meso-nh model
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Meso-NH model
30 users laboratories
http://www.aero.obs-mip.fr/mesonh
A research model, jointly developped by Meteo-France and Laboratoire d’Aérologie (CNRS/UPS)
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
General description of Meso-NH
Anelastic equations with the pseudo-incompressible system of Durran
• Vertical coordinate following the terrain : (Gal Chen and Sommerville, 1975)
• Temporal discretization : Purely explicit leap-frog scheme
• Advection scheme : 2nd order eulerian schemes
•Spatial discretization : Arakawa C grid
• Grid nesting : One-way/Two-way
• Initial fields and LBC (radiative open) from ECMWF/ARPEGE/ALADIN.
S
S
zH
zzHz
•Turbulence : 1.5 order closure Cuxart-Bougeault-Redelsperger (2000)
• Convection : Kain-Fritsch (1993) revised by Bechtold et al. (2001)
• Microphysical scheme : Bulk schemes at 1-moment or 2-moments. Up to 7 prognostic species: vapor (rv), cloud (rc), rain (rr), pristine ice (ri), snow (rs), graupel (rg), hail (rh)
• Radiation : ECMWF package
• Chemical on-line scheme : Gazeous and aerosols (Presentation C.Mari, Thursday)
• Externalized surface model (Presentation P.Le Moigne, this afternoon)
DYN
AM
ICS
PH
YSIC
S
Types of simulationsTypes of simulations
A broad range of resolution from synoptic scales A broad range of resolution from synoptic scales ((x~10km) to meso-scale (x~10km) to meso-scale (x~1km) to Large x~1km) to Large Eddy Simulation (Eddy Simulation (x~10m) x~10m)
• Real cases (from ECMWF, ARPEGE, ALADIN Real cases (from ECMWF, ARPEGE, ALADIN analyses or forecasts)analyses or forecasts)
• Ideal cases Ideal cases unrealistic cases unrealistic cases- Academic cases (validation of the - Academic cases (validation of the
dynamics)dynamics)- Basic studies (Diurnal cycle …) : Cloud - Basic studies (Diurnal cycle …) : Cloud
Resolving Model (CRM)Resolving Model (CRM)- To reproduce an observed reality (via - To reproduce an observed reality (via
forcings)forcings)(intercomparison : GCSS, EUROCS …)(intercomparison : GCSS, EUROCS …)
Simulations 3D, 2D, 1DSimulations 3D, 2D, 1D
Grid nesting technics
At every time step :
The Coarse Model (CM) gives the lateral boundary conditions to Fine Model (FM) by interpolation
One-way : the FM doesn’t influence the CM
Two-way : CM fields are relaxed to the average of FM fields
A single constraint : an integer ratio between the resolutions and the time stepsSame vertical grids.
