MNH-V6-0-0

Release date : 19/03/2026

Note

Summary

  • Performance: MNH-V6-0-0 can be run on GPUs. The dynamics (advection schemes and pressure solvers), the microphysics ICE3 and the turbulence scheme are accelerated. The tested chips are NVIDIA GPUs V100/A100/H100, NVIDIA GH200 APUs, AMD GPUs MI250X and AMD APUs MI300A.

  • Input / Output

    • NetCDF compression is now enabled by default for all written netCDF files with the Zstandard library. Zstd is even faster than using no compression and reduces significantly the size of the netCDF files.

    • LFI: this file format is no longer supported for writing.

    • Coupling: HRRR-WRF (USA) and ICON (Europe and global) can be used as external file for realistic cases.

    • Diagnostics: online coarse-graining with multiple user defined sub-domains.

  • Physics parameterizations and dynamics

    • Default values are changed for ECRAD, turbulence, ICE3 and condensation schemes.

    • Radiation: ECRAD updated to 1.6.1 version and compiled by default. More than 50 new namelist options from ECRAD-offline are now available.

    • Wind turbine: code updated to EOL-2.0.1. It includes a new kinematic architecture with 6D harmonic floating motion, controller architecture including now TABLE, JONKM, and ROSCO methods and a 3D Gaussian smearing method.

    • Aerosol & Chemistry: new library ACLIB included. It wraps the original Méso-NH code and exposes interfaces to use the aerosols and chemistry codes of MOCAGE and ARPEGE-ALADIN-climat.

    • Turbulence: updated constants impacting all mixing lengths, new Goger term, dynamical and buoyancy TKE production from EDMF.

    • Shallow convection: new coefficients to tune the scheme, new type of env mixing for buoyancy sorting scheme, upward length to use in the dry detrainement and mixing of TKE by updrafts.

    • Microphysics LIMA: option to mimic the ICE3 scheme, new graupel processes options, PDF for subgrid precipitation, new prognostic up to 4 ice crystal shapes, self collection of ice crystals, init of CCN and IFN by ORILAM, interpolation of CAMS fields

    • Microphysics ICE3: new PDF used to diagnose autoconversion from the shallow convection cloud, Kogan autocoversion of liquid water

  • Cleaning & restructuration: src/LIB/SURCOUCHE is moved to MNH/io and MNH/parallel; new subdirectories in src/MNH; MY_RUN renamed in examples; overall cleaning of obsolete binaries and tools.

Running on GPUs

The 6.0.0 version of Meso-NH is the first official version supporting offloading computation to GPUs, with the use of the OpenACC API. For this first release, the schemes ported to GPUs are:

  • Advection (scalars and wind)

  • Turbulence (3D)

  • Cloud (ICE3)

  • Pressure solvers (Multi-Grid and FFT)

For developpment & modification done for GPUs port you could look at :

Two types of GPUs vendors are supported: Nvidia and AMD.

  • For Nvidia GPUs, the nvhpc compiler suite is used. It is free to download on the NVIDIA HPC SDK website. The code has been tested on different supercomputers (Jean-Zay, Belenos, Irene, Turpan, Nuwa, Romeo, Kairos) with different GPU types, such as V100, A100, H100 and GH200.

  • For AMD GPUs, due to the lack of a freely available and efficient Fortran compiler supporting OpenACC, the porting has been done with the proprietary HPE/Cray Fortran compiler. At the time being, it is only available in France on the Adastra supercomputer at CINES (LUMI in Finland or Frontier and El Capitan in the US could also be used). MI250X GPUs and MI300A APUs have been tested.

For the parts not ported to GPUs:

  • the user could use them: computations of parts not ported to GPUs will be executed on CPUs;

  • the results will be correct. They are bit-reproductible between CPU (with OPTLEVEL=OPENACCDEFONLY) and GPU runs. The memory transfers betwen CPUs and GPUs are automatically managed thanks to the managed memory (with OPTLEVEL=MANAGED) or unified memory (with OPTLEVEL=UNIFIED);

  • performance of the whole code will be lower. If useful or necessary, please contact the support team to initiate a collaboration to port it.

Note

There are limitations to the GPU version. These limitations are due to a lack of time to port these features, and not to a limitation of OpenACC. The main limitations are:

  • No grid-nesting

  • Only open boundaries

  • For the new Multi-Grid solver, the number of points in the horizontal directions must be a power of 2 (e.g. 128, 256, 512, etc.).

Default namelist changes

  • ECRAD: the shortwave and longwave solver was SPARTACUS by default which is very costly and not suitable for very high resolution LES. Now CSW_SOLVER_NAME='Tripleclouds' and CLW_SOLVER_NAME='Tripleclouds'.

  • ECRAD: aerosol optics file was aerosol_ifs_rrtm_tegen.nc, now it is aerosol_ifs_rrtm_49R1.nc with 12 aerosol types

  • LSUB_COND=T: the subgrid cloud condensation scheme is now activated by default in NAM_NEBn

  • XTKEMIN: the minimum TKE value applied in each grid cell is now \(10^{-6}\) m²/s² as in AROME (previously 0.01 m²/s²)

  • NMAXITER_MICRO=1 : before was 5 and caused consequently larger simulations duration with microphysics ICE3 in NAM_PARAM_ICEn

  • DEAR and DELT mixing length: a change in the constant in front of the Deardorff and Delt mixing length as following Lemarie et al. 2021. A new key is set LLEMARIE21=T by default.

  • LIO_COMPRESS=T: compression of netCDF is activated by default in NAM_CONFIO namelist.

Radiation scheme - ECRAD 1.6.1

ECRAD is now compiled by default. You can use either the old radiation scheme (CRAD=’ECMW’) or ECRAD without re-compiling all Méso-NH.

All namelist keys available in ECRAD-offline is now available with Méso-NH (see the reference ECMWF documentation)

Warning

To use ECRAD, you still must link data files found at $SRC_MESONH/src/LIB/RAD/ecrad-1.6.1/data/ in the folder of the simulation (MESONH step).

NAM_PARAM_ECRADn new entries

Fortran name

Fortran type

Default value

CDATADIR

CHARACTER(LEN=511)

.

LDO_SW

LOGICAL

.TRUE.

LDO_LW

LOGICAL

.TRUE.

LDO_SW_DIRECT

LOGICAL

.TRUE.

LDO_CLEAR

LOGICAL

.TRUE.

LDO_CLOUD_AEROSOL_PER_SW_G_POINT

LOGICAL

.TRUE.

LDO_CLOUD_AEROSOL_PER_LW_G_POINT

LOGICAL

.TRUE.

CGAS_MODEL_NAME

CHARACTER(LEN=63)

RRTMG-IFS

CGAS_OPTICS_SW_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

CGAS_OPTICS_LW_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

LUSE_AEROSOLS

LOGICAL

.TRUE.

LUSE_GENERAL_AEROSOL_OPTICS

LOGICAL

.FALSE.

LDO_LW_AEROSOL_SCATTERING

LOGICAL

.TRUE.

NAEROSOL_TYPES

INTEGER

12

NI_AEROSOL_TYPE_MAP

INTEGER(NMAXAEROSOLTYPES)

(1,2,3,4,5,6/)

CAEROSOL_OPTICS_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

aerosol_ifs_rrtm_49R1.nc

CLIQUID_MODEL_NAME

CHARACTER(LEN=63)

SOCRATES

CICE_MODEL_NAME

CHARACTER(LEN=63)

Fu-IFS

LUSE_GENERAL_CLOUD_OPTICS

LOGICAL

.TRUE.

