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. ${\textstyle {\frac {3}{5}}\cdot }$dtime${\textstyle _{oper}}$).
ndyn_substeps	-	run_nml	There is no need to call the dynamics more often than in operational setup. Adjust it according to your dtime choice.
inwp_gscp	6	nwp_phy_nml	In order to enable aerosol-cloud-interactions within ICON-ART, you have to specify this. Note, that you will still need to set iart_aci_warm and iart_aci_cold from .
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
Atmospheric Aerosol
lart_aerosol	Main switch for the treatment of atmospheric aerosol
iart_seasalt	Treatment of sea salt aerosol
iart_dust	Treatment of mineral dust aerosol
iart_anthro	Treatment of anthropogenic aerosol
iart_fire	Treatment of wildfire aerosol
iart_volcano	Treatment of volcanic ash aerosol
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