Vaison-la-Romaine : 22 september 1992
3 nested grids : 40/10/2.5km
Instantaneous precipitations 2.5km
One-way Two-way
Stein et al., 2000
Cumulated precipitations for 9h(Obs=300mm en 6h)
One-way Two-way
Stein et al., 2000
2.5 km
10km
Vaison-la-Romaine : 22 september 1992
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
Mixed phase cloud representation with a bulk
scheme
0°C 0°C
Mixed phase :
Liquid phase :
Ice crystals
Snowflakes
Graupel
Hail
Cloud droplets
Cloud properties = f( , , , , , )
Cloud droplets
Raindrops
0°C
Autoconversion
0°C
The different processes
RimingAggregation
Collection Collection
Deposition
Freezing
Nucleation
Melting
Sedimentation
MESO-NH Explicit microphysical scheme :
Instantaneous precipitation
2.5km2-way without ICE
2-way with ICE
Stein et al., 2000
Lafore Moncrieff 89
Stratiform
Density Current
Convective
HD
A tropical squall line (P.Jabouille) : Idealized
simulation according to a real case (COPT81)
U
W
Cloud droplets Rain drops
Pristine iceGraupel
Snow
Jabouille. Caniaux et al., 1994
Three contrasted MAP cases
IOP 2A
Strong Convection
IOP 3
Moderate Convection
IOP 8
Stratiform rain
F.Lascaux and E.Richard, 2005
18:00 UT
19:00 UT
20:00 UT
Microphysical retrievals : IOP 2A (intense convection)
12
km
100 kmTabary, 2002
(x) hail + graupel
(o) hail ( ) rain
Z > 60 dBz
Radar Retrieval (S-Pol)
Simulation (Meso-NH)
(x) hail + graupel
(o) hail
graupel
hail
18:00 UT
19:00 UT
20:00 UT
rain rain
12
km
100 km
Hydrometeor type
(o) hail
(x) hail + graupel
hail + graupel
dry snow
rain
Pujol et al., 2005
Microphysical retrievals - IOP 3 (moderate convection)
18:10 UT
18:30 UT
Microphysical retrievals - IOP 3 (moderate convection)
hail + graupel
S-Pol retrieval Meso-NH simulation
snow snow
rain rain
Microphysical retrievals - IOP 8 (stratiform rain)
Meso-NH simulationS-Pol retrieval
rain
snow
melting snow
Medina et Houze, 2003
Microphysical budgets : Mean vertical distribution of the hydrometeors
Lascaux et al., 2005
graupel
IOP 2Aice
snow
hail
cloudrain
IOP 8
cloudrain
snow
IOP 3
ice
rain
IOP 2A IOP 3 IOP 8
Microphysical budgets : mean vertical distribution of the different processes
max : 135 mm
max : 25 mm
m mm
Quasi-stationnary MCS 13-14 Oct. 1995
Cumulated precipitation 01 UTC to 06 UTC the 14th Oct. 1995
MESO-NH, x=10km
max: 31 mm
MESO-NH, x=2.5kmOBSERVATIONS
(Ducrocq et al, 2002)
Initial conditions: ARPEGE analysis at 18UTC
mMESO-NH, x=2.5km
Initialisation Ducrocq et al
(2000)’s
max : 99 mm
Sensitivity to initial conditions Sensitivity to initial conditions
+Nîmes
+Nîmes
Observations
Nîmes radar
Raingauges
Initial Conditions : ARPEGE analysis12UTC, 08/09/02
+
MESO-NH (2.5km)
12-h accumulated précipitation from 12 UTC, 8 Sept to 00 UTC, 9 Sept 2002
Gard flash-flood (8-9 Sept.2002)Initial
Conditions : Ducrocq et al (2000) Initialisation12UTC, 08/09/02
+
(Ducrocq et al, 2004)
Ducrocq V, F.Bouttier Météo-France SRNWP/Met Office/Hirlam workshop on Variational Methods Exeter (UK) 15-17 Nov 2004
TROCCINOX 2005
Chaboureau et al., 2005
Méso
-NH
Obse
rvati
on
Tb 10.8 m Diff 8.7 - 10.8 m
CirrusConvection
Geophysica
The approach Model towards Satellite to validate the cloud coverage
Stratocumulus : Capped BL
When the CBL is blocked by an anticyclonic subsidence
FIRE 1 case of EUROCS : Forcing terms : a LS subsidence + cooling (dl/dt<0) and moistening (dqt/dt>0) under the inversion to balance the subsidence
alt
itu
de (
m)
Cloud water mixing ratio (kg/kg)
Min = 0.025 g/kg
Max = 0.6 g/kg
0h 12h 0h 12h 0h
LES simulation of the diurnal cycle (x=50m)
Observations of the base and the top cloud layer Sandu et al., 2006
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• CyclonesCyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
Simulation of cyclone : case of Dina7800 km, x=36km
1944 km , x=12km
720 km , x=4km
3600 km
Automatic method of Initialization : Filtering/Bogussing
Barbary et al.