LDO_LW_CLOUD_SCATTERING

LOGICAL

.TRUE.

CIQ_OPTICS_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

CICE_OPTICS_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

CCLOUD_TYPE_NAME

CHARACTER(LEN=511)(:)

mie_droplet

LUSE_THICK_CLOUD_SPECTRAL_AVERAGING(:)

LOGICAL

.TRUE.

CSW_SOLVER_NAME

CHARACTER(LEN=63)

Tripleclouds

CLW_SOLVER_NAME

CHARACTER(LEN=63)

Tripleclouds

COVERLAP_SCHEME_NAME

CHARACTER(LEN=63)

Exp-Ran

LUSE_BETA_OVERLAP

LOGICAL

.FALSE.

XCLOUD_INHOM_DECORR_SCALING

REAL

1.0

XCLOUD_FRACTION_THRESHOLD

REAL

1.0E-6

XCLOUD_MIXING_RATIO_THRESHOLD

REAL

1.0E-9

CCLOUD_PDF_SHAPE_NAME

CHARACTER(LEN=63)

Gamma

CCLOUD_PDF_OVERRIDE_FILE_NAME

CHARACTER(LEN=511)

LDO_SW_DELTA_SCALING_WITH_GASES

LOGICAL

.FALSE.

LDO_3D_EFFECTS

LOGICAL

.TRUE.

LDO_LW_SIDE_EMISSIVITY

LOGICAL

.TRUE.

CSW_ENTRAPMENT_NAME

CHARACTER(LEN=63)

Explicit

LDO_3D_LW_MULTILAYER_EFFECTS

LOGICAL

.FALSE.

XMAX_3D_TRANSFER_RATE

REAL

10.0

XMAX_GAS_OD_3D

REAL

8.0

XMAX_CLOUD_OD

REAL

16.0

LUSE_EXPM_EVERYWHERE

LOGICAL

.FALSE.

XCLEAR_TO_THICK_FRACTION

REAL

0.0

XOVERHEAD_SUN_FACTOR

REAL

0.0

XOVERHANG_FACTOR

REAL

0.0

LDO_NEAREST_SPECTRAL_SW_ALBEDO

LOGICAL

.FALSE.

LDO_NEAREST_SPECTRAL_LW_EMISS

LOGICAL

.FALSE.

XSW_ALBEDO_WAVELENGTH_BOUND

REAL(:)

-10

XLW_EMISS_WAVELENGTH_BOUND

REAL(:)

-10

ISW_ALBEDO_INDEX

INTEGER(:)

0

ILW_EMISS_INDEX

INTEGER(:)

0

LDO_WEIGHTED_SURFACE_MAPPING

LOGICAL

.TRUE.

IVERBOSESETUP

INTEGER

3

IVERBOSE

INTEGER

1

LDO_SAVE_SPECTRAL_FLUX

LOGICAL

.FALSE.

LDO_SAVE_GPOINT_FLUX

LOGICAL

.FALSE.

LDO_SAVE_RADIATIVE_PROPERTIES

LOGICAL

.FALSE.

  • CDATADIR: Directory containing NetCDF data files

  • LDO_SW: flag to compute shortwave fluxes

  • LDO_LW: flag to compute longwave fluxes

  • LDO_SW_DIRECT: flag to compute direct shortwave fluxes

  • LDO_CLEAR: flag to ompute clear-sky fluxes

  • LDO_CLOUD_AEROSOL_PER_SW_G_POINT: flag to ompute cloud, aerosol and surface shortwave optical properties per g-point

  • LDO_CLOUD_AEROSOL_PER_LW_G_POINT: flag to compute cloud, aerosol and surface longwave optical properties per g-point

  • CGAS_MODEL_NAME: Gas optics model: ‘RRTMG-IFS’, ‘ECCKD’ or ‘Monochromatic’.

  • CGAS_OPTICS_SW_OVERRIDE_FILE_NAME: Path to alternative shortwave ecCKD gas optics file

  • CGAS_OPTICS_LW_OVERRIDE_FILE_NAME: Path to alternative longwave ecCKD gas optics file

  • LUSE_AEROSOLS: flag to represent aerosols

  • LUSE_GENERAL_AEROSOL_OPTICS: Support arbitrary spectral discretization for aerosols (not just RRTMG)

  • LDO_LW_AEROSOL_SCATTERING: Include longwave aerosol scattering?

  • NAEROSOL_TYPES: Number of aerosol types

  • NI_AEROSOL_TYPE_MAP(:): Mapping from input aerosol types to aerosol optics NetCDF file. By default the mapping is 1: Continental background, 2: Maritime, 3: Desert, 4: Urban, 5: Volcanic active, 6: Stratospheric background. Positive integers indexe hydrophobic types, negative integers index hydrophilic types and zero indicates a type should be ignored

  • CAEROSOL_OPTICS_OVERRIDE_FILE_NAME: Path to alternative aerosol optics file

  • CLIQUID_MODEL_NAME: Liquid optics model: ‘SOCRATES’, ‘Slingo’ (1989) or ‘Monochromatic’

  • CICE_MODEL_NAME: Ice optics model: ‘Fu-IFS’, ‘Baran2016’, ‘Yi’ or ‘Monochromatic’. From Fu(1996), Fu et al. (1998), Baran et al. (2016) and Yi et al. (2013)

  • LUSE_GENERAL_CLOUD_OPTICS: Support arbitrary hydrometeor types?

  • LDO_LW_CLOUD_SCATTERING: Include longwave cloud scattering?

  • CLIQ_OPTICS_OVERRIDE_FILE_NAME: Alternative liquid optics file name

  • CICE_OPTICS_OVERRIDE_FILE_NAME: Alternative ice optics file name

  • CCLOUD_TYPE_NAME(:): Optical property model name for each generalized hydrometeor species: ‘mie_droplet’, ‘baum-general-habit-mixture_ice’

  • LUSE_THICK_CLOUD_SPECTRAL_AVERAGING(:): Use thick spectral averaging?

  • CSW_SOLVER_NAME: Shortwave solver. ‘Cloudless’, ‘Homogeneous’, ‘McICA’, ‘Tripleclouds’, ‘SPARTACUS’. Note that the homogeneous solver assumes cloud fills the gridbox horizontally (so ignores cloud fraction) while the cloudless solver ignores clouds completely

  • CLW_SOLVER_NAME: Longwave solver: ‘Cloudless’, ‘Homogeneous’, ‘McICA’, ‘Tripleclouds’ or ‘SPARTACUS’

  • COVERLAP_SCHEME_NAME: Cloud overlap scheme: ‘Max-Ran’, ‘Exp-Ran’, ‘Exp-Exp’ Note that SPARTACUS and Tripleclouds only work with the Exp-Ran overlap scheme

  • LUSE_BETA_OVERLAP: Use Shonk et al . 2010 \(\beta\) overlap parameter definition, rather than the default \(\alpha\)

  • XCLOUD_INHOM_DECORR_SCALING: Ratio of overlap decorrelation lengths for cloud inhomogeneities and boundaries

  • XCLOUD_FRACTION_THRESHOLD: Ignore clouds with fraction below this. Set to 2.5e-5 if COVERLAP_SCHEME_NAME=’Exp-Ran’

  • XCLOUD_MIXING_RATIO_THRESHOLD: Ignore clouds with total mixing ratio below this

  • CCLOUD_PDF_SHAPE_NAME: Cloud water PDF shape: ‘Gamma’ or ‘Lognormal’

  • CCLOUD_PDF_OVERRIDE_FILE_NAME: Name of NetCDF file of alternative cloud PDF look-up table

  • LDO_SW_DELTA_SCALING_WITH_GASES: Apply delta-Eddington scaling to particle-gas mixture, rather than particles only (see Hogan and Bozzo, 2018)

  • LDO_3D_EFFECTS: Represent cloud edge effects when SPARTACUS solver selected; note that this option does not affect entrapment, which is also a 3D effect

  • LDO_LW_SIDE_EMISSIVITY: Represent effective emissivity of the side of clouds (Schafer et al., 2016)

  • CSW_ENTRAPMENT_NAME: Entrapment model (Hogan et al. 2019): ‘Zero’, ‘Edge-only’, ‘Explicit’, ‘Non-fractal’ or ‘Maximum’.

