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Gas & Aerosol boundary conditions to Chimere from GEOS-Chem. With inputs from : Walter Di Nicolantonio and Alessandra Cacciari (CGS/CNR). Boundary Conditions in regional CTMs. TOP. BCs are implemented as concentrations specified at domain edges and trasported inside by winds.
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Gas & Aerosol boundary conditions to Chimere from GEOS-Chem Withinputsfrom: Walter Di Nicolantonio and Alessandra Cacciari (CGS/CNR)
Boundary Conditions in regional CTMs TOP BCs are implemented as concentrations specified at domain edges and trasported inside by winds Domain of the regional model (e.g. Chimere) NORTH Altitude WEST EAST SOUTH Latitude Longitude Gabriele Curci, CETEMPS - U. L'Aquila
Standard BCs to Chimere CTM MONTHLY mean climatologies from global models Gas LMDz-INCA Aerosol GOCART Gabriele Curci, CETEMPS - U. L'Aquila
What is the impact of BCs? • Test: • CTRL = reference run • NOBC = run w/ BC=0 • Results for Ozone: • Influence of BC expands from boudaries to the center in about 10 days • BC contribute to a background of 50-60 ppbv • Importance of BC depends on local photochemistry activity Gabriele Curci, CETEMPS - U. L'Aquila
Using GEOS-Chem hourly output for Chimere Boundary Conditions • GEOS-Chem v. 8-01-02 • GEOS-4, 4°x5° 30 levs • Dust emissions: scheme implemented by Duncan et al. [2007], with DEAD emissions • Saharan emissions reduced by a factor of 3 following Generoso et al. [2008] Gabriele Curci, CETEMPS - U. L'Aquila
Effect of hourly BCs on Chimere O3 EMEP average Chimere w/ Monthly BCs Chimere w/ Hourly BCs Only marginal improvement: Bias +0.3 ppb RMS -0.2 ppb r +0.02 Gabriele Curci, CETEMPS - U. L'Aquila
Anthropogenic vs Natural PM10 in Europe (year 2003) Anthropogenic PM10 Natural/Biogenic PM10 µg/m3 Chimere model results [Curci et al., in preparation] Gabriele Curci, CETEMPS - U. L'Aquila
Saharan dust event July 27-29, 2005MODIS AOT 550 nm 24/07 25/07 26/07 27/07 28/07 29/07 Gabriele Curci, CETEMPS - U. L'Aquila
Saharan dust event July 27-29, 2005Images from SEVIRI/MSG Sequence of RGB images composite with Brightness Temperatures Differences using InfraRed SEVIRI channels (IR 8.7, IR10.8, IR 12.0) : DUST appears Magenta Gabriele Curci, CETEMPS - U. L'Aquila
Saharan dust event July 27-29, 2005GEOS-Chem hourly BCs to CHIMERE Gabriele Curci, CETEMPS - U. L'Aquila
Effect of hourly BCs on Chimere PM10 Comparison with EMEP ground obs Viznar (ES) 03°W Chaumont (CH) 07°E EMEP average 27/07 28/07 29/07 30/07 Chimere w/ std BCs Chimere w/ Monthly BCs Ispra (IT) 09°E Iskrba (SI) 14°E Chimere w/ Daily BCs Chimere w/ Hourly BCs Gabriele Curci, CETEMPS - U. L'Aquila
Conclusions on preliminary results: Regional ozone simulation not really sensitive to BC details Regional PM simulation very sensitive to Saharan dust events interesting to account for “natural” PM10 excedances Follow ups of this work: Comparison with ground data with PM speciation info (e.g. separate contribution from dust) Comparison with AERONET: AOD at other wavelengths? Test higher GEOS-Chem resolution (2°x2.5°) More episodes and statistics on the longer term THANKS FOR YOUR ATTENTION! Gabriele Curci, CETEMPS - U. L'Aquila
Implementation of GEOS-Chem BCs to CHIMERE CTM Hourly or daily GEOS-Chem timeseries gas & aerosol (binary format) GEOS-Chem global CTM ts_YYYYMMDD.bpch ts_YYYYMMDD.bpch ts_YYYYMMDD.bpch ts_YYYYMMDD.bpch If .not. conse-cutive run src/prep/ prep_boun.f90 Chimere pre-processing Hourly Chimere BC at domain edges (netCDF) INI_CONCS.nc BOUN_CONCS.nc FILES Chimere core (Version 2008b) Existing CODE LEGEND New CODE Gabriele Curci, CETEMPS - U. L'Aquila