Simulations CEPMMT : trajectoires 22/01/02 00 UTC
Barbary et al.
Évolution en intensité( a ) Minimum de pression (MSLP)
920
930
940
950
960
970
980
990
0 6 12 18 24 30 36 42
échéance (heures)
MS
LP
(h
Pa)
( b ) Vent maximum à 10 mètres
0
10
20
30
40
50
60
70
0 6 12 18 24 30 36 42
échéance (heures)
Vm
ax (
m/s
)
( c ) Rayon de vent maximum (RMW)
0255075
100125150175
0 6 12 18 24 30 36 42
échéance (heures)
RM
W (
km)
Best Track CEP Prévision
Méso-NH CEP 36km Méso-NH CEP 4km Barbary et al.
Vertical cross-sections at x=4km
K
m/s
K
m/s
TC
Lq
EPe.
Horizontal wind
S-N W-E
Barbary et al.
Fine scale structure (1 km)le 22 janvier 17h10-17h20-17h30
dBZ
10-3s-1
Radar reflectivity
Relative vorticity
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surfaceCoupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
LakeTownSeaNature
Méso-NH AROME Arpège / Aladin
SURFACE
EXTERNALIZED SURFACE :
Exchange of data flow at each time step between the 2 models
Atmosphere forcing Sun position Radiative fluxes
albedo emissivity radiative temperature
fluxes : Momentum, heat, water vapor, CO2, chemistry
Boundary conditions for turbulence and radiative schemes
Presentation of P.Le MoignePresentation of P.Le Moigne
Set-up :
4 grid-nesting models from regional to city scale, with respective resolutions of 12 km, 3 km, 1 km and 250 m
3D Meso-NH simulations (Lemonsu et al., 2004, 2005)
500
400
300
200
100
50
(m)
600
700
France
Mer Mediterranée
2000
1000
500
200
100
50
(m)
Mer Mediterranée
2000
1000
500
200
100
50
(m)
Marseille
Mer Mediterranée
2000
1000
500
200
100
50
(m)
Marseille
Model 1
Model 2
Model 3Model 4
Chaine de l’Etoile
Mont St-Cyr
MarseilleveyrePuget
N.D. de la Garde
Validation of
simulations
at regionalregional scale
Validation of
simulations
at urbanurban scale
Mediterranean Sea
Marseille veyre
Massif du Puget
City centre
500
1000
1500
2000
2500
Alt
itude (
m)
21 juin
22 juin
23 juin
24 juin
25 juin
26 juin
Obs
Model
500
1000
1500
2000
2500
Alt
itude (
m)
St Rémy
Radiosoundings
St Rémy de Provence
Regional validation
Thermodynamic structures
Urban network
Model
Air temperature inside the streets
26 June 2001, 1400 UTC
Lemonsu et al., 2005a
6 m s-1420-2-4-6
26 June 2001, 1400 UTC
B
C
D
A
TWL
B
C
D
A
Model
VDOL
City cente
r0 2 4 6 0 2 4 6Distance (km) Distance (km)
VDOL
City cente
r
0.5
1.0
1.5
2.0
2.5
Alt
itude (
km
)
Lemonsu, Bastin et al., 2005b
500
400
300
200
100
50
ZS (m)
Marseilleveyre
190o
Puget MassifCNRS
(Radar)
3 km
VAL (Lidar)
OBS (Radar)
Etoile Massif
Comparison with transportable wind lidar (TWL)
W
VAL
OBS
CNRS
m s-1
Puget Massif
Marseilleveyre
City centre
VAL
OBS
CNRSPuget Massif
Marseilleveyre
City centre
z = 400 m AGL
z = 50 m AGL
West SSB
South SSB
South-East DSB
Atmospheric boundary layerHorizontal wind field
26 June 2001, 1400 UTC
Without townRealistic
TKE
x=1km
Simulation on PARISDAY
Lemonsu et Masson (2001)
Nocturnal UBL
Without townRealistic
Lemonsu et Masson (2001)
Masson (2001)
Formation of fog
CarboEurope/RE : modélisation Meso-NH/ISBA-A-gsC.Sarrat et al., CNRM/GMME/MC2
Modelisation of the atmospheric CO2 in interaction with the surface : coupling of CO2 in Meso-NH with CO2 fluxes of
ISBA-A-gs • Improvement of the exchanges surface-atmosphere • Improvement of water cycle/ evapotranspiration• Improvement of the PBL representation• Regional budget of CO2 atmosphérique• Inversion of CO2 concentrations to identify