  • LDO_3D_LW_MULTILAYER_EFFECTS: Maximum entrapment for longwave radiation?

  • XMAX_3D_TRANSFER_RATE: Maximum rate of lateral exchange between regions in one layer, for stability of matrix exponential (where the default means that as little as e−10 of the radiation could remain in a region)

  • XMAX_GAS_OD_3D: 3D effects ignored for spectral intervals where gas optical depth of a layer exceeds this, for stability

  • XMAX_CLOUD_OD: Maximum in-cloud optical depth, for stability

  • LUSE_EXPM_EVERYWHERE: Use matrix-exponential method even when 3D effects not important, such as clear-sky layers and parts of the spectrum where the gas optical depth is large?

  • XCLEAR_TO_THICK_FRACTION: Fraction of cloud edge interfacing directly to the most optically thick cloudy region

  • XOVERHEAD_SUN_FACTOR: Minimum tan-squared of solar zenith angle to allow some ‘direct’ radiation from overhead sun to pass through cloud sides (0.06 used by Hogan et al., 2016)

  • XOVERHANG_FACTOR: A detail of the entrapment representation described by Hogan et al. (2019)

  • LDO_NEAREST_SPECTRAL_SW_ALBEDO: Surface shortwave albedos may be supplied in their own spectral intervals: do we select the nearest to each band of the gas optics scheme, rather than using a weighted average?

  • LDO_NEAREST_SPECTRAL_LW_EMISS: same as LDO_NEAREST_SPECTRAL_SW_ALBEDO for longwave emissivity

  • XSW_ALBEDO_WAVELENGTH_BOUND(:): Vector of the wavelength bounds (m) delimiting the shortwave albedo intervals

  • XLW_EMISS_WAVELENGTH_BOUND(:): Vector of the wavelength bounds (m) delimiting the longwave emissivity intervals

  • ISW_ALBEDO_INDEX(:): Vector of indices mapping albedos to wavelength intervals

  • ILW_EMISS_INDEX(:): Vector of indices mapping emissivities to wavelength intervals

  • LDO_WEIGHTED_SURFACE_MAPPING: Planck-weighted surface mapping?

  • IVERBOSESETUP: Setup verbosity level. 1=warning, 2=info, 3=progress, 4=detailed, 5=debug

  • IVERBOSE: Execution verbosity level

  • LDO_SAVE_SPECTRAL_FLUX: Save flux profiles in each band

  • LDO_SAVE_GPOINT_FLUX: Save flux profiles in each g-point

  • LDO_SAVE_RADIATIVE_PROPERTIES: Write intermediate NetCDF file(s) of properties sent to solver (radiative_properties*.nc)?

The following namelists are renamed or replaced:

  • NSWSOLVER is replaced by CSW_SOLVER_NAME

  • NLWSOLVER is replaced by CLW_SOLVER_NAME

  • NLIQOPT is replaced by CLIQUID_MODEL_NAME

  • NICEOPT is replaced by CICE_MODEL_NAME

  • NOVLP is replaced by COVERLAP_SCHEME_NAME

  • NLWSCATTERING is replaced by LDO_LW_AEROSOL_SCATTERING and LDO_LW_CLOUD_SCATTERING

  • NAERMACC is replaced by NAEROSOL_TYPES

Wind turbine - EOL 2.0.1

The wind turbine code is updated from EOL-1.0 to EOL-2.0.1. The main changes are:

  • New kinematic architecture with 6D harmonic floating motion;

  • New controller architecture including now TABLE, JONKM, and ROSCO (new) methods;

  • 3D Gaussian smearing method;

  • Additional time series outputs and optimizations.

&NAM_EOL

NAM_EOL new keys

Fortran name

Fortran type

Default value

XKERNEL_RATIO

REAL

LCONTROL_EOL

LOGICAL

.FALSE.

LNACELLE

LOGICAL

.FALSE.

LTOWER

LOGICAL

.FALSE.

LDIA_EOL

LOGICAL

.TRUE.

LFLOAT_EOL

LOGICAL

.FALSE.

  • XKERNEL_RATIO : ratio of the kernel size in the 3D Gaussian smearing to the mesh size.

  • LCONTROL_EOL : true to use a controller to modify rotational speed and blade pitch angle during the run. Only for CMETH_EOL=’ADR’ or ‘ALM’.

    • .TRUE. activates the controller. More parameterizations are available in the EOL_CONTROL namelist.

    • .FALSE. the rotational speed and blade pitch angle are constant during the simulation (values imposed in CFARM_CSVDATA).

  • LNACELLE : true to model wind turbines nacelle. Only for CMETH_EOL=’ADR’ or ‘ALM’.

    • .TRUE. to simulate wind turbine nacelle.

    • .FALSE. to remove the nacelle body forces.

  • LTOWER : true to model wind turbines tower. Only for CMETH_EOL=’ADR’ or ‘ALM’.

    • .TRUE. to simulate wind turbine tower.

    • .FALSE. to remove the tower body forces.

  • LDIA_EOL : true to write SCADA-like variables in the diachronic file. Only for CMETH_EOL=’ADR’ or ‘ALM’. See Sect. ref{ss:variables_SCADA} for a list of available variables.

    • .TRUE. write variables. They are written into subgroup ‘Turbines’, itself containing one subgroup for each turbine.

    • .FALSE. do not write variables.

  • LFLOAT_EOL : true to activate the floating motions and static positions. Only for CMETH_EOL=’ADR’ or ‘ALM’.

    • .FALSE. do not use floating DOF.

    • .TRUE. use floating DOFs. Each turbine written in CFARM_CSVDATA must have a last column which contains the name of the CSV field containing the prescribed motions. A mean value for static position as well as an amplitude, frequency and phase for dynamic motion can be given as follows:

LFLOAT content

Motion

Mean [m or rad]

Amplitude [m or rad]

Frequency [Hz]

Phase [rad]

Surge

0.00000

0.0000

0.000

0.000

Sway

0.00000

0.0000

0.000

0.000

Heave

10.0000

0.0000

0.000

0.000

Roll

0.00000

0.0000

0.000

0.000

Pitch

0.08727

0.0349

0.200

0.000

Yaw

0.00000

0.0000

0.000

0.000

Note that filling the table with 0.000 will lead to the same behavior as if LFLOAT_EOL = .FALSE. This can be useful if some turbines are floating and some are not.

  • CSMEAR : smearing method of the aerodynamic forces field. New entry:

    • ‘3DGA’ : 3D gaussian kernel. Note that this can increase the computational cost of the simulation. This mode is only available for ALM and ADR (not ADNR).

