COSMO WG4 activities Oct. 2003-Sept. 2004

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

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 likeSWISS:

SWISS=SI850 + 0.4 WSh3-6 + 0.1(T-Td)600SI850: Showalterindex WSh3-6 Wind shear 3 -6 km

Instability indices

Verification method:

aLMo analyses of the summer 2000Indices 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

Bo

yden

Fau

st

SW

ISS

CA

PE

To

tal

To

tals

KInd

ex

Hu

mid

ity

SW

EA

T

Su

rface

lifted

Sh

ow

-alter

Deep

con

vect.

Threshold 96 2 0.6 500 47 26 20 3 100 0 18

HIT 46 56 98 94 55 86 34 69 74 95 85

FAR 72 67 76 75 53 60 84 72 67 75 71

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.

3/53/2)( PSD

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 1999 13 UTCRichardson 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 2004. 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