part is necessary to enable ART features like aerosol-cloud-interactions.

Recommended ICON namelist settings for ART tracers.

Parameter	Value	Namelist	Description
dtime	-	run_nml	If facing stability problems, it is recommended to use a shorter time step as recommended by operational setups (e.g. 0.5*dtime).
inwp_gscp	4	nwp_phy_nml	Standard value is 1. Set this to 4 for aerosol-cloud-interactions within ICON-ART. Note, that you will still need to set iart_aci_warm and iart_aci_cold < 0 .
irad_aero	6	radiation_nml	aerosol optical properties are taken from climatology
	9		optical properties depend on aerosol concentrations (set iart_ari = 1 in art_nml )

ART Namelists

ICON-ART has an own namelist to modify the setup of ART simulations at runtime. The main switch for ART, lart, is located inside run_nml. The namelist for the other ART switches is called art_nml.

A naming convention is used in order to show the type of data. An INTEGER namelist parameter starts with iart_, a REAL namelist parameter starts with rart_, a LOGICAL namelist parameter starts with lart_, and a CHARACTER namelist parameter starts with cart_.

The ICON-ART namelist is located in the module src/namelists/mo_art_nml.f90. General namelist parameters are listed and explained within . Namelist parameters for ART input are listed within . Namelist parameters related to atmospheric chemistry are listed within . Namelist parameters related to aerosol physics are listed within . Namelist parameters related to feedback processes between aerosols and meteorological variables are listed in . Finally, namelist parameters related to physics parameterizations in ICON are listed in.

Art namelist parameters

Name	function
General Variables
iart_init_aero	Initialization of aerosol species
iart_init_gas	Initialization of gaseous species
lart_diag_out	Enable output of diagnostic fields
lart_pntSrc	Enables point sources
lart_emiss_turbdiff	Switch if emissions should be included as surface flux condition
cart_input_folder	Absolute Path to ART Input Files
cart_io_suffix	user given suffix instead of automatically generated grid number
Atmospheric Chemistry
lart_chem	Main switch to enable chemistry
lart_chemtracer	Switch for parametrised chemtracers
lart_mecca	Switch for MECCA chemistry
lart_psc	Switch for computation of PSCs
cart_vortex_init_date	Date of vortex initialization
cheminit_file(max_dom)	Path to chemical initialization file
cart_cheminit_coord	Path to chemical initialization coordinate file
cart_cheminit_type	Type of chemical initialization coordinate file
XML configuration
cart_chemtracer_xml	Path to XML file for parametrised chemtracers
cart_mecca_xml	Path to XML file for MECCA tracers
cart_aerosol_xml	Path to XML file for aerosol tracers
cart_modes_xml	Path to XML file for modes
cart_pntSrc_xml	Path to XML file for point sources
cart_diagnostics_xml	Path to XML file for aerosol diagnostics
cart_emiss_xml_file	Path to XML file for emission metadata
cart_ext_data_xml	Path to XML file for metadata of datasets prescribing tracers
cart_coag_xml	Path to XML file for coagulation processes
Atmospheric Aerosol
lart_aerosol	Main switch for the treatment of atmospheric aerosol
iart_seasalt	Treatment of sea salt aerosol interaction with radiation
iart_dust	Treatment of mineral dust aerosol interaction with radiation
iart_anthro	Treatment of anthropogenic aerosol
iart_fire	Enables treatment of wildfire aerosol
iart_volcano	Enables treatment of volcanic ash aerosol
iart_isorropia	Treatment of aerosol gas partitioning
iart_nonsph	Treatment of nonspherical particles
iart_pollen	Treatment of pollen
iart_radioact	Treatment of radioactive particles
cart_volcano_file	Absolute path + filename of input file for volcanoes
cart_radioact_file	Absolute path + filename of input for radioactive emissions
Feedback Processes
iart_aci_warm	Nucleation of aerosol to cloud droplets
iart_aci_cold	Nucleation of aerosol to cloud ice
iart_ari	Direct interaction of aerosol with radiation