&NAM_EOL_ALM

NNB_BLAELT is renamed NNB_RADELT

&NAM_EOL_CONTROL

Parametrization of the turbine’s controller. Default data are given for a typical IEA15MW wind turbine controlled with a velocity table. To use with LCONTROL_EOL=.TRUE. in NAM_EOL.

NAM_EOL_CONTROL content

Fortran name

Fortran type

Default value

CMETH_OPS

CHARACTER(LEN=9)

TABLE

CCONTROL_CSVDATA

CHARACTER(LEN=NFILENAMELGTMAX)

data_TABLE.csv

XCON_AVG_PERIOD

REAL

10.0

XCON_DIST_VEL

REAL

240.0

XCON_RAD_VEL

REAL

120.0

  • CMETH_OPS: method for operational state control

    • ‘TABLE’: the rotational velocity and blade pitch angle are linearly interpolated from a table given in CCONTROL_CSVDATA. The inflow velocity used to interpolate is defined as the mean wind on a virtual disk defined by XCON_DIST_VEL and XCON_RAD_VEL and over a time period XCON_AVG_PERIOD.

    • ‘JONKM’: use the ‘baseline’ controller such as proposed in the Ph.D. thesis of JM Jonkman. The pitch control is a PID and the rotational speed is controlled through a mechanical equilibrium based on the 5-region model. This method requires a lot of mechanical data from the turbine, that are given to Meso-NH through the table CCONTROL_CSVDATA.

    • ‘ROSCO’: Reference Open-Source Controller is a wind turbine controller developed by NREL (National Renewable Energy Laboratory). It allows a minimal rotor speed control, which is applicable to large wind turbines such as the IEA 15 MW reference turbine. In this implementation, only Mode 1 of the generator torque control mode type has been considered. Controller information can be found in the ROSCO Controller setup file named DISCON.IN, which is specific for each turbine. These files are available open-source from the ROSCO repository for canonical (reference) turbines. The file CCONTROL_CSVDATA contains theses datas.

    • ‘NONE’: No operational control method applied. Constant values from CFARM_CSVDATA will be used. Intended for testing purposes only.

  • CCONTROL_CSVDATA: Data necessary for the turbine controller. Its definition varies as a function of the chosen control method:

    • ‘TABLE’: Meso-NH will expect four columns: Turbine Name, Velocity (in m/s), Rotational velocity (in rad/s) and Blade pitch angle (in rad). Take care of the sign of the variables (use the same convention as in the CSV file data_farm.csv, described in namelist CFARM_CSVDATA in NAM_EOL_ALM. There can be as much lines as known operating points by the user, but it should be sorted in increasing velocity as the following example:

Turbine name, Velocity [m/s], Rotational vel [rad/s], Pitch [rad]
NREL5MW,         3.0,              -0.734,             -0.00000
NREL5MW,         4.0,              -0.755,             -0.00000
...,             ...,                 ...,             ...
NREL5MW,        19.8,              -1.266,             -0.299684

  • CCONTROL_CSVDATA

    • ‘JONKM’: the user must put the 17 parameters needed for this model in columns, and one line for each type of turbine. The columns are (again, take care of the units!):

Parameter

Units

Turbine name

Filter frequency

rad.s-1

Drivetrain Inertia

kg.m²

Gearbox Ratio

Gearbox efficiency

Cut-in gen speed

rad.s-1

Region 2 start gen speed

rad.s-1

Region 2 start end speed

rad.s-1

Rated rotor speed

rad.s-1

Cut-in gen torque

N.m

Rated gen torque

N.m

Min blade pitch angle

rad

Max blade pitch angle

rad

Torque controller gain

\(N.m/(rad.s^{-1})^2\)

Pitch controller global gain

Pitch proportional gain

s

Pitch integral gain

  • CCONTROL_CSVDATA

    • ‘ROSCO’: if a ROSCO-type controller is chosen, the user must put the 25 parameters needed for this model in columns, and one line for each type of turbine. The columns are described in the following table with the correspondence with DISCON.IN file generated with the ROSCO repository https://github.com/NREL/ROSCO.

Parameter

Units

Turbine name

Pitch to switch to rng 3

rad

Rated Generator speed

rad/s

\(VS_{RefSpd}\)

Min. Generator speed Rng 2

rad/s

\(VS_{MinOMSpd}\)

Generator torque constant in rng 2

\(N.m/(rad.s^{-1})^2\)

\(VS_{Rgn2K}\) convert from \(Nm/rpm^2\)

Prop. Gain gen PI torque controller

\(VS_{KP}\)

Int. Gain gen PI torque controller

s

\(VS_{KI}\)

Above Rated generator torque PI sat.

Nm

\(VS_{ArSatTq}\)

Min generator torque

Nm

\(VS_{MinTq}\)

Wind Turbine rated power

W

\(VS_{RtPwr}\)

Generator efficiency

%

\(VS_{GenEff}\)

Max. torque generator

Nm

\(VS_{MaxTq}\)

Gearbox ratio

\(WE_{GearboxRatio}\)

Rotor inertia

kg m²

Corner freq. LPF

rad/s

\(F_{LPFCornerFreq}\)

Damping coef.

\(F_{LPFDamping}\)

Prop. Gain pitch poly coeff. a

\(s.rad^{-2}\)

fit \(PC_{GS_{KP}}\)

Prop. Gain pitch poly coeff. B

s/rad

fit \(PC_{GS_{KP}}\)

Prop. Gain pitch poly coeff. C

s

fit \(PC_{GS_{KP}}\)

Int. Gain pitch poly coeff. a

\(rad.s^{-2}\)

fit \(PC_{GS_{KI}}\)

Int. Gain pitch poly coeff. B

\(rad.s^{-1}\)

fit \(PC_{GS_{KI}}\)

Int. Gain pitch poly coeff. C

fit \(PC_{GS_{KI}}\)

Pitch control generator Rated speed

\(rad.s^{-1}\)

\(PC_{RefSpd}\)

Max. Physical pitch

rad

\(PC_{MaxPit}\)

File name table Min. Pitch Vs Rotor Torque

.csv

  • XCON_AVG_PERIOD: used if CMETH_OPS = ‘TABLE’. Time period (in seconds) used for the averaging of the upstream wind.

  • XCON_DIST_VEL: used if CMETH_OPS = ‘TABLE’. Distance (in meters) in the hub frame between the hub and the center of the virtual disk used to sample the velocity (positive is upstream, negative is downstream).

  • XCON_RAD_VEL: used if CMETH_OPS = ‘TABLE’. Radius (in meters) of the virtual disk used to sample velocity.

&NAM_EOL_TOWNAC

Parametrization of the turbine’s tower and nacelle. In the current implementation, the tower is represented by a cylinder with NNB_TOWELT sections and the nacelle by a disk of radius R_r (defined in the data_turbine.csv file). Drag forces are deduced from these geometrical shapes. The user can modify the modified drag coefficient. These drag forces are smeared the same way as the body forces of the blades.

NAM_EOL_TOWAC content

Fortran name

Fortran type

Default value

NNB_TOWELT

INTEGER

84

XCD_NAC

REAL

0.68

XCD_TOW

REAL

4.0

  • NEMITTING_ROT: number of rotor that emit tracers. We recommend to limit this number to the number of wind turbines for which the wake meandering will be studied. Having too many additional variables will reduce the code’s performance.

  • NNB_TOWELT: number of elements to add a drag to the tower. We recommend having at least one element per cell size.

  • XCD_NAC: modified drag coefficient of the nacelle.

  • XCD_TOW: modified drag coefficient of the tower.

