Chapter 17. France & Northern Spain St. Sernin, Toulouse, France.
( 1) LA CNRS/UPS, Toulouse, France (2) CNRM, Météo-France, Toulouse, France
-
Upload
addison-everett -
Category
Documents
-
view
68 -
download
3
description
Transcript of ( 1) LA CNRS/UPS, Toulouse, France (2) CNRM, Météo-France, Toulouse, France
Evaluation of simulated precipitation fields of some MAP events: sensitivity experiments
and model intercomparison
(1) LA CNRS/UPS, Toulouse, France(2) CNRM, Météo-France, Toulouse, France(3) RPN, Montréal, Canada(4) ISAC, CNR, Bologna, Italy(5) University of L ’Aquila, Italy(6) University of Milano, Italy(7) University of Munich, Germany
E. Richard (1), N. Asencio (2), R. Benoit (3), A. Buzzi (4), R. Ferretti (5), F. Lascaux (1), P. Malguzzi (4), S. Serafin (6), G. Zängl (7), J-F. Georgis (1)
1. Sensitivity experiments based upon Meso-NH
IOP2a 17 September 1999: A short, intense, isolated, convective
event70 mm within 12h
14:0015:0016:0017:0018:0019:0020:0021:0022:0023:0024:00
RADAR Reflectivity Z 2000mRADAR Reflectivity Z 2000m
OBSERVATIONOBSERVATION MESO-NH COMPUTATIONMESO-NH COMPUTATION
The convective system of MAP - IOP 2a (17 September, 1999, hourly time evolution)
Toce Ticino watershed
ECMWF: OP. ANA ECMWF: OP. ANA 19991999
ARPEGE: OP. ANA. 1999ARPEGE: OP. ANA. 1999 ECMWF: REANALYSISECMWF: REANALYSIS
RADAR OBSERVATIONS
ANA. OP. 1999ANA. OP. 1999 REANALYSISREANALYSIS
850hPa water vapor mixing ratio : 17 September 1999 12UTC
IOP 2a
REANA (NO MAP REANA (NO MAP DATA)DATA)
ECMWF: OP. ANA ECMWF: OP. ANA 19991999
ARPEGE: OP. ANA. 1999ARPEGE: OP. ANA. 1999 ECMWF: OP. ANA. ECMWF: OP. ANA. 20022002
ECMWF: REANALYSISECMWF: REANALYSIS
MAP - IOP2A: Intense Convection Strong sensitivity to initial stateLow predictability
RADAR OBSERVATIONS
1. Sensitivity experiments based upon Meso-NHIOP2a 17 September 1999: A short, intense, isolated, convective event70 mm within 12h
2. Model intercomparison : MC2, MM5, MOLOCH,Meso-NHIOP2b 20/21 September 1999:Orographic enhancement of a frontal system 200 mm within 30h
19 Sept. 1999 12:00 20 Sept. 1999 12:00
METEOSAT infrared
The different models:• MESO-NH 10 KM + 2.5 KM• MOLOCH 10 KM + 2 KM• MM5-RE 27 KM + 9 KM + 3 KM• MM5-E1 18 KM + 6 KM + 2 KM• MC2 40 KM + 10 KM +2 KMInitial and boundary conditions from
ECMWF operational analysesFrom 19 Sep. 12 UTC to 20 Sep. 18 UTC(30 hours)
MAP - IOP2B - 19-20 Sep. 1999Intercomparison exercise4 non-hydrostatic models with horizontal resolution of 2 to 3 kmInitialization based upon ECMWF operational analysisAccumulated precipitation from the 19th 15 UTC to the 20th 18UTC
Toce-Ticino watershed
Rain gauges
Time evolution of the mean hourly precipitation rate
Radar
Heidke skill scores as a function of precip. class
1h precip. 27h precip.
Comparison with rain gauge measurements (121 points)
Correlation 1h
Correlation 6h
Correlation 27h
Mean Bias
MESONH 0.33 0.49 0.62 + 28 % MOLOCH 0.31 0.47 0.62 - 22 % MM5-RE 0.27 0.43 0.55 - 16 % MM5-E1 0.37 0.53 0.63 + 28 %
MC2 0.30 0.47 0.63 - 32 %
Conclusion: Two contrasted MAP events !!
IOP 2a
– Meso-NH results indicate a srong sensitivity to the analysis
– The best results are not obtained for the « best analysis »
– What is the part of luck ?– Is this conclusion model dependent?– Ideal test for mesoscale assimilation
experiments.
IOP 2b
– Very good consistency of the accumulated precipitation pattern
– Model results over/under estimate the total precipitation by a factor ranging from +30% to -30%
– The bias may be related to the level of smoothing applied to the model orography
– The accuracy of the model precipitation is rather weak for the hourly rainfall but fairly reasonable for the precipitation accumulated over the 30h time period of the event
– Radar derived precipitation are not yet very accurate
The End !Interested ??
Join the MAP working group on Numerical Modellinghttp://www.aero.obs-mip.fr/map/MAP_wgnum
Model Topography : Dx = 2KM
MC2: Max 3483m
MM5: Max 3979m
Sensitivity to the topography
MAX: 512 mm MAX: 435 mmMEAN: 78 mm MEAN: 74 mm
Heidke skill scores as a function of precip. class
1h precip. 27h precip.
Sensitivity to the topography
Sensitivity to the analysis
ECMWF Op. Analysis MAP Reanalysis
Max: 512 mm Max: 482 mm Mean: 78 mm Mean: 87 mm
Heidke skill scores as a function of precip. class
1h precip. 27h precip.
Sensitivity to the analysis
Time evolution of the correlation coeffecient (wrt rain gauges)
MM5 experiments
Time evolution of the correlation coeffecient (wrt rain gauges)
MM5 experiments
MM5 experiments