Post on 21-Mar-2016
description
CESI Research
Centre
D.E.A. Università degli studi di Brescia
Mobility and Environmental
Agency of Milan
Toulouse, 5-6/05/2004
Cesare Pertot - Environmental Studies, CESI Milanopertot@cesi.it
D.S.T.A.Università degli studi
Amedeo Avogadro
Modeling SystemModeling System
Topography Land UseECMWF /ARPEGE/ALADIN
Wind, Temperature,geopotential and relative
Hum.profiles
RAMS
CAMxor
TCAM
MOCAGE modelconcentrations
BOUNDY
Initial and boundary conditions
3-dimensional pollutant
Concentrationpatterns
EMISSIONPROCESSOR
ESCOMPTEhourly gridded emissions
Emission fields3D wind and temperature fields
turbulence parameters
VOC profiles
NASA dataozone column
density,turbidity
ARPEGE/ALADINCloud cover and
precipitationfields
CAMx v. 4.03 (Environ International Corporation, Ca)Eulerian photochemical transport and dispersion model
Model DescriptionModel Description
– grid configuration: horizontal - geographical and cartesian projectionsvertical - generic (w is internally computed)nesting allowed
– horizontal advection scheme: Bott (Bott A., 1989) or Piecewise Parabolic Method (PPM) (Colella & Woodward, 1984)
– vertical advection and diffusion scheme: fully implicit– chemical modules:
• gas phase: SAPRC99 / CB-IV and CMC / IEH integrator• Thermod. Equilibrium: ISORROPIA• SOA: SOAP (Strader et al., 1998)
– dry deposition: Resistance scheme– wet deposition: both gas and particle; within and below cloud– Plume in Grid (Pig) submodel implemented
Model DescriptionModel DescriptionTCAM• transport and deposition:
– terrain-following coordinates system– variable vertical spacing– advection-diffusion scheme (Chapeau function)– resistance-based dry deposition algorithm
• chemical module:– lumped molecule approach (SAPRC-90, SAPRC-97, COCOH-97)– lumped structure approach (CBIV-90)
• aerosol module: fixed moving approach– condensation/evaporation– termodynamic equilibrium – nucleation– acqueous chemistry
• numerical integrator: qssa, Implicit-Explicit Hybrid (IEH)• time resolution: one-hour temporal resolution• wet deposition: yes
MeteorologyMeteorology
– prognostic model based on:• nonhydrostatic, compressible equations of atmospheric dynamics and
thermodynamics• conservation equations (water vapor, liquid and ice hydrometeor mixing
rateos)
– may operate from global to sub-microscale scale (Two-way interactive nesting)– includes:
• parameterisations accounting for turbolent diffusion, solar/terrestrial radiation, moist processes, kinematic terrain effects, cumulus convection (Weissbluth), sensible/latent heat fluxes
• LEAF-2 model (John Lee) storage and vertical exchange of water and energy in multiple soil layers
• TOPMODEL, hydrology model based on Darcy Law for lateral downslope transport
• automatic seasonal variation of SST and vegetation parameters– allows parallel computation on a MIMD computer architecture
RAMS v.4.4 (Colorado State Univ. - ASTER Div. of Mission Res. Corp.)Regional Atmospheric Modeling System
Model configurationModel configuration
ESCOMPTE free run - IOP2 - from 21/06 to 26/06– 3 nested grids:
• 30 km cell size, covering the whole France• 10 km cell size• 3,3 km cell size covering Escompte domain
– input data: 3D six-hourly ECMWF analysis fields– no data assimilation– convective analysis performed only on largest grid– nudging performed only on boundary and top domain
Results - wind field (50 m a.g.l.)Results - wind field (50 m a.g.l.)
• Sea/land breeze regimes• Terrain features effects
Results - wind field (500 m a.g.l.)Results - wind field (500 m a.g.l.)
• Synoptic wind rotation
Results - temperature field (50 m a.g.l.)Results - temperature field (50 m a.g.l.)
• strong temperature gradients at coastal boundaries• influence of Camargue
Comparisons - Temperature Profiles - RS IMKComparisons - Temperature Profiles - RS IMK• Good agreement between obs. And mod. profiles• Good agreement between obs. and SST data during nighttime, differencies during day time• Inversion even during daytime in RAMS profile over water
Comparisons - Wind Speed Profiles - RS IMKComparisons - Wind Speed Profiles - RS IMK
• Wind variability correctly reproduced • Overestimation of WS in lower levels in some cases
Comparisons - Wind Dir. Profiles - RS IMKComparisons - Wind Dir. Profiles - RS IMK
Comparisons - Profiles - RS 4MComparisons - Profiles - RS 4M
• Over land ground temperature correctly reproduced