&NAM_EOL_TRACERS

NAM_EOL_TRACERS content

Fortran name

Fortran type

Default value

NEMITTING_ROT

INTEGER

1

NNB_EMITTING_ROT

INTEGER(:)

(1,0,0,..)

XTRAC_DIST

REAL

120

XTRAC_RAD

REAL

-60

  • NEMITTING_ROT: number of rotor that emit tracers. We recommend to limit this number to the number of wind turbines for which the wake meandering will be studied. Having too many additional variables will reduce the code’s performance.

  • NNB_EMITTING_ROT: list of size NEMITTING_ROT which indicates the indices of tracked turbines.

  • XTRAC_DIST: Distance (in meters) in the hub frame between the rotor hub and the centre of the emitting disk (positive is upstream, negative is downstream).

  • XTRAC_RAD: Radius (in meters) of the emitting disk.

Variables outputs

List of output variables dedicated to Wind turbine are updated.

I/O

Group /SURFEX

In the netCDF files, the majority of the fields related to SURFEX are now stored in a group named /SURFEX. The exceptions are grid coordinates, grid dimensions and some orographic fields. A group can be seen as a folder in which several fields can be stored. This allows to better organize the content of the file and to avoid name conflicts with other fields (there was some collisions). The group /SURFEX is created at the root of the file.

Compression enabled by default

Compression is now enabled by default for all written netCDF files.

As a reminder, compression for all files is enabled or disabled via the LIO_COMPRESS parameter in the NAM_CONFIO namelist.

Note

if LIO_COMPRESS = .TRUE., the parameters LIO_COMPRESS_ALGO and LIO_COMPRESS_LEVEL take precedence over those in the NAM_BACKUP and NAM_OUTPUT namelists (however, no impact if compression is imposed per variable in the outputs).

Zstandard (zstd) compression

The Zstandard compression library (zstd) is now available as a compression algorithm for netCDF files. It is the default compression algorithm for all floating-point variables if compression is activated. If the variable type is different (other than floating-point numbers, e.g., integers), it is automatically forced to DEFLATE (zlib).

Description

Zstandard is a lossless library. It is open-source and developed by Facebook. It is widely used and is supported by many tools and libraries (e.g., Python…). It provides a better compression ratio than zlib/DEFLATE and is much faster for both compression and decompression.

More information about zstd can be found on the following links:

Constraints

  • Not available everywhere (especially the development part). Therefore, it is bundled with Meso-NH.

  • Not hardcoded in HDF5 but is used as a plugin. Therefore, it is necessary to set the HDF5_PLUGIN_PATH environment variable. This variable is automatically set when loading the Meso-NH environment (profile-* files)

  • Need to provide the plugin sources (outside of HDF5)

  • Not necessarily supported/compiled in all NetCDF tools (but is present for NetCDF with recent Python)

  • Only works for floating-point numbers

Warning

Using old tools dealing with netCDF (such as ncview, old python/netCDF modules) will only work if a profile-mesonh is sourced in the console you are running these tools

Namelists

  • &NAM_CONFIO: CIO_COMPRESS_ALGO = 'ZSTD' (overrides CBAK/COUT_COMPRESS_ALGO if LIO_COMPRESS=T)

  • &NAM_BACKUP: CBAK_COMPRESS_ALGO(m) = 'ZSTD'

  • &NAM_OUTPUT: COUT_COMPRESS_ALGO(m) = 'ZSTD'

Allowed values: ZSTD, DEFLATE, or NONE.

  • By default, the compression algorithm is ZSTD (instead of DEFLATE previously).

  • For non-floating-point numbers, if compression is activated and set to ZSTD, it is automatically forced to DEFLATE.

  • Compression algorithm per model (not possible per variable or per box) (possible in theory, but the interest seems negligible).

  • If the algorithm is forced to NONE, compression is disabled, including lossy compression.

  • Allowed compression levels: -99 to 22.

Performance

Example:

  • Modified test case 004_Reunion (resolution x4: 288x320x50)

  • 5 3D fields in real64 in outputs: UT, VT, WT, THT, PABST

  • 10 time steps with 10 backups and 10 outputs

  • Runs on a standard PC

  • gfortran 14.2.0, compiled with -O2.

Performance Comparison

#processes

Compression Algorithm

Compression Level

I/O Time

Total Time

File Size

1

None

40.9 s

405.6 s

9.8 GiB

1

Deflate

4

150.8 s

514.3 s

3.6 GiB

1

Zstd

4

32.3 s

399.0 s

3.6 GiB

1

Zstd

22

1084.5 s

1465.8 s

3.5 GiB

4

None

41.6 s

293.2 s

9.8 GiB

4

Deflate

4

152.8 s

406.6 s

3.6 GiB

4

Zstd

-4

37.6 s

294.4 s

3.6 GiB

4

Zstd

4

40.8 s

292.4 s

3.6 GiB

4

Zstd

22

1059.4 s

1387.9 s

3.5 GiB

Conclusions:

  • zlib/DEFLATE is expensive

  • Zstd is much faster than zlib

  • Zstd compresses as well as zlib

  • A very high compression level is costly in CPU but does not provide significant disk space gains (in this case, at least)

  • Zstd can be faster than no compression (compression faster than writing to disk)

Removal of LFI support (in writing)

Files in LFI format are no longer supported for writing (but still supported for reading).

&NAM_OUTPUT

An additional dimension (the first one) has been added to all &NAM_OUTPUT parameters to indicate the time series number of outputs.

For now, this new dimension is always set to 1. This will allow to have several time series of outputs with different frequencies and/or variables in the future (e.g., one time series every 15 minutes with a selection of 3D fields, and one time series every minute with surface fields).

&NAM_CONFIO

LCDF4, LLFIREAD and LLFIOUT are removed.

Storage of Meso-NH version numbers

Meso-NH version numbers are no longer stored in fields but in netCDF attributes.

  • Removed fields:

    • MNHVERSION

    • MASDEV

    • BUGFIX

    • BIBUSER

  • Added attributes:

    • MNH_VERSION (array of 3 integers)

    • MNH_VERSION_STR: Version in text format (e.g., “6.0.0” or “6.0.0 myversion”)

    • MNH_VERSION_USER: Only if CBIBUSER is not empty

Other changes

  • CF Conventions

    • Updated to version 1.12 (from 1.10)

    • Added quantization variables (quantization_info_*) that provide characteristics of lossy compression and quantization

    • Added quantization attributes and quantization_nsb/nsd required by CF 1.12 conventions for variables reduced with this approach

  • Removal of backward compatibility for files of versions of Meso-NH < 5

ACLIB: Aerosols and Chemistry Library

ACLIB (Aerosols and Chemistry LIBrary) is an external repository which contains the aerosols and chemistry core codes from Méso-NH, MOCAGE and ARPEGE-ALADIN-climat. The main objective of building such library is exposing a single interface to access every existing routines at the CNRM relating to aerosols physics and chemistry. The aerosols and chemistry code of MOCAGE and ARPEGE-ALADIN-climat are now available in Méso-NH (and vice-versa). ACLIB is also plugged into AROME.

The library comes with a new way to set-up parameters with aerosols and gas species: it uses tables in a .csv format which makes easier to define each parameter for individual aerosols more easily than re-compiling the code (i.e. modd_dust.f90 to change parameters of the log-normal distribution). Pre-defined configurations of these tables are provided by each host-models in order to ease the use of their own schemes in different host models.

