Slide 1

Impact of the Top PBL entrainment on the Shallow Convections : the AMMA and the GEWEX Pacific Cross-section Intercomparisons / GPCI. P. Marquet, Mto-France. CNRM / GMGEC / EAC CNRM Toulouse ( 3 july 2006 ) Slide 2 Introduction / Motivations (1) A) The standard (V3-V4) of ARPEGE / Climate physics, based on : a diagnostic turbulent scheme : TKE-2.0 / Mellor-Yamada (1982) + the moist PDF of Bougeault (1982) + (?) Shallow convection a diagnostic micro-physics (RR = Smith + Cond/Evap = Kessler) a (mainly) Deep convection (Bougeault, 1985) Max(N_conv ; N_strat) and Max(qv_conv ; qv_strat) -> FMR rad. Slide 3 Introduction / Motivations (2) B) There are 2 updated physics : NEW1 & NEW2 The aim : to improve the representation of [ Cb / Cu / Sc ] in GCM Why / Which they are ? : more details in the next slides But people want to know which parts are really importants : If possible, search for applications of selected parts of the (new) Climate physics package (in ARPEGE-NWP, in Meso-NH, ) ? This method has already been used to built NEW2 (EUROCS) : more details in the next slides Slide 4 Introduction / Motivations (3) C) The aim of the presentation : A focus on the impact of a selected process : the Top-PBL En- trainment (TKE scheme) the Shallow (Deep ?) convection ? Applications for 4 selected examples (ARPEGE cy24 & cy25) : SCM EUROCS-Cu case GCM / Pacific Cross-section Inter-compar. (EUROCS & GEWEX) GCM / African Cross-section Inter-compar. (AMMA) SCM GEWEX RICO-composite Slide 5 Validation of N_low (N_conv. < Flux_condens. ANEBN) Strato CuSlide 6 The Advanced Physics : NEW1 By J. F. Gueremy -> a wish to develop a new convection scheme Old developments : first outside the Climate team, then inside Based on CAPE and w* : first the Deep, then tuning the Shallow A strong need for : a prognostic micro-physics (Smith+Kessler) A need for : an improvement of the Mellor-Yamada (standard) diagnostic TKE + the first tests of the Top-PBL entrainment Slide 7 The Advanced Physics : NEW2 (I have blended it) -> a wish to use a prognostic TKE scheme Old developments : from the thesis of C. Bossuet (1998, in the Climate teamSlide 8 The Advanced Physics : STANDARD / NEW1 / NEW2 STANDARD / V3-V4 NEW1 NEW2 IPCC / Diagnostic Inter Diag+Prog Prognostic TURBDIAG. Mellor-YamadaDIAG. M&YPROGN. / C.B.R. e / t = 0 e / t = 0 e / t = P D moist PDF / Bougeaultmoist PDF / moist PDF / Bougeault Bougeault / Bechtold Micro-PhysDIAG.PROGN.PROGN. Smith/KesslerSmith/KesslerLopez q_liq / q_ice q_liq / q_iceq_cloud / q_rain Shallowin TURB, but why ?Mass-Flux Mass-Flux Convection + Mass-Flux Bougeault ?CAPE / Gueremy CAPE / Gueremy DeepMass-Flux BougeaultMass-FluxMass-Flux ConvectionConvergence of HUCAPE / Gueremy CAPE / Gueremy Top-PBLNO YES YES Entrainment Grenier Grenier Slide 9 The NEW2 turbulent scheme : TKE-CBR TKE-C.B.R. (2000) + B.L. (1989) + Bougeault (1982) & Bechtold (1995) ; with : EPCI+APCI GCM SCM Slide 10 Micro-physics : pdf TKE-C.B.R. (2000) + B.L. (1989) + Bougeault (1982) & Bechtold (1995) Variance of q_cloud : PDF Slide 11 The PDF Observations ? Talk of Teixera at CNRM (jan-2006) Aircraft obs. of variable Q Stratocumulus Gaussian pdf Cumulus Skewed pdf Cumulus and Stratocumulus Double Gaussian Larson et al. 2001 Sc Cu Slide 12 Vertical Diffusion of the Betts variables : _l and q _t Entrainment in ARPEGE-Climat Tenekes (1973) (CEPMMT) Slide 13 Tenekes (1973) (CEPMMT) Diff.Vert. _l et q _t Entrainment in ARPEGE-Climat Grenier (ARPEGE) Slide 14 SCM / EUROCS_ARM_Cu (Lenderink) Cloud Cover ARP-NEW2 / L19 + Top PBL ent. LES-KNMI ARP-NEW2 / L19 ARP-STD / L19 Slide 15 SCM / EUROCS_ARM_Cu (Lenderink) q_cloud ARP-NEW2 / L19 + Top PBL ent. LES-KNMI ARP-NEW2 / L19 ARP-STD / L19 Slide 16 SCM / EUROCS_ARM_Cu (Lenderink) THETA ARP-NEW2 / L19 + Top PBL ent. LES-KNMI ARP-NEW2 / L19 ARP-STD / L19 Slide 17 SCM / EUROCS_ARM_Cu (Lenderink) R.H. ARP-NEW2 / L19 + Top PBL ent. LES-KNMI ARP-NEW2 / L19 ARP-STD / L19 Slide 18 Sc/St Cu Cb Equator 1st Cross Section 2nd Cross Section U.S.A GPCI = Gewex Pacific Cross-section Intercomparison GCM runs Arpege / V4.5 : 2 years : 1998 and 2003 10 days of spin-up in June (lost) + JJA every 3 h NEW1 : TKE-GY + -phys-GY + CVGY + LPBLE / or not NEW2 : TKE-CBR + LOPEZ + CVGY + LPBLE / or not Slide 19 Sc/St Cu Cb Equator 1st Cross Section 2nd Cross Section U.S.A (a) I.W.V. (b) L.W.P. (c) C. C. EPCI = Eurocs Pacific Cross-section Intercomparison Slide 20 ArpegeMPI ECMWF JMAMetORACMO HIRLAM KF HIRLAM ST ERA (3-6h) Cloud Cover Slide 21 EPCI = Eurocs Pacific Cross-section Intercomparison Cloud Cover ARPEGE-V3 ANA-ECMWF Met-Office Slide 22 GPCI = Gewex Pacific Cross-section Intercomparison ANA-ECMWF ARP-NEW2 + LPBLE ARP-NEW2 ARP-STD Cloud Cover Slide 23 GPCI = Gewex Pacific Cross-section Intercomparison ARP-NEW2 + LPBLE ARP-NEW2 ANA-ECMWF Cloud Cover Much more realistic results with NEW2 + LPBLE ! 1000 800 900 Slide 24 GPCI = Gewex Pacific Cross-section Intercomparison ARP-NEW2 ARP-STD OMEGA (Pa/s) Much more realistic results with NEW2 ! ARP-NEW2 + LPBLE Slide 25 GPCI = Gewex Pacific Cross-section Intercomparison K6 = ARP-NEW2 V4 = ARP-STD L.W.P. NEW2 much better than STD V4 ! K4 = ARP-NEW2 + LPBLE L.W.P. NEW2 with LPBLE even better ! Slide 26 GPCI = Gewex Pacific Cross-section Intercomparison K6 = ARP-NEW2 V4 = ARP-STD Cloud Cover Less >0 biases with NEW2 K4 = ARP-NEW2 + LPBLE C. C. Less GPCI = Gewex Pacific Cross-section Intercomparison K6 = ARP-NEW2 V4 = ARP-STD No more >0 biases with NEW2 K4 = ARP-NEW2 + LPBLE I.W.V. (b).W.P. May be a