COSMO WG4 activities Oct Sept Pierre Eckert MétéoSuisse WG4 coordinator Interpretation and applications

WP 4.1 COSMO LEPS (development) COSMO LEPS running every day since automn 2002 Test of experimental suites to assess possible modifications of the operational suite. Clustering on 10 members shows better results than using 5 Tiedke and 5 Kain-Fritsch. Simulations for winter storms Lothar and Martin have been performed using ECMWF EPS with moist and operational singular vectors, respectively, and using two different horizontal resolutions (EPS vs. LEPS resolution). Implementation of Brasseur wind gust formulation in SLEPS LM version. Study of the influence of moist SVs and horizontal resolution on the 50 member ensemble forecasts for extreme weather events (with SLEPS). Further development of COSMO-LEPS meteograms Application and validation of the 50 member COSMO-LEPS simulations (SPCOLEPS) with a hydrological model in collaborations with IACETH. Presentations by Andrea Montani and André Walser

COSMO LEPS: meteogram

WP 4.1 COSMO LEPS (verification) The 24h precipitation forecast by COSMO-LEPS has been verified against observations over 3 COSMO countries (Italy, Germany and Switzerland). Different methodologies have been compared: observations against the forecast values interpolated over the station points; comparison of the average and maximum forecast and observed values over boxes of different sizes (0.5 x 0.5, 1.0 x 1.0 and 1.5 x 1.5). Verification has been carried on of the parallel suites, the 5-member Kain- Fritsch one and the 10-member 2-scheme one. Furthermore, the super- ensemble methodology has also been verified. Finally, the precipitation as forecast by ECMWF EPS, both the 5 RMs small EPS and the most recent of the three ensembles on which the system is based has also been verified. A set of test cases has been defined Presentation by Chiara Marsigli

Other EPS studies Multimodel ensemble, superensemble Presentation by Daniele Cane

WP 4.2 Post processing Inventory of postprocessing methods: in progress Spatial and temporal aggregations: Adjustment of Neighbourhood Method (NM) program package to the new high-resolution model LM 2.8 for precipitation. Calculation of Probabilities of Exceedance (and quantiles) for precipitation thresholds with the NM and verification (diverse scores, reliability diagrams) finished for a winter period (Jan 3-17), still in progress for a summer period (July 13-27). Comparison of NM results for LM and LM 2.8. Presentation by Heike Hoffmann Dispersion: Transport of pollutants, Meteorological model is currently running in an operational manner at IMWM, producing almost all necessary input meteo fields required by dispersion model. REMOTA is a dispersion model (DM) that allows simulation of the dispersion of multiple pollutants. The latest addition was an implementation of nitrogen, sulphur and ozone dispersion and transformations. Poster of A. Mazur

WP 4.2 Post processing Trajectories and dispersion modelling A new standard emission scenario ("Core damage without venting") has been introduced, with the isotope Xenon-133 being the main contribution to the radioactive emission and a total emission of 10^15 Bequerel. Presentation and poster by P. Kaufmann.

WP 4.2 Post processing Instability indices Report has been established by A.C. Letestu Try various indices, Boyden, Faust, Showalter,… Also combined indices like SWISS: SWISS=SI WSh (T-Td)600 SI850: Showalterindex WSh3-6 Wind shear 3 -6 km

Instability indices Verification method: aLMo analyses of the summer 2000 Indices are computed for the grid points corresponding to the swiss low altitude stations Predictand: Lightning detected at the station 6 hours before and 6 hours after the analysis.

Instability indices Scores 12z: Index Boyden Faust SWISS CAPE TotalTotals KIndex Humidity SWEAT Surfacelifted Show-alter Deepconvect. Threshold HIT FAR

Aviation applications Documentation on (commercial) applications at DWD. Connection of LM to 1d model (COBEL) in the frame of COST 722 Prediction of turbulence

Turbulence forecast for civil aviation The scope of this project is to make an evaluation of the feasibility and capability of forecasting turbulence using aLMo for civil aviation at MeteoSwiss. Concept and Preliminary Results Sandro Buss

Strategy from observational data  Based on aircraft observations during MAP (Mesoscale Alpine Programm) and high- frequency routine observations on commercial SWISS flights, we seek to objectively determine turbulence severity through the Eddy Diffusion Rate, ε, following ICAO recommendations. Falcon flight on 8th Nov 1999

Strategy from mesoscale simulations  Based on aLMo hindcasts several turbulence diagnostics are compared with the turbulence observations. The diagnostics considered so far are the Brundt Vaisällä frequency, the Richardon number, Ellrod indices, and the Richardson Tendency equation. aLMo Simulation for 8th Nov UTC Richardson Number

WP 4.2 Post processing Diagnose of weather type (ww code) Production of satellite radiances and radar reflectivity Posters by Christian Keil

WP 4.3 Guidelines Guidelines for the use of bench forecasters: Workshop has been organised in Geneva 5-6 May More questions than answers. A proposition will be elaborated by P. Eckert, F. Schubiger, C. Cacciamani, B. Anger. Show the verification results more actively to the forecasters.Get feed back. Collection of forecaster’s feed back. Has been discussed at the same workshop. Organised feed back already exists at DWD, MeteoSwiss