Note

In Méso-NH, the code of ARPEGE-ALADIN-climat and MOCAGE is now available but have not been adapted nor tested yet. Using these codes needs scientific adaptation with Méso-NH objects and can be done with a scientific coordination of ACLIB team (ACLIB referee for Méso-NH: quentin.rodier@meteo.fr)

Tree structure

The ACLIB sources can be found here:

  • MNH-V6-0-0/src/ACLIB

    • aer

      • scav

      • sedim

      • suflux

      • transfo

      • diag

    • chem

    • aux

  • aer: main interface aer_aclib.f90, main initialization of aerosols propreties from the csv data init_aer_aclib.f90 and definition of the variables in modd_param_aer_aclib.f90

  • aer/scav: scavenging codes of all models, including Méso-NH ones (e.g. aer_wet_dep_kmt_warm.f90)

  • aer/sedim: sedimentation codes of all models, including Méso-NH ones (e.g. sedim_dslt.f90)

  • aer/suflux: dry deposition and emission of other models than SURFEX. For Méso-NH, it is still through SURFEX.

  • aer/transfo: secondary transformations of aerosols corresponding to ORILAM scheme in Méso-NH (ch_orilam.f90)

  • aer/diag: diagnostics: not pluggd to Méso-NH

  • chem: main interface chem_aclib.f90 with all main chemistry code and solvers. For Méso-NH, BASIC.f90, the main ch_*.f90 routines and ch_aer_*.f90 routines for ORILAM scheme. MOCAGE solvers are mocage_*.f90 routines and ARPEGE-ALADIN-climat ones are acch_*.f90

  • aux: auxilliary routines that are not used only in one specific folder but necessary to compile each codes in all host models.

Interfaces and implementation in Méso-NH

Aerosols

  • MNH-V6-0-0/src/MNH

    • ini_modeln.f90

      • CALL INIT_AER_ACLIB: init of aerosols properties and read of csv data

    • modeln.f90

      • CALL AER_ACLIB

  • MNH-V6-0-0/src/ACLIB/aer/aer_aclib.f90

    • CALL AER_ACLIB_EMIS

    • CALL AER_ACLIB_DRYDEP

    • CALL AER_ACLIB_SEDIM

    • CALL AER_ACLIB_SCAV

    • CALL AER_ACLIB_TRANSFO

    • CALL AER_ACLIB_DIAGS

Sedimentation

  • MNH-V6-0-0/src/ACLIB/aer/sedim

    • aer_aclib_sedim.f90

      • CALL SEDIM: sedimentation in MOCAGE

      • CALL TACTIC_SEDIMNT: sedimentation in ARPEGE-ALADIN-climat

      • CALL SEDIM_DSLT: sedimentation in Méso-NH for DUST and SALT

      • CALL CH_AER_SEDIM_n: sedimentation in Méso-NH for aerosols of ORILAM

Note

The routines of sedimentation from dust and salt are merged from MNH-V6-0-0

Scavenging

  • MNH-V6-0-0/src/ACLIB/aer/scav

    • aer_aclib_scav.f90

      • CALL WETSCAV: scavenging in MOCAGE

      • CALL TACTIC_SCAV: sedimscavengingentation in ARPEGE-ALADIN-climat

      • CALL AER_WET_DEP_KMT_WARM: scavenging in Méso-NH for DUST and SALT

Note

The routines of scavenging of ORILAM aerosols are not in ACLIB.

Transformations (secondary in-organic aerosols)

  • MNH-V6-0-0/src/ACLIB/aer/transfo

    • aer_aclib_transfo.f90

      • CALL MOCAERO: MOCAGE transfo

      • CALL TACTIC_CGROWTH, _SO2SO4, _NO3NH4 : ARPEGE-ALADIN-climat transfo

      • CALL CH_ORILAM: Méso-NH ORILAM

The routine of ORILAM-Méso-NH are not in ACLIB/aer/transfo but in ACLIB/chem because it can not be used without the chemistry module

Aerosols of ORILAM

The sedimentation, scavenging and dry deposition of ORILAM aerosols have been externalized from the chemistry, it is now in a new routine ch_aer_ext_orilam.f90:

  • MNH-V6-0-0/src/MNH

    • modeln.f90

      • CALL CH_AER_EXT_ORILAM

        • CALL MNH_TO_AER_ACLIB

          • CALL AER_ACLIB

            • CALL CH_AER_SEDIM_n

        • CALL CH_AER_WET_DEP_n

        • CALL CH_AER_DEPOS

Chemistry solver

For the chemistry solver, a new interface chem_aclib.f90 contains the call to the chemistry monitors:

  • MNH-V6-0-0/src/MNH

    • modeln.f90

      • CALL INIT_CHEM_MODEL: init of other chemistries

      • CALL MNH_TO_CHEM_ACLIB

        • CALL CHEM_ACLIB

  • MNH-V6-0-0/src/ACLIB/chem/chem_aclib.f90

    • CALL CH_MONITOR_n: Méso-NH chemistry monitor

    • CALL CHEM_SUGAR: MOCAGE monitor

    • CALL ACCHEM: ARPEGE-ALADIN-climat monitor

Note that the init of Méso-NH chemistry is not yet moved to init_chem_model.

Note

In the interfaces CHEM_ACLIB and MNH_TO_CHEM_ACLIB, the arguments are written with explicit dimensions because Méso-NH and MOCAGE are using 2 dimensions for latitudes and longitudes whereas ARPEGE-ALADIN-climat uses only 1 dimension (lat/lon are packed). The pack/unpack operations are done correctly at the execution if the arrays are contiguous.

The use of the extra interface MNH_TO_CHEM_ACLIB is necessary for diagnostics allocated with different dimensions regarding the host model.

ACLIB custom types

To ease the use of ACLIB in each host models, new custom types have been created:

  • for individual aerosols and gas species, YCHEMS and YAEROSOLS regroup the definition of each individual chemical species and aerosols.

  • for general parameters for aerosols and chemistry schemes YPAER_ACLIB and YPCHEM_ACLIB are defined.

  • for diagnostics, YAEROUT_ACLIB and YCHEMOUT_ACLIB are defined (not yet used in Meso-NH).

  • for general constants used in ACLIB, CST_ACLIB is defined.

ACLIB objects

Object name

Definition

Initialization

Data source

YCHEMS

chem/modd_param_chem_aclib.f90

chem/init_chem_aclib.f90

Table_chem_species_aclibn.csv (example)

YPCHEM_ACLIB

chem/modd_param_chem_aclib.f90

chem/init_chem_aclib.f90

Table_chem_general_aclibn.csv (example)

YAEROSOLS

aer/modd_param_aer_aclib.f90

aer/init_aer_aclib.f90

Table_aer_species_aclibn.csv (example)

YPAER_ACLIB

aer/modd_param_aer_aclib.f90

aer/init_aer_aclib.f90

Table_aer_species_aclibn.csv (example)

CST_ACLIB

aux/modd_cst_aclib.f90

aer/init_cst_aclib.f90

CSV input parameters

To ease the use of ACLIB within different host models, a common input parameters format has been designed using csv tables (see the list in the previous section).

For aerosols, Table_aer_general_aclibn.csv, with n the Méso-NH domain number, defines general options such as the number of total aerosols/modes used, the number of families (dust, salt, etc) and the code wanted for each processus (sedimentation, scavenging, deposition, emission, and transformation).

The same general csv table is for chemical species.

For a smooth transition from the classic FORTRAN Méso-NH namelist to csv format, a new namelist is available

NAM_ACLIB new entries

Fortran name

Fortran type

Default value

LUSEAERTABLE

LOGICAL

.FALSE.

