COSMO-SREPS COSMO Priority Project C. Marsigli, A. Montani and T. Paccagnella ARPA-SIM, Bologna, Italy

COSMO-SREPS  COSMO-LEPS (10 km) mainly designed for the 2-5 days range  The spread is coming only from EPS initial and boundary conditions (large scale uncertainties)  COSMO-SREPS (10 km) has been thought as a limited-area ensemble system for the short- range:  add more spread in the short-range => initial and boundary condition from a Multi-Model Multi-Analysis ensemble (INM SREPS)  take into account also small scale uncertainty => limited-area model (LM) errors

Link with data assimilation  1D-Var DA of satellite data to provide retrieval to be nudged within 7km LM (currently carried on by COSMO): investigate the possibility of using COSMO-SREPS to estimate a flow-dependent B matrix  SIR project: COSMO-SREPS will provide boundary conditions for the LM-K ensemble data assimilation runs

limited-area model error: schemes, parameters, surface forcings COSMO-SREPS  i.c. and b.c. perturbations -> INM multi-model multi-analysis  model perturbations -> Lokal Model perturbations LAM ensemble driving model errors analysis error at the global model scale larger scale errors smaller scale errors

ic and bc: multi-model approach  a MUlti-Model MUlti-Boundaries ensemble is operational at INM (Spain): 5 different limited-area models (HIRLAM, HRM, MM5, UM, LM) are nested on 4 different global models (IFS, GME, AVN, UM) => 20 members ensemble (25 km horizontal resolution) IFS LM 25km GME LM 25km AVN LM 25 km Courtesy of INM UM LM 25 km

Good example of inter-consortia collaboration: Formal agreement between COSMO and INM:  LM included into INM SREPS => more members  INM provides the LM-on-SREPS forecasts to COSMO SREPS output made available by INM from May 2006: 3-hourly initial and boundary conditions for COSMO- SREPS are provided daily at ECMWF on ECFS (4 LM runs at 25 km on an Euro-Atlantic area, nested on 4 different global models interpolated with int2lm at 10 km over the COSMO-LEPS area)

Perturbation of model trajectories Schemes (physics and numerics): Some schemes have been selected to be perturbed: Tiedtke, Tiedtke with cape closure, Kain-Fritsch, 2-time-level, Runge-Kutta Parameters: a first selection of the parameters has been done new tuneable parameters will be tested (provided by the COSMO physics people + new namelist) Surface forcings: possible cooperation with Luca Bonaventura to test a technique for the perturbation of surface parameters + exploration of methodologies to perturb initial conditions at high resolution

Parameter list

COSMO-SREPS (Short-Range Ensemble Prediction System) short range (up to 3 days) 16 LM runs at 10 km LM at 25 km on IFS IFS – ECMWF global by INM Spain LM at 25 km on GME GME – DWD global LM at 25 km on UM UM – UKMO global LM at 25 km on NCEP AVN – NCEP global P1: conv. scheme (KF) P2: turb. parameter 1 P3: time filter P4: turb. parameter 2

13 15 UTC

47N 44N 6W9W

13 18 UTC

47N 45N 7W 10W

14 00 UTC

46.5N 45N 10.5W13W

14 06 UTC

13 May UTC COSMO-SREPS PROB. MAPS fc. range h COSMO-LEPS PROB. MAPS fc. range h > 10mm/6h

COSMO-SREPS fc. range May 0-6 UTC ecmwf gme avn ukmo

ensemble spread 12/05 12UTC 13/05 00UTC 13/05 12UTC

member behaviour (“father”)

intra-group distance

1-month test: autumn LM runs at 10 km LM at 25 km on IFS IFS – ECMWF global by INM Spain LM at 25 km on GME GME – DWD global LM at 25 km on UM UM – UKMO global LM at 25 km on NCEP AVN – NCEP global P1: control (ope) P2: conv. scheme (KF) P3: turb. parameter 1 P4: turb. parameter 2

1-month test: model pert. with the same father 10 LM runs at 10 km LM at 25 km on IFS IFS – ECMWF global by INM Spain P1: control (ope) P2: conv. scheme (KF) P3: turb. parameter 1 P4: turb. parameter 2 P5: …

Future plans run of COSMO-SREPS with model perturbations for 1 month of Autumn 2006: statistical analysis of the system provide b.c. for EELMK (DWD) tests comparison with COSMO-LEPS and PEPS test a flow-dependent B-matrix for 1D-Var of satellite data MAP D-PHASE testing period (summer-autumn 2007) : perturbations selected on the basis of the 1-month test verification -> availability of observations comparison with the other available mesoscale ensemble systems