sources/sinks of CO2 (Thèse T. Louvaux)
ISBA-A-gs
Met. forcing LE, H, Rn, W, Ts…
CO2 Flux[CO2]atm
Anthropogenic
Sea
Meso-NH Surface
Modélisation 3-D : Configuration
Domaine : France (900x900 km)Résolution horizontale : 10 kmPas de temps : T = 10 s
Domaine : Landes (320x250 km)Résolution horizontale : 2.5 kmPas de temps : T = 5 s
Nesting 2 ways Surface : ISBA-A-gs (Ecoclimap) Vertical grid : 60 levels (0 -14000m)
Modélisation 3-D : Résultats
RN
LE
H
SFCO2
[CO2]
CarboEurope/RE : modelisation Meso-NH/ISBA-A-gs and atmospheric CO2
[CO2] simulated at 15H (june 2001)Advection + Assimilation + vertical mixing [CO2] decrease
00H : Advection + Respiration + cooling [CO2] increase
Coupling of Meso-NH with other models (Hydrology,
Dispersion)
VidourleVidourle
GardGard
CèzeCèze
ArdècheArdèche• TOPMODEL (Beven and Kirkby,
1979) distributed hydrologic model with one model by basin : 9 basins (200-2200 km²)
• Objectives :- Flow and rapide flood forecasts- Retroaction of the hydrology on the atmosphere- Available for AROME
HYDROLOGY : Development of the coupling Meso-NH-ISBA-TOPMODEL
K.Chancibault et al., CNRM/GMME/MICADO
Strategy of the coupling
Meso-NH ou Arome
ISBA TOPMODEL
Module de routage
t = 5 minx = 2-3 kmL = 1000 km
t = 5 minx = 2-3 kmL = 1000 km
t = 1hx = 50 mL = 1 km
Wmob
flux
120km, x=2km
30km, x=500m
Dispersion with passive tracers : case of AZF
Tulet et Lac (2001)
Vertical cross-section
30min after the release
the release
SPRAY• Lagrangian particle model•At least 10000 particles released •Advection+Turbulence+random• Applied to the 2 Meso-NH grids
PERLEPERLE (PProgramme d’EEvaluation des RRejets L Locaux d’EEffluents)
Dispersion
Meso-NH • 2 grids (Regional x=8km, L=240km/ Local x=2km, L=60km)• 36 levels until 16km• ALADIN initialization and coupling
Meso-scale meteorology
Will be exported to AROME
Modelling system for environmental emergency
Concentrations à Z=10m Concentrations à Z=800m
Source
BLAG NAC
CO LO M IERS
M UR ET
TO ULO USE
TO UR NEFEUILLE
C o u p e h or izon ta le a 10 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 2 0 U T C
1E -006
1E -005
1E -004
1E -003
1E -002
0m 500 0m 100 00m 150 00m 200 00m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 1 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 2 5 U T C
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
1 E -0 0 2
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 1 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 3 0 U T C
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
1 E -0 0 2
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 1 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 4 0 U T C
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
1 E -0 0 2
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAG NAC
CO LO M IERS
M URET
TO ULO USE
TO URNEFEUILLE
C o u p e h o r izo n ta le a 1 0 m
C o n c (g /m 3 ) le 2 1 .0 9 .2 0 0 1 a 0 8 h 5 0 U T C
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
1 E -0 0 2
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAG NAC
CO LO M IERS
M UR ET
TO ULO USE
TO UR NEFEUILLE
C o u p e h or izon ta le a 10 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 9 h 0 0 U T C
1E -006
1E -005
1E -004
