COSMO Workpackage No First Results on Verification of LMK Test Runs Basing on SYNOP Data Lenz, Claus-Jürgen; Damrath, Ulrich

COSMO Workpackage No Overview survey on LMK test runs performed verification results summary and outlook

COSMO Workpackage No Survey on LMK experiments performed (1) - center of model area 10° E, 50° N x 461 grid points horizontally - grid length: 2.8 km - 50 vertical layers, height of lowest layer: 40 m, height of lowest half level: 22 m above ground - values for initialisation and boundaries from operational LM run

COSMO Workpackage No Survey on LMK experiments performed (2) testsuites performed for winter (Januar 2004)

COSMO Workpackage No Survey on LMK experiments performed (3) testsuites for summer (July 2004) und autumn (September 2004) - time integration: TVD Runge-Kutta 3. order, time step: Δt = 30 s - scheme for horizontal advection: upwind 5. order - prognostic calculation of precipitation - thermodynamics: advection of T=T 0 +T* - relaxation at lateral boundaries: explicit formulated cosine function

COSMO Workpackage No LM and LMK: TSS precipitation rates > 0.1 mm/h (top left), > 2 mm/h (top right), > 10 mm/h (left) January 2004, 00 h runs

COSMO Workpackage No Frequency Bias (FBI) for coverage due to low clouds July 2004, 00 h runs cloud coverage <= 2/8 cloud coverage >= 6/8

COSMO Workpackage No Bias (mean error) for 2 m temperature, July 2004, 00 h runs

COSMO Workpackage No LM and LMK: TSS for precipitation rates > 0.1 mm/h (top left), > 2 mm/h (top right), > 10 mm/h (left) September 2004, 00 h runs

COSMO Workpackage No Bias (mean error) for 2 m temperature, September 2004, 00 h runs

COSMO Workpackage No sensitivity of TSS for precipitation with respect to Latent Heat Nudging July 2004, 12 h runs prec. > 0.1 mm/h prec. > 2 mm/h prec. > 10 mm/h

COSMO Workpackage No sensitivity of TSS for precipitation with respect to interpolation method LMK, experiment 701 September 2004, 12 h runs prec. > 0.1 mm/h prec. > 2 mm/h prec. > 10 mm/h

COSMO Workpackage No Summary: - gusts (not shown here): enhanced forecast accuracy in LMK due to finer grid resolution - precipitation: results of the smaller scale model lead to partly better verification results than the LM routine forecast - different tests (e.g. introduction of a parameterization scheme for shallow convection, data assimilation) lead to higher accuracy for some parameters, but other parameters may be affected negatively - interpolation method during verification: higher TSS values at small precipitation rates and lower TSS values at higher precipitation rates using a larger averaging area than the nearest grid point

COSMO Workpackage No Outlook: - further continuous work on verification of past and future LMK experiments - development of a tool for application of conditional verification is ongoing - calculation of synthetic radar images using the radar simulation model by Haase (1998) - verification of LM and LMK using the synthetic radar images