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	Name	Default Value	Description	Details	Dependencies
General Variables	iart_init_aero	0	Initialization of aerosol species.	0: Initialization with 0 1: At this point climatological aerosol profiles may be included as standard initialization 2: Initialization with fixed value different from 0.0_wp (e.g. using 10.0_wp) 5: Set aerosol tracer initial values from file 6: Read background climatology from aes-ham
	iart_init_gas	0	Initialization of gaseous species.	0: Nothing to do here, tracers are initialized with 0.0_wp automatically 1: At this point climatological gas profiles may be included as a standard initialization 4: Initializing chemical tracers using method given by .xml 5: Initializing from file
	lart_diag_out	.FALSE.	Enable output of diagnostic fields.	If this switch is set to .TRUE., diagnostic output fields are available. Set it to .FALSE. when facing memory problems.	cart_diagnostics_xml
	lart_pntSrc	.FALSE.	Enables addition of point sources for passive tracer.	The sources are controled via cart_pntSrc_xml.	cart_pntSrc_xml
	lart_emiss_turbdiff	.FALSE.	Switch if emissions should be included to the turbulence scheme as surface flux condition
	cart_input_folder	-	Absolute path where input folder of ART initialization and external files are located.
	cart_io_suffix	'grid-nr'	Specifies the grid specification in ART input file name convention. With default grid-number it is replaced by the four character string due to ICON parameter number_of_grid_used . Any other string can be included for each domain.
	iart_modeshift	1	Doing mode shift (only temporary switch for debug)	0 = off 1 = on
Atmospheric Chemistry	lart_chem	.FALSE.	Main switch to enable chemistry		lart_chemtracer = .TRUE. OR lart_mecca = .TRUE.
	lart_chemtracer	.FALSE.	Switch for chemical tracer processes		cart_chemtracer_xml
	lart_mecca	.FALSE.	Enables the computation of full chemistry via the MECCA package.		cart_mecca_xml
	lart_psc	.FALSE.	Switch if polar stratospheric clouds should be calculated
	cart_vortex_init_date	-	Date of vortex initialization
	cart_cheminit_file(max_dom)	-	Path to chemical initialization file
	cart_cheminit_coord	-	Path to chemical initialization coordinate file
	cart_cheminit_type	-	Type of chemical initialization coordinate file
XML configuration	cart_chemtracer_xml	-	Path to XML file for parametrised chemtracers
	cart_mecca_xml	-	Path to XML file for MECCA chemistry tracers
	cart_aerosol_xml	-	Path to XML file for aerosol tracers
	cart_modes_xml	-	Path to XML file for modes
	cart_pntSrc_xml	-	Path to XML file for point sources
	cart_diagnostics_xml	-	Path to XML file for aerosol diagnostics (GRIB2 meta data)
	cart_emiss_xml_file	-	Path and file name of the xml files for emission metadata
	cart_ext_data_xml	-	Path to XML file for metadata of datasets prescribing tracers
	cart_coag_xml	-	Path to XML file for coagulation processes
Atmospheric Aerosol	lart_aerosol	.FALSE.	Main switch for the treatment of atmospheric aerosol		cart_aerosol_xml
	iart_seasalt	0	Treatment of sea salt aerosol	0: No treatment. 1: Initialization of seasalt emission. Add 6 to iart_ntracer. 2: A second parameterization is used for the seasalt emission. Add 6 to iart_ntracer.
	iart_dust	0	Treatment of mineral dust aerosol	0: No treatment. 1: Initialization of mineral dust aerosol (Vogel et al. 2006). 2: Simplified version of emission fluxes of mineral dust aerosol (Vogel et al. 2006).
	iart_anthro	0	Treatment of anthropogenic aerosol	0: No treatment. 1: With the anthropogenic aerosol.
	iart_fire	0	Treatment of wildfire aerosol	0: Nothing to do, no biomass burning emissions 1: Initialization of biomass burning tracer data
	iart_volcano	0	Treatment of volcanic ash aerosol	0: No treatment. 1: 1-moment treatment. Add 6 to iart ntracer. 2: 2-moment treatment. Add 6 to iart_ntracer.
	iart_nonsph	0	Treatment of nonspherical particles	0: USE Mie values 1: Ellipsoid mixture
	iart_pollen	0	Treatment of pollen	0: No treatment 1: Initialization of pollen tracer data
	iart_radioact	0	Treatment of radioactive particles	0: No treatment. 1: As described in the ICON-ART technical documentation. An input file has to be specified via cart_radioact_file. Add 9 to iart_ntracer.
Feedback Processes	iart_aci_warm	0	Nucleation of aerosol to cloud droplets	0: Constant cloud droplet number inwp_gscp=4 1: Nucleation Warm ART
	iart_aci_cold	0	Nucleation of aerosol to cloud ice	0: Nucleation originial 2-moment scheme (1,2,3,4,5): Nucleation Cold ART 6: With tracking of activated dust 7: With prognostic dust as input and relaxation of activated dust
	iart_ari	0	Direct interaction of aerosol with radiation	0: No radiation feedback with ART aerosols 1: Turn on radiation feedback with ART aerosols (ASH or DUST). Set irad_aero = 9 in radiation_nml
Emissions	cart_volcano_file	-	Absolute path + filename of input file for volcanoes
	cart_radioact_file	-	Absolute path + filename of input for radioactive emissions
	Online emission module		See oem namelist