Presentation on theme: "GEMS coordinating meeting - Reading - 15 December 2003 Current status of GEMS-Aerosol Olivier Boucher (LOA / CNRS / USTL) + aerosol partners."— Presentation transcript:
GEMS coordinating meeting - Reading - 15 December 2003 Current status of GEMS-Aerosol Olivier Boucher (LOA / CNRS / USTL) + aerosol partners
GEMS coordinating meeting - Reading - 15 December 2003 Rationale * new studies on aerosol effects on health and ecosystems * construction of GMES ==> users - DAEDALUS survey of aerosol users - ESTEC users workshop * Integrated Global Atmospheric Chemistry Observation Strategy (IGACO) presented to IGOS partners European added value Socio-economic benefits Heritage PHOENICS, CREATE-DAEDALUS, BACC_to_BACC
GEMS coordinating meeting - Reading - 15 December 2003 GEMS Threefold objective of GEMS-aerosol: 1/ to provide operational aerosol products for a variety of end-users GMES – Climate Change 2/ to improve weather forecasts is it covered in the call? 3/ to fulfil the needs for aerosol products from the other sub-projects of GEMS a strong justification for an integrated project
GEMS coordinating meeting - Reading - 15 December 2003 Aerosol products are well identified: - aerosol products for end-users (analysis & forecasts) * 4D distribution of atmospheric aerosols at km resolution * aerosol properties for all sorts of atmospheric corrections * concentrations of PM for air pollution related issues * initial and boundary conditions for smaller-scale air quality models * visibility range (e.g., air traffic, tourism) 2 * photosynthetically available radiation (for e.g. CO 2 cycle) * aerosol deposition flux (impact on vegetation, acid rain) - aerosol products for the other sub-projects * aerosol properties for atmospheric corrections (LAND/GG/OCEAN) * photosynthetically available radiation (LAND / OCEAN) * aerosol properties for heterogeneous chemistry (RG) * aerosol properties for photolysis rates (RG) * aerosol deposition flux over the ocean (OCEAN) further aerosol products may be defined during the project.
GEMS coordinating meeting - Reading - 15 December 2003 The bias in the OLR is significant in W. Africa. It is of similar magnitude to the maximum difference in the OLR over deep clouds associated with the ITCZ (but opposite sign). From J. Haywood, MRF, UKMO
GEMS coordinating meeting - Reading - 15 December 2003 Current participations in GEMS-aerosol LOA: direct model, 1D/4D-VAR, satellite data (connection to MODIS), coordination MPI-Hambourg: direct model, natural sources, clouds MRF-UKMO: validation from field campaigns? University of Köln: 4D-VAR FMI: assimilation of fires?, use of aerosol products for regional AG models +ECMWF (integration, 4D-VAR, …)! Small additional participation for | + Real-time fires natural and anthropogenic emissions | (ESA/ESRIN) stratospheric aerosols? | + Prepared dataset + LSCE-aerosol (AEROCOM) | of clear-sky MODIS | radiances
GEMS coordinating meeting - Reading - 15 December 2003 Our practical goal is to implement an aerosol module in the ECMWF model with data assimilation to be run in analysis and forecast modes. * LMDZ-aerosol model (LOA) - aerosols decoupled from the physics prognostic variables, bin scheme - positively evaluated in AEROCOM * ECHAM5 aerosol model (MPI-Hamburg) - more coupling with the physics prognostic variables, modal scheme - more possibility for linking with cloud physics - more in research mode than LMDZ
GEMS coordinating meeting - Reading - 15 December 2003 Description of LMDZ-aerosol Sulfate: DMS, SO 2, sulfate Black Carbon (BC) : Hydrophobic BC, Hydrophilic BC Organic Matter (OM): Hydrophobic BC, Hydrophilic OM Mineral Dust : Sub-micron, Super-micron (on-line parameterization, M. Schulz/Y. Balkanski) Sea-Salt : up to 20 µm in radius at 80% RH, 5 size bins in sub-micronic range; 5 size bins in 1-20 µm range [Monahan, 1986]. Dry deposition through prescribed dry deposition velocities. Constant values for all surfaces except for sulphur species. Sedimentation for super-micronic sea-salt and dust only. Scavenging: In-cloud – treated separately for stratiform and convective precipitation [Giorgi and Chameides, 1986], for all species except hydrophobic BC and OM. Below-cloud – treated separately for stratiform and convective precipitation, for all species. Convective transport: Tiedtke  but a fraction of gases and aerosols released in the environment from the updrafts is scavenged.
