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Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Modellistica numerica per la circolazione atmosferica e la dispersione di inquinanti S. Trini Castelli & D. Anfossi (ISAC – CNR) & E. Ferrero (DISTA – UNIPMN) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche M o d e l l i n g ……………. physical models (wind tunnel, water flumes) numerical models (approximate numerical solutions using numerical integration techniques) diagnostic models (no time-tendency terms) mathematical models analytical models (exact analytical solution in simplified conditions) prognostic models (full time-dependent equations) METEOROLOGICAL CIRCULATION MODELS Study of local, regional or global meteorological phenomena Meteorological input for air pollution DISPERSION MODELS Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Purposes and applications meteorological model: description and forecast of atmospheric processes and circulation on different scales (synoptic, mesoscale, local) dispersion model: analysis and forecast of continuous (Industrial plants or areas) and accidental releases (e.g. Chernobyl (long range), Seveso (short range)) environmental impact evaluation “real time” monitoring air concentration and ground deposition estimation measurement nets planning strategies processing for emissions downing Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche LONG RANGE Synoptic and Planetary spatial scale Time scale from weeks to months-years ECMWF ANALYSES driving LONG RANGE DISPERSION MODELS Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche MILORD Chernobyl Method for the Investigation of Long Range Dispersion Lagrangian Particle Stochastic model (D. Anfossi, D. Sacchetti, S. Trini Castelli, 1995) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche MILORD Method for the Investigation of Long Range Dispersion Lagrangian Particle Stochastic model (D. Anfossi, D. Sacchetti, S. Trini Castelli, 1995) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche REGIONAL AND MESOSCALE Spatial scale from few tens to few hundreds km Time scale from few hours to few weeks REGIONAL METEOROLOGICAL MODELS driving REGIONAL/LOCAL DISPERSION MODELS Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche METEOROLOGICAL MODEL Mean Flow Turbulence u j ui uj ui p ui gδ13 2εijk Ω j uk t x j x j xi θ θ 1 u j ρ0 uθ S θ t x j ρ0 x j etc …. Closure u uθ E E E π u j uj uj ui i θ0 uj g i δi 3 t x j x j x j xi θ0 Transport Diffusion DISPERSION MODEL Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche INTERFACING METEOROLOGICAL and DISPERSION MODELS DISPERSION = TRANSPORT (Mean wind) + DIFFUSION (Turbulence) Turbulence characteristics required by air pollution models (Eddy diffusivities, wind velocity variances, Lagrangian time scales) are usually NOT provided directly by meteorological models BUT must be derived from their output using wind and temperature fields and additional fields such as turbulent kinetic energy, turbulent length scale, mixing height, atmospheric surface layer parameters. INTERFACING PARAMETERIZATION SCHEME !!! Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche R M S modelling system Atmospheric circulation model: Boundary layer parameterisation interfacing code: Lagrangian particle dispersion model: RAMS MIRS (Regional Atmospheric Modeling System Pielke et al., 1992) (Method for Interfacing RAMS and SPRAY Trini Castelli and Anfossi, 1997, Trini Castelli, 2000) (Brusasca et al., 1989, Anfossi et al., 1998, SPRAY Tinarelli et al, 2000, Ferrero et al. 2001) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS modelling system RAMS Fields of - WIND, TEMPERATURE, T.K.E., K (3 D) TOPOGRAPHY, SURFACE FLUXES (2 D) MIRS Fields of - WIND, K, SKEWNESS/KURTOSIS, & TL (3 D) TOPOGRAPHY, PBL height (2 D) SPRAY Fields of - PARTICLE POSITIONS G. L. CONCENTRATION Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche MIRS from RAMS fluxes to… Surface layer parameters from Louis (1979) parameterisation u* - u' w' - v' w' 2 2 * - ' w' u* u*2 L gk* z a u U F , Ri R z z u 2 a 2U 2 F m , Ri * z0 B 2 * h * B 0 13 z w u i L Convective velocity scale Gradient Richardson number profile Diffusion coefficient profile PBL height Turbulent kinetic energy profile External datasets Gryning and Batchvarova (1990) simplified - Batchvarova and Gryning (1991) complete model Variances and decorrelation time scales 2 2 1 1 2 v u q 2 w2 1q 2 Coupling with Mellor-Yamada scheme 2 u Coupling with E-l or E- schemes ui2 2 K mi Hanna (1982) and Degrazia et al. (2000) parameterizations Third and fourth moment of the vertical velocity TLui K mi ui2 u 2 E xi 3 TLui 2 ui2 C0ui Chiba (1978), Anfossi(1997) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche SPRAY Lagrangian particle models are three-dimensional models for the simulation of airborne pollutant dispersion, able to account for flow and turbulence space-time variations Emissions in the atmosphere are simulated using a certain number of fictitious particles named ”computer particle”. Each particle represents a specified pollutant mass. It is assumed that particles passively follow the turbulent motion of air masses in which they are, thus it is possible to reconstruct the emitted mass concentration from their space distribution at a particular time In these models the temporal evolution of the velocity particles released in the atmosphere, that is in turbulent conditions, is prescribed