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A new unified boundary-layer scheme for RACMO: The DualM-TKE scheme. Stephan de Roode with contributions from Geert Lenderink Roel Neggers Reinder Ronda Wim de Rooy Pier Siebesma Bert van Ulft Martin Koehler (ECMWF). EDMF: from fundamental turbulence studies to 3D RACMO simulations.
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A new unified boundary-layer scheme for RACMO: The DualM-TKE scheme Stephan de Roode with contributions from Geert Lenderink Roel Neggers Reinder Ronda Wim de Rooy Pier Siebesma Bert van Ulft Martin Koehler (ECMWF)
EDMF: from fundamental turbulence studies to 3D RACMO simulations Large Eddy Simulation (LES) Models Cloud Resolving Models (CRM) Single Column Mode (SCM)l Versions of Climate Models 3d-Climate Models NWP’s 1. Design dualM-TKE scheme 2. SCM results for Cabauw 3. Outlook Time range for developing new scheme is more than 10 years
The Eddy-Diffusivity Mass-Flux (EDMF) scheme • Nonlocal transport through strong updrafts in clear and cloudy boundary layer by advective Mass Flux (MF) approach • Remaining (local) transport done by an Eddy Diffusivity (ED) approach ED MF
Advantages of EDMF • One updraft model for : dry convective BL, subcloud layer, cloud layer. • No trigger function for moist convection needed • No switching required between moist and dry convection needed • Easy and natural transition to neutral and stable PBL • Possible extension to deep convection Further Reading: Soares et al QJRMS (2004) Siebesma et al JAS (2007) De Rooy and Siebesma Accepted for MWR (2008) Neggers et al (submitted to JAS) Courtesy: Martin Kohler (ECMWF)
Status Status EDMF • ECMWF model : Ready. Running in Test Suite. (Roel Neggers) • RACMO model: Ready. Will be used in next climate scenario runs (Stephan de Roode, Geert Lenderink) • Harmonie: Final checks in Single Column Model mode. 3D tests will start early 2008.(Wim de Rooy, Sylvie Malardel)
Running Single Column Models (SCMs) for the Cabauw column - use RACMO 3D large-scale forcing for 2002-2003 - Run three SCM versions with RACMO 3D forcing ECMWF Cycle 31R1 Cycle 31 with dualM (future ECMWF version) RACMO dualM-TKE - Reset to RACMO3D profiles every 24 hours at 0000 UTC - differences in modeling results are due solely to differences in the turbulent transport schemes
PDF LWP for low clouds only C31-R1 dualM-TKE C31-dualM
Cloud base level PDFs C31-R1 dualM-TKE C31-dualM
Outlook RACMO 3D • dualM-TKE has been implemented in 3D RACMO and is running • - compare cloud statistics with observations (CloudNet, MSG-SEVIRI) • - verify stable boundary layer structure, • e.g. Baas et al. (2008), parameterization test bed Roel Neggers • Simulate Hadley circulation (e.g. EUROCS Pacific case) • Clouds and radiation • - Consider implementation of new ECMWF Cycle 32 Monte-Carlo Independent Column Approximation (McICA) radiation scheme