GEMS coordinating meeting - Reading - 15 December 2003 LMDZ- MODIS comparison AOD 550 nm)
GEMS coordinating meeting - Reading - 15 December 2003 ECHAM5 (Roeckner et al., in prep.) Size-Dependent Dry- and Wet-Deposition (Ganzeveld et al., 1998; Slinn and Slinn, 1982; Feichter et al., 1996;...) Online emissions of Dust, Sea Salt and DMS (Tegen et al., 2002; Schulz et al., 2002; Kettle and Andreae, 2000;...) Sulfur Chemistry (Feichter et al., 1996) Aerosol Microphysics M7 (Vignati, Wilson, and Stier, in preparation) Nucleation of sulfate particles Condensation of sulfate on existing particles Coagulation Transfer from insoluble to soluble modes Thermodynamic equilibrium with water vapour Cloud Microphysics (Lohmann and Roeckner, 1996; Lohmann et al., 1999; Lohmann and Kärcher, 2002) Radiation Module (Boucher and Stier)
GEMS coordinating meeting - Reading - 15 December 2003 ECHAM5 - Aerosol Representation Resolve aerosol distribution by 7 log-normal modes Each mode is described by three moments: Number, Median Radius Mass, Standard Deviation (fixed) Number of transported tracers to 28 Mixing State: AITKEN (0.005 µm < r < 0.05 µm) ACCUMULATION (0.05 µm < r < 0.5 µm) SOLUBLE / MIXED COARSE (0.5 µm < r ) INSOLUBLE 1 N 1, M SO 4 5 N 5, M BC, M OC 6 N 6, M DU 7 N 7, M DU 2 N 2, M SO 4, M BC, M OC 3 N 3, M SO 4, M BC, M OC, M SS, M DU 4 N 4, M SO 4, M BC, M OC, M SS, M DU NUCLEATION (r < µm) MODES IN M7
GEMS coordinating meeting - Reading - 15 December 2003 Global Aerosol Optical Thickness ( ) ( ) ( )
GEMS coordinating meeting - Reading - 15 December 2003 Volcanic eruptions have a strong impact on AOD Global mean aerosol optical thickness of GACP AVHRR climatology (updated version of Geogdzhayev et al., 2002) El ChichonMt. Pinatubo
GEMS coordinating meeting - Reading - 15 December 2003 Science plan WP1: Aerosol sources Quite some expertise already We still need - better volcanic sources (also real-time) - refined sea-salt and dust emissions - diurnal and weekly cycles of FF emissions - year-to-year variations (trend) in FF emissions - real-time BB emissions (synergy with RG) WP2: Direct model of aerosols Quite some expertise already (PHOENICS heritage) Adaptation to ECMWF model is needed sulfate / BC / OC / sea-salt / dust (nitrate, ammonium, SOA) bin versus modal scheme
GEMS coordinating meeting - Reading - 15 December 2003 Science plan WP3: Data assimilation Quite some experience in aerosol remote sensing We will rely on MODIS, then operational met satellites Issues of data flow to ECMWF Issue of upscaling of satellite data to model resolution AERONET data could be assimilated real-time 1D-VAR then 4D-VAR aerosol products then aerosol radiances? Clear-sky VIS radiances over the ocean (VIS + surface albedo over land) (IR + surface temperature over land) All TL + ADJ codes are being developed
GEMS coordinating meeting - Reading - 15 December 2003 Science plan WP4: Integration (ECMWF) Issues of - satellite data flow - implementation of the different system components - information exchange with other systems - delivery of products through some web interface WP5: Validation of aerosol monitoring system Many aerosol datasets (GAW, EMEP, AERONET,...) Experience of AEROCOM Definition of scores (forecast vs analysis, analysis vs in-situ)
GEMS coordinating meeting - Reading - 15 December 2003 Open issues - how much cloud physics do we put in the sub-project? - relatively little experience of the aerosol community in 4D-VAR : do we start assimilating aerosol products or clear-sky radiances? - how much effort do we put on natural and anthropogenic aerosol sources?
GEMS coordinating meeting - Reading - 15 December 2003
AEROCOM Aerosol model comparison with satellite / AERONET / in-situ measurements PI: Michael Schulz/Stefan Kinne + a dozen groups interested 1996/ /2001 ==> sessions at fall AGU (SF) and next EGU (Nice)