1E -003
1E -002
0m 500 0m 100 00m 150 00m 200 00m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 3 0 U T C
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 4 0 U T C
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 8 h 5 0 U T C
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 9 h 0 0 U T C
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C on c (g /m 3) le 21 .09 .20 0 1 a 0 9 h 1 0 U T C
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
1 E -0 0 4
1 E -0 0 3
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Méso-NH + SPRAY
Temps de réponse=
25min
Source
BLAGNAC
CO LOM IERS
M URET
TO ULO USE
TOURNEFEUILLE
C o u p e h o r izo n ta le a 1 0 m
C T A
1 E -0 0 9
1 E -0 0 8
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
Source
BLAG NAC
CO LO M IERS
M URET
TO ULO USE
TO URNEFEUILLE
C o u p e h o r izo n ta le a 8 0 0 m
C T A
1 E -0 0 9
1 E -0 0 8
1 E -0 0 7
1 E -0 0 6
1 E -0 0 5
0 m 5 0 0 0 m 1 0 0 0 0 m 1 5 0 0 0 m 2 0 0 0 0 m
ATC (Atmospheric Transfert Coefficient) = Trajectory of the pollutant cloud
Case of AZF
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
DiagnosticsDiagnostics
• Budget (heat, momentum, microphysics species, Budget (heat, momentum, microphysics species, TKE) with masksTKE) with masks
• Diagnostic fields Diagnostic fields • Lagrangian trajectories Lagrangian trajectories (3 added prognostic fields) (3 added prognostic fields)
• Passive tracersPassive tracers• Comparison to observations Comparison to observations (Meso-NH tools : (Meso-NH tools :
Presentation of I.Mallet-N.Asencio)Presentation of I.Mallet-N.Asencio)
http://www.aero.obs-mip.fr/mesonh/doc.html/#lagrangian
z=z-z0 after 30min
Orographic convection
17km
270km
Gheusi (2003)
Growing of a convective cell
10km
10km
Total water mixing ratio (vap+liq)Initially at z0=1500m
T=14min
Gheusi (2003)
+ Trajectory/Back-trajectory
Dynamics of a thalweg
Initial height z0 of particles currently at z=7000m
Initial latitude y0 of particles currently at =315K
Exemple obs2mesonh: T2MExemple obs2mesonh: T2M
Ouest Est
Coupe Horizontale K=20
Exemple obs2mesonh: réflectivité radar Exemple obs2mesonh: réflectivité radar RonsardRonsard
Coupe verticale : modèle + radar
dBz
Milan
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
Meso-scale modelling wind climatology
An alternative to the measurement = the meteorological models
Error of the climatology = Error of the model
Measurements at 10m height are used to evaluate the quality of the climatology
First solution An operational numerical weather prediction, with an important record : Aladin 5 ans (resolution 0.1°)
Methodology only for the mean wind speed (not for extreme winds, or another meteorological field)
• First step : Statistical selection of weather patternsClassification of weather patterns on 700hPa geopotential of ECMWF reanalyses (résolution 1°, 15 years) 19
classes, with a weight (occurrence)
Choice of the dates number 95 dates
Choice of the dates : Number of the dates proportional to the frequency
Second solution A mesoscale meteorological model (x=1-3 km), not yet operationnal
• Second step : Simulation of the selected dates with Meso-NH95 dates simulated (24h) with ALADIN initial and coupling fields
Wind climatology build up with the weighted function of each of the 19 weather patterns