LUSECHEMTABLE

LOGICAL

.FALSE.

  • LUSEAERTABLE: true to use Table_aer_general_aclibn.csv to read namelist input instead of the traditional namelist for some aerosols general parameters

  • LUSECHEMTABLE: true to use Table_chem_general_aclibn.csv to read namelist input instead of the traditional namelist for some chemistry general parameters

Note

By default, Table_aer_general_aclibn.csv and Table_chem_general_aclibn.csv are ignored (not read). Traditional Méso-NH namelist is used.

Warning

The Table_aer_species_aclibn.csv are always read, so using NAM_DUST, NAM_SALT or NAM_CH_ORILAM must be carefully cross-checked with the Tables!

The Table_chem_species_aclibn.csv are not read/implemented yet.

How to code in ACLIB ?

ACLIB is shared with other models. Specific rules must be followed:

  • Use explicit dimensions in variable declaration

  • Do not add Méso-NH specific modules/variables into ACLIB, but add variables through the interfaces instead. If a new specific module is needed, make sure that this module is Méso-NH agnostic (not dependent of other Méso-NH specific modules that would be incompatible with other host models)

  • Use dedicated ACLIB custom types as it is implemented (e.g. use CST_ACLIB for constants and not MODD_CST from MesoNH world)

  • Internal routines in src/ACLIB must be agnostic from parallelization as much as possible to ease future use of cross-codes in different host models.

PHYEX

Turbulence

NAM_TURBn new entries

Fortran name

Fortran type

Default value

LGOGER

LOGICAL

.FALSE.

XSMAG

REAL

0.2

LDYNMF

LOGICAL

.FALSE.

LTHERMMF

LOGICAL

.TRUE.

LBL89TOP

LOGICAL

.FALSE.

LBL89EXP

LOGICAL

.TRUE.

LLEMARIE21

LOGICAL

.TRUE.

  • LGOGER: true to compute the Goger terms

  • XSMAG: dimensionless Smagorinsky constant

  • LDYNMF: true to take into account a dynamical TKE production from EDMF

  • LTHERMMF: true to take into account a buoyancy TKE production from EDMF

  • LBL89TOP: true to limit BL89/RM17 at PBL top (as in ARPEGE)

  • LBL89EXP: true to use the exposant from the BL89 paper ( which is LOG(16.)/(4.*LOG(XKARMAN)+LOG(XCED)-3.*LOG(XCMFS))). Otherwise 2./3. (False in AROME cycl 50t1)

  • LLEMARIE21: true to use Lemarie et al. 2021 constant in DELT/DEAR mixing length (\(0.5^{-6/7}\) instead of \(0.5^{-1.5}\))

Shallow convection

NAM_PARAM_MFSHALLn new entries

Fortran name

Fortran type

Default value

CWET_MIXING

CHARACTER(LEN=4)

‘PKFB’

CKIC_COMPUTE

CHARACTER(LEN=4)

‘KFB’

CDETR_DRY_LUP

CHARACTER(LEN=4)

‘SURF’

LMIXTKE

LOGICAL

.FALSE.

XSIGMA_ENV

REAL

0

LPZ_EXP_LOG

LOGICAL

.FALSE.

XBRIO

REAL

0

XAADVEC

REAL

0

LRELAX_ALPHA_MF

LOGICAL

.FALSE.

  • CWET_MIXING : type of env mixing for buoyancy sorting scheme (‘PKFB’ for the original Pergaud code, ‘LR01’ for Lappen and Randall [2001])

  • CKIC_COMPUTE : method to compute KIC (‘KFB’ to use the PMMC09 original method, like in KFB, ‘RS08’ to use the De Rooy and Siebesma [2008] formulation)

  • CDETR_DRY_LUP : upward length to use in the dry detrainement (‘SURF’ to use \(L_{UP}\) at surface (original PMMC09 Pergaud et al. [2009]), ‘UPDR’ to compute \(L_{UP}\) in updraft)

  • LMIXTKE : flag to mix the prognostic variable TKE by updrafts. Only implemented with CMF_UPDRAFT='EDKF'

  • XSIGMA_ENV: coefficient for the environment sigma contribution in the bigaussian scheme

  • LPZ_EXP_LOG: true to use exp/log during dP/dZ conversion to respect hydrostatic approximation to interpolate z and p between two half-level and full-level points, false to use linear interpolation (old interpolation, not recommended)

  • XBRIO : coefficient to slow down wup equa like Rio et al. [2010]

  • XAADVEC : coefficient for advective pressure perturbation like He et al. [2020]

  • LRELAX_ALPHA_MF: true to relax the small fraction assumption

ICE3

NAM_PARAM_ICEn new entries

Fortran name

Fortran type

Default value

LKOGAN

LOGICAL

.FALSE.

LMODICEDEP

LOGICAL

.FALSE.

LEXCLDROP

LOGICAL

.FALSE.

LEXT_TEND

LOGICAL

.FALSE.

  • LKOGAN: true to use Kogan autocoversion of liquid

  • LMODICEDEP: flag for alternative deposition/evaporation coefficients of water vapor on ice, snow and graupel

  • LEXCLDROP: true to use of external cloud droplet concentration (as from near-real time aerosols) instead of constant values on land/sea masks. Only useable in HARMONIE-AROME and not yet Meso-NH

  • LEXT_TEND: true to use external tendencies during the time-splitting

  • CSUBG_MF_PDF: new option ‘BIGA’. Current available options are ‘NONE’ or ‘TRIANGLE’ (see NAM_PARAM_ICEn)

LIMA

NAM_PARAM_LIMA new entries

Fortran name

Fortran type

Default value

LICE3

LOGICAL

.FALSE.

LSIGMOIDE_G

LOGICAL

.FALSE.

LSIGMOIDE_NG

LOGICAL

.FALSE.

XSIGMOIDE_G

LOGICAL

1E8

XMVDMIN_G

LOGICAL

125E-6

LCRIAUTI

LOGICAL

.FALSE.

XPSH_MAX_RDSF

REAL

0.2

XT0CRIAUTI

LOGICAL

(LOG10(XCRIAUTI)-XBCRIAUTI)/0.06

XCRIAUTI

REAL

0.2E-4

XCRIAUTC

REAL

0.5E-3

XACRIAUTI

REAL

0.06

XBCRIAUTI

REAL

-3.5

CSUBG_PR_PDF

CHARACTER(LEN=4)

‘SIGM’

CSUBG_AUCV_RC

CHARACTER(LEN=4)

‘NONE’

CSUBG_AUCV_RI

CHARACTER(LEN=4)

‘NONE’

LCRYSTAL_SHAPE

LOGICAL

.FALSE.

NNB_CRYSTAL_SHAPE

INTEGER

1

HTYPE_CRYSTAL

CHARACTER(LEN=4)(:)

NNB_CRYSTAL_SHAPE * ‘’

LICE_ISC

LOGICAL

.FALSE.

LINITORILAM

LOGICAL

.FALSE.

LINTERP_CAMS

LOGICAL

.FALSE.

LFREEZ_RATE

LOGICAL

.TRUE.

  • LICE3: Use to mimic the ICE3 scheme. If set to .TRUE., some parameters are set :

NMOM_C=1
NMOM_R=1
NMOM_I=1
NMOM_S=1
NMOM_G=1
NMOM_H=MIN(NMOM_H,1)
NMOD_CCN=0
NMOD_IFN=0
LMURAKAMI=.TRUE.
LKESSLERAC=.TRUE.
XALPHAR=1.
XNUR=1.