by the Langevin equation, where velocity fluctuations are considered a Markov stochastical process du(t ) a( x, u) dt b( x, u) dW t x = particle position; u = particle velocity fluctuation; U = mean wind velocity; dW = stochastic fluctuation ai ( x, u) dt deterministic term with dx U u t dt dW t 0 ; dW 2 t dt bij (x,u)dWi (t ) stochastic term dW j incremental Wiener process Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Examples of R M S applications D Karlsruhe flat neut/unst USA Idaho falls flat low wind USA EPA-RUSVAL hill (wind tunnel) neutral USA EPA-RUSVAL valley (wind tunnel) neutral USA Indianapolis urban all stabilities CH TRANSALP alpine region unstable N Lillestrom flat – snow covered stable DK Copenhagen flat coast unstable D TRACT complex all stabilities I Vado Ligure complex coast all stabilities F Marseille complex coast all stabilities I Turin urban/complex all stabilities BR Cubatão very complex coast all stabilities J Tsukuba and Ohi complex coast all stabilities I Brenner Highway alpine region all stabilities I-F Torino-Lione Highway alpine region all stabilities Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS RibeirãoPires R.G.daSerra TOP TRACT BOT In collaboration with Dr. J Carvalho (ULBRA) ( km) Cubatão SãoVicente Brazil Santos In collaboration with Dr. A. Kerr (USP) SW ( km) The modelling system RMS: RAMS-MIRS-SPRAY SE Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS Courtesy of Running on the highway! In collaboration with Drs. G Brusasca, G. Tinarelli, S. Finardi The modelling system RMS: RAMS-MIRS-SPRAY EPA – RUSVAL wind tunnel experiment RAMS sensitivity to turbulence closure RMS Observed data speed (ms-1) E-l simulation speed (ms-1) MY82 simulation speed (ms-1) Observed data u (ms-1) E-l simulation u (ms-1) MY82 simulation u (ms-1) RMS EPA-RUSVAL: closure scheme effect on dispersion (1) u2 (1 2 )q 2 v2 2w q (2) 2 MY82 closure + (1) + (3) u2i 2 K mi u 2 E xi 3 (3) TLui K mi u2i E-l closure + (2) + (3) Scatter plots of the RMS simulated concentrations against measurements EPA-RUSVAL: concentration distribution Cu hc2 χ Q RMS C is the concentration corrected subtracting the background, Q is the tracer flow rate hc is a convenient length scale of the experiment Cumulative frequency distribution (c.f.d.) of normalized mean concentrations χ. Observed data: solid line; RMS with E-l closure: dotted line; RMS with MY82 closure: dashed line Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche OHI (Japan) nuclear plant site. Testing the effect of alternative turbulence closures (in collaboration with MHI Fluid Dynamics Lab., Dr. Ohba, Dr. Hara) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS TRACT is back! El-ISO El-SMA MY MY-Hanna Testing the effect of alternative turbulence closures also on TRACT (in collaboration also with CESI, Dr. Alessandrini) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS Regional down to local scale Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Wind velocity at 10 m RMS Wind velocity at 150 m Low wind case, September 1999 Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche RMS Foehn case, February 2000 start: 09.02.2000 11 GMT (12 LST) end: 10.02.2000 15 GMT (16 LST) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche SPEED (m/s) 30.06.2000 12:00 TEMPERATURE (K) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche SPEED (m/s) 30.06.2000 18:00 TEMPERATURE (K) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Comparison with observations: time evolution of wind speed and temperature at the surface Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche 31/5/2001 00:00 - 1/6/2001 00:00 (Sicily coast) 3-D particles and g.l. concentrations – hourly imagines Courtesy of Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche NUMBERS AND NUMERICS! RAMS parallel versions 5.0, 6.0 : parallel efficiency 68% — 90 % (Tremback C., personal communication) n. of processors computer hardware model configuration SPRAY versions 3.! : parallelization in process at AriaNet (Brusasca G., Tinarelli G., Finardi S., Morselli M.G.) Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche NUMERICS AND COMPUTERS! Past to present at ISAC-TO AlphaServer DS20E Tru64 Unix microprocessor 21264 - 833MHz CPU (2!) ‘Parallel’ present at DFG-UNITO (Prof. G. Boffetta) 3 Server TYAN GX28 2GB RAM CPU AMD Opteron 244 (2 x 3 = 6) Networking Gb Ethernet ‘Parallel’ next future at ISAC-TO + DFG-UNITO 5 Server TYAN GX28 2GB RAM CPU AMD Opteron 244 (2 x 5 = 10) Networking Myrinet 2000 Fiber Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche Mellor-Yamada 1982 dE E KE Pε dt z z In RAMS Level 2.5: B.L approximation, horizontal homogeneity u 2 v 2 g P K m K h z z z 0 K m S ml (2E) 1 K h S hl (2E) 2 l1, 1, l2 , 2 l A1, B1, A2 , B2 l u u Sm , Sh , S E f , , , E, l , A1, A2 , B1 , B2 , C z z z kz 1 + kz 1 2E 3 2 1 K E S E l (2E) 2 l 0.1 l 1 2 z Edz Edz (A1,A2,B1,B2,C)=(0.92, 16.6, 0.74, 10.1, 0.08) From MIRS to SPRAY u2 (1 2 )q 2 w3 0.6 v2 q 2 2w q 2 TLi *3 w z 0.1 w3 k L From Chiba (1978) Km i2 q 2 2E 1 A 2 1 3 B1 Istituto di Scienze dell’Atmosfera e del Clima - Torino Consiglio Nazionale delle Ricerche E- l isotropic dE E KE Pε dt x j x j In RAMS P uiu j ui x j c E 3 / 2 l δi,3 gαuiθ u u j 2 Eδ i uiuj K m x j xi 3 ij l kz 1 + kz θ uθ K h i x i l 0.1 l K m c μ E 1 / 2l z Edz Edz K h αh K m From MIRS to SPRAY u2 2 K m i ui 2 E xi 3 K E αE K m TLu i Km u2 i 3 w* z w 0.6 0.1 w3 k L 3 (K-theory) From Chiba (1978)