Error of the climatology = Error of the model + Error of the statistical sample
Vosges, Forêt Noire : 1.2 km
Alpes du Nord 2 km
Alpes du Sud 2 km
Pourtour méditerranéen 3 km
Auvergne 2 km
Sud-Ouest 3 km
Geographical area with Meso-NH wind climatology
Limousin 1km
Bourgogne 2 km
Quiberon 1 km
Roses Aladin 3 ansMéso-NH 95 dates Measurements
North Alps
Méso-NH 95 dates
77
75
77
74
80
77
France (synop)
Vosges
Alpes du Nord (29 stations)
Alpes du Sud (26 stations)
Massif Central (67 stations)
Sud-Ouest (72 stations)
Méditerranéen (99 stations)
Obs 95 dates
88
92
91
90
88
87
Aladin 3-4 ans
80
72
62
63
69
80
71
Evaluation on Dry Convective boundary layer : CARBOEUROPE
Boundary Layer HeightMESONH vs RS La Cape Sud
0
500
1000
1500
2000
2500
0 500 1000 1500 2000 2500
observed
sim
ula
ted
25-may
26-may
27-may
31-may
06-june
07-june
08-juin
09-juin
10-juin
MESO-NH vs PIPER
La Cape Sud : Comparison Meso-NH/RS of BL height (parcel method) between 6 and 17UTC
Weak overestimation during the afternoon
Weak underestimation during the morning
Forecasts of Meso-NH (8km) in an operational mode during the experiment
Examples of Applications of Examples of Applications of Meso-NHMeso-NH
• General description of Meso-NHGeneral description of Meso-NH• Grid nesting Grid nesting • Clouds representation (explicit convective clouds, Clouds representation (explicit convective clouds,
Sc)Sc)• Cyclones Cyclones • Coupling with the surface Coupling with the surface • Coupling with other models (hydrology, Coupling with other models (hydrology,
dispersion)dispersion)• DiagnosticsDiagnostics• Systematic validations (climatology, real time Systematic validations (climatology, real time
runs)runs)• Towards AROMETowards AROME
AROME : Application of Researh to Operations at MEsoscale
Future non-hydrostatic model 2.5km resolution
Dynamics based on ALADIN-NH (semi-implicite, semi-lagrangian)
Data assimilation ALADIN 3D-VAR
Physics based on Méso-NH : microphysics ICE3, Turbulence 1D, shallow convection, externalised surface
http://www.cnrm.meteo.fr/aladin/aladin2/traceMP/AROMErunMP.html
Arome 60s
Case of Gard, initial Case of Gard, initial bogus bogus
Lame d’eau 12-22 Tu
radar de Nîmes
> 300 mm
Couplage : Aladin 3h Forecasts
MésoNH 4s
304 mm
274 mm
• MésoNH t= 4s , CPU = 24h20
• AROME t =60s, CPU = 2h30
Deep clouds
Cirrus clouds
BL clouds : Cu
Mainly driven by dynamics. Mixed-phase microphysicsGood results with AROME (no excessive W)
Depends on convective systems (anvils). Turbulence ice improves the life cycle. Improvement with tuning of microphysics.
-The CBR scheme enables to produce BL clouds. Countergradient (TOMs) insufficient.Improvement : Mass-Flux (Siebesman and Soares)-Subgrid condensation with ED+MF contribution
Larger cloud fraction. Variety of turbulence and stability profiles - Importance of entrainment. Improvement of Mixing length -Aerosol effects -
Transition to BL clouds. Turbulent mixing dominated by large-eddy transport and entrainment at the top.
Improvement : Countergradient (TOMs) versus EDMF (Siebesman and Soares)
Dry CBL
BL clouds : Sc
Stable BL and transition to neutral BL. Improvement of Mixing length. Microphysics and aerosols.
Fog
Imp
rovem
en
t of
Meso
-NH
ph
ysi
cs f
or
AR
OM
E
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