  • LSIGMOIDE_G: true to limit graupel growth by XSIGMOIDE_G

  • XSIGMOIDE_G: sigmoide parameter for graupel growth limitation

  • LSIGMOIDE_NG: true to force lambda to be < lambda(Dmin)

  • XMVDMIN_G: minimum MVD for graupel growth lim or lambda(Dmin) calculation

  • LCRIAUTI: true to compute XACRIAUTI and XBCRIAUTI (from XCRIAUTI and XT0CRIAUTI). If false, XT0CRIAUTI is computed from XCRIAUTI and XBCRIAUTI.

  • XPSH_MAX_RDSF: shattering probability normal distribution maximum

  • XT0CRIAUTI: threshold temperature for the ice->snow autoconversion threshold

  • XCRIAUTI: minimum value for the ice \(\rightarrow\) snow autoconversion threshold

  • XACRIAUTI: A parameter for the ice \(\rightarrow\) snow autoconversion 10**(aT+b) law

  • XBCRIAUTI: B parameter for the ice \(\rightarrow\) snow autoconversion 10**(aT+b) law

  • CSUBG_PR_PDF: PDF for subgrid precipitation. Options are the same as in NAM_PARAM_ICEn.

  • CSUBG_AUCV_RC: type of subgrid rc->rr autoconversion method. Options are the same as in NAM_PARAM_ICEn.

  • CSUBG_AUCV_RI: type of subgrid ri->rs autoconversion method. Options are the same as in NAM_PARAM_ICEn.

  • LCRYSTAL_SHAPE: true to enable several ice crystal shapes. It can only be used if LPTSPLIT=T.

  • NNB_CRYSTAL_SHAPE: number of ice crystal shapes ; taken into account if LCRYSTAL_SHAPE=T. For the moment, only 4 ice crystal shapes are allowed.

  • HTYPE_CRYSTAL_SHAPE: ice crystal shapes if LCRYSTAL_SHAPE=T. Can be set to YPLA, YCOL, YBUR or YDRO.

  • LICE_ISC: true to enable self collection of ice crystals

  • LINITORILAM: true to initialize CCN and IF by ORILAM

  • LINTERP_CAMS: true to interpolate CAMS data at each time step (from Large-Scale fields)

  • LFREEZ_RATE: true to limit riming efficiency (heat budget on icy hydrometeors collecting supercooled liquid water)

Condensation

NAM_NEBn new entry

Fortran name

Fortran type

Default value

LCONDBORN

LOGICAL

.FALSE.

  • LCONDBORN : true to limit condensation: reduce the distribution width with respect to te total water content to avoid condensate too much water vapor not present

Other namelist changes

&NAM_CONF

  • CINIT_LG: the FMOUT option has been renamed to BACKUP.

&NAM_DUST

&NAM_DUST new entry

Fortran name

Fortran type

Default value

LPASPOL_DST

LOGICAL

.FALSE.

LSED2MOM_DST

LOGICAL

.FALSE.

  • LPASPOL_DST: emit dust aerosols instead of passive scalar. Use with turning off physics-based surface dust emission LEMIS_DST from &NAM_SURF_DST

  • LSED2MOM_DST: flag to activate multimoment sedimentation

&NAM_LBCn

NLBLX,NLBLY are deleted (not used in the code).

&NAM_LES

&NAM_LES new entry

Fortran name

Fortran type

Default value

LCOARSEGRAIN

LOGICAL

.FALSE.

NCOARSEGRAIN

INTEGER

1

NSIZECOARSEGRAIN

INTEGER(:)

  • LCOARSEGRAIN: flag to activate coarse-graining online diagnostics of resolved TKE, turbulent vertical flux of \(r_t\) and \(\theta_l\). Additionnal fluxes terms are saved on if LCONDSAMP=T

  • NCOARSEGRAIN: number of coarse-graining sub-domains

  • NSIZECOARSEGRAIN: dimension sizes in terms of number of points for all coarse-graining sub-domains

&NAM_PARAM_RADn

The documentation of NAM_PARAM_RADn has been updated to better describe which options are common for all radiations code and which ones are only used for the old radiation scheme (not ECRAD).

Renaming parameters for CEFRADL and CEFRADI:

  • CEFRADL: the C2R2 option has been renamed to 2MOM

  • CEFRADI: the C3R5 option has been renamed to 2MOM

&NAM_PASPOL

&NAM_PASPOL new entry

Fortran name

Fortran type

Default value

NMODEL_PP

INTEGER

1

  • NMODEL_PP: model number where passive pollutants are emitted

&NAM_SALT

&NAM_SALT new entry

Fortran name

Fortran type

Default value

LSED2MOM_SLT

LOGICAL

.FALSE.

  • LSED2MOM_SLT: flag to activate multimoment sedimentation on sea salts

&NAM_SURF_DST

&NAM_SURF_DST new entry

Fortran name

Fortran type

Default value

LEMIS_DST

LOGICAL

.FALSE.

  • LEMIS_DST: flag to activate emission of dust (to be used with LPASPOL_DST)

Cleaning and restructuration

  • The src/LIB/SURCOUCHE directory has been removed. It contained source files for parallelization and for I/O. They all have been moved to the src/MNH/parallel and src/MNH/io directories.

  • Subdirectories in the src/MNH directory have been created. The src/MNH directory contained a lot of files with different functionalities. To better organize the code, several subdirectories have been created and files have been moved. This is only a first step and more restructuring will be done in the future.

  • The MY_RUN directory has been renamed to examples.

  • The MY_RUN/KTEST directory has been renamed to examples/test_cases.

  • The other examples/* (formerly MY_RUN/*) subdirectories are now lowercase. This does not apply to the test case directories, which keep their original name (usually in capital letters).

  • The bin_tools directory has been removed. It contained executables that are no longer supported and that do not work on current machines.

  • The LIBTOOLS directory has been removed. It contained mostly old tools and libraries that are no longer supported.

  • The src/include directory has been removed. Only the ISORROPIA chemistry model has been kept and moved to the src/LIB/ISORROPIA directory.

  • The LFI2CDF tool has been renamed to CDF2CDF and moved to MNH/.

  • Configuration files, rules for compilation, examples of jobs… for obsolete machines and architectures have been removed.

  • The grib_api library has been removed. It is no longer maintained (since 2017) and does not work with recent GRIB files. It is replaced by the ECCODES library.

  • The src/ARCH_SRC directory has been cleaned. Obsolete sources have been removed.

HRRR-WRF and ICON as initialization and forcing models

  • HRRR-WRF: Initializing and forcing Méso-NH with daily operational model HRRR is now possible. More info in Extract HRRR data

  • ICON: Initializing and forcing Méso-NH with daily operational model ICON-EU or ICON-Global is now possible. More info in Extract ICON data

Miscellaneous changes

Balloons: improved vertical position calculation

  • Reduced time step to improve numerical stability if necessary:

    • Originally, max 1 second

    • Now, if the speed is too high, it tries 0.1 second

    • If still too high, a forced crash occurs

  • Recalculates air density and vertical speed at each intermediate time step (changes significantly if the time step is large and/or the balloon moves quickly)

Microphysics: removol of C1R3 and C3R5 schemes

The C1R3 and C3R5 microphysics schemes have been removed from the code. These schemes were not maintained, not documented, and not used in any example test case. &NAM_DYNn LHORELAX_SVC1R3 is deleted.