Advances in Science and Research www.adv-sci-res.net 1992-0628 1992-0636 3 8th EMS Annual Meeting and 7th European Conference on Applied Climatology 2008 2009 10.5194/asr-3-79-2009 http://www.adv-sci-res.net/3/79/2009/ http://www.adv-sci-res.net/3/79/2009/asr-3-79-2009.html http://www.adv-sci-res.net/3/79/2009/asr-3-79-2009.pdf 79 84 2009-04-29 Deriving turbulence characteristics from the COSMO numerical weather prediction model for dispersion applications B. Szintai balazs.szintai@meteoswiss.ch P. Kaufmann M. W. Rotach Federal Office of Meteorology and Climatology MeteoSwiss, Zürich, Switzerland At MeteoSwiss an integrated modelling system is used to simulate the dispersion of radioactive material in emergency situations. For the prediction of the atmospheric flow, the COSMO numerical weather prediction model is used. The model is run operationally at 6.6 and 2.2 km horizontal resolution, respectively and uses a 1.5 order turbulence closure with a prognostic equation for turbulent kinetic energy. Both versions of the COSMO model are coupled off-line with a Lagrangian particle dispersion model (LPDM). The aim of this study is to investigate the sensitivity of the dispersion model to different interfacing approaches between LPDM and the COSMO model. The diagnosed turbulence variables are validated on an ideal convective case and two measurement campaigns. Simulations of hypothetical pollutant releases show that the different interfacing approaches can lead to substantial changes in the forecasted concentrations. Arpagaus, M.: Verification of vertical profiles: Operational verification at MeteoSwiss, COSMO Newsletter No. 5., 102–105, available online: http://www.cosmo-model.org, 2005. Batchvarova, E. and Gryning, S. E.: Applied model for the growth of the daytime mixed layer, Bound.-Lay. Meteorol. 56, 261–274, 1991. Beyrich, F. and Mengelkamp, H. T.: Evaporation over a Heterogeneous Land Surface: EVA_GRIPS and the LITFASS-2003 Experiment – An Overview, Bound.-Lay. Meteorol., 121, 5–32, 2006. Buzzi, M., Rotach, M. W., Raschendorfer, M., and Holtslag, A. A. M.: Evaluation of the COSMO-SC boundary layer scheme for stable conditions, Meteorol. Z., submitted, 2009. Doms, G. and Schaettler, U.: The nonhydrostatic limited-area model LM – Part I: Dynamics and Numerics. Scientific Documentation, Deutscher Wetterdienst, Offenbach, Germany, available online: http://www.cosmo-model.org, 2002. Glaab, H., Fay B., and Jacobsen, I.: Evaluation of the emergency dispersion model at the Deutscher Wetterdienst using ETEX data, Atmos. Environ., 32, 4359–4366, 1998. Hanna, S. R.: Applications in air pollution modeling, in: Atmospheric Turbulence and Air Pollution Modelling, edited by: Nieuwstadt, F. T. M. and van Dop, H., D Reidel Publishing Company, Dordrecht, Holland, 275–310, 1982. Kaufmann, P.: Verification of aLMo with SYNOP and GPS data over Europe, COSMO Newsletter No. 5., 113–117, available online: http://www.cosmo-model.org, 2005. Mellor, G. L. and Yamada, T.: Development of a turbulence closure model for geophysical flow problems, Rev. Geophys. Space Phys., 20, 851–875, 1982. Mironov, D. V., Gryanik, V. M., Moeng, C.-H., Olbers, D. J., and Warncke, T. H.: Vertical turbulence structure and second-moment budgets in convection with rotation: A large-eddy simulation study, Q. J. Roy. Meteor. Soc., 126, 477–515, 2000. Legg, B. J. and Raupach, M.: Markov-chain simulation of particle dispersion in inhomogeneous flows: the mean drift velocity induced by a gradient in Eulerian velocity variance, Bound.-Lay. Meteorol., 24, 3–13, 1982. Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461–2474, 2005. Szintai, B. and Kaufmann, P.: TKE as a measure of turbulence, COSMO Newsletter No. 8., 2–10, available online: http://www.cosmo-model.org, 2008. Thomson, D. J.: Criteria for the selection of stochastic models of particle trajectories in turbulent flows, J. Fluid Mech., 180, 529–556, 1987. Zilitinkevich, S., Esau, I., and Baklanov, A.: Further comments on the equilibrium height of neutral and stable planetary boundary layers, Q. J. Roy. Meteor. Soc., 133, 265–271, 2007.