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www.ec.gc.ca. AURAMS : Application and Evaluation on the Regional Scale. Wanmin Gong et al. Air Quality Research Division Science and Technology Branch Environment Canada. OUTLINE. Brief description of AURAMS Recent science-related applications on regional scale:
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www.ec.gc.ca AURAMS : Application and Evaluation on the Regional Scale Wanmin Gong et al. Air Quality Research Division Science and Technology Branch Environment Canada
OUTLINE • Brief description of AURAMS • Recent science-related applications on regional scale: ICARTT 2004 simulation (short-term application) 2002 annual simulation (long-term application) AURAMS-CMAQ inter-comparison • Recent and on-going policy applications Contributors: ARQI/S&TB: M. Moran, P. Makar, C. Stroud, S. Gong, J. Zhang, Q. Zheng, B. Pabla AQMAG/MSC: V. Bouchet, S. Cousineau, M. Samaali, M. Sassi, R. Pavlovic, H. Landry, A. Duhamel, D. Talbot, S. Gaudreault, J. Racine National Research Council of Canada: W. Jiang, S. Smyth et al.
AUnified Regional Air-quality Modelling System • Episodic, regional, size-resolved, chemically-characterized PM modelling system • “Unified’ in sense that it considers multiple air pollutants and can be applied to multiple AQ issues (e.g., PM, acid deposition, tropospheric O3) for integrated AQ management • Consists of 3 main components: • regional emissions processing system (SMOKE); • Canadian weather forecast model (GEM); • “off-line” sectional PM regional air-quality model • Current PM resolution: 12 size bins (0.01-40.96 m) and 9 chemical components (SO4=, NO3-, NH4+, BC, pOC, sOC, CM, SS, H2O) • Similar in terms of science and complexity to EPA’s CMAQ system
AURAMS National Emission Inventories (Cdn, U.S., Mex.) Population data Econometric data Land-use data Geophysical data Meteorological observations (OA) GEM/GEM-LAM (prognostic meteorological model) SMOKE point mobile area on-line biogenic emission Regional PM Model (CTM) Advection/diffusion (of 30 gaseous and 9x12 aerosol tracers) , emission (including gaseous precursors and size-segregated and chemically-resolved PM), dry deposition of gaseous tracer, coupled gaseous, aqueous-phase, aerosol/heterogeneous chemistry, secondary organic aerosol formation, aerosol microphysics (nucleation, condensation/evaporation, coagulation,CCN activation), size-dependentscavenging/wet deposition, size-dependent dry deposition of aerosols, gravitational settling/sedimentation. Components of Smog and Acid Rain: O3, SO2, NOx, etc., speciated PM2.5, PM10, dry & wet deposition of acidifying compounds…
Recent science-related applications on regional scale • Real-time model forecast for flight planning and guidance in recent field measurement campaign (e.g., ICARTT 2004, PrAIRie 2005, TexAQS/GoMACCS 2006). • Post field campaign model simulations, comparison with network and field intensive data (e.g. Pacific 2001, ICARTT 2004, and PrAIRie 2005). • Long-term simulation and model evaluation for the year 2002 • Model intercomparison (e.g., ICARTT 2004, TexAQS/GoMACCS 2006, NRCC AURAMS-CMAQ comparative model performance evaluation).
ICARTT 2004International Consortium for Atmospheric Research on Transport and Transformation EC component focused on chemical transformation and transport by clouds and transport to the Maritimes; 23 flights. • Real-time: forecast and flight planning support for the MSC ICARTT component based at Cleveland; real-time AQ model intercomparison, ensemble forecast, and evaluation (Stu McKeen NOAA/ESRL) • Post field campaign: model evaluation and sensitivity studies : biogenic emission, anthropogenic emission (inventory year and changes due to US NOx SIP Call control), vertical diffusion, horizontal resolution, in-cloud oxidation, SOA formation algorithms. • Evaluation data: AIRNow (O3, PM2.5), IMPROVE (organic/carbonaceous aerosol component), Convair 580, NOAA WP-3, RV Ron Brown, IONS ozonesonde.
ICARTT AQFM ensemble and evaluation [McKeen et al., JGR, 112, D10S20, doi:10.1029/2006JD007608, 2007; McKeen et al., JGR, 110, D21307, doi:10.1029/2005JD005858, 2005]
Selected AIRNOW sites ICARTT model evaluationtime series (42 vs. 15-km resolution)
Comparison with Convair measurement (gases) Flight 16 Flight 17
Comparison with Convair measurement (aerosol sulfate) SU25 Flight 16 Flight 17
ICARTT 2004 model application summary • Ensemble always outperforms any individual members. • Significant impact on ozone prediction from biogenic emission. • Higher resolution (15-km) in general increases the diurnal range of ozone and seems to better capture some of the PM event compared to lower resolution (42-km). • Further model process evaluation making use the extensive measurement data collected during the field campaign (e.g., cloud-aerosol interaction, SOA formation). • Assessing the impact of cloud processing of gases and particles over eastern NA and in its outflow during ICARTT 2004.
2002 annual simulation • Evaluating AURAMS capability to simulate a full 12 month period in support of integrated management of multi-pollutants issues – O3, PM2.5, acid deposition. • Annual run set-up: • Meteorology: GEM 24-km • Emissions: 2000 Canadian/ 2001 US /1999 Mexican + Canadian oil sands included • Forest fire inventory not included • Biogenics on-line with BEIS3v0.9/BELD3 • Continental domain, 42km res. GEM24 -- greyAURAMS42 -- Blue
Evaluation of AURAMS 2002 annual simulation [Moran, M.D., Q. Zheng, and M. Samaali, 2007. Environment Canada internal report, in preparation.] Sulphur:
Evaluation of AURAMS 2002 annual simulation [Moran, M.D., Q. Zheng, and M. Samaali, 2007. Environment Canada internal report, in preparation.] Nitrate: The over-prediction of nitrate (nitric acid, particularly) is partly due to a ~50% overestimation in NO emission for this run.
Evaluation of AURAMS 2002 annual simulation [Moran, M.D., Q. Zheng, and M. Samaali, 2007. Environment Canada internal report, in preparation.] Precipitation chemistry: GEM prognostic precipitation
AURAMS predicted total (wet + dry) deposition for 2002(in H+ charge equivalent/hectare/year) [Zheng and Moran] t-N t-S t-S+N t-S : the sum of SO2, H2SO4, and p-SO4 t-N : the sum of t-NO3, t-NH3, NO2, and PAN t-NO3 : the sum of HNO3, RNO3, and p-NO3 t-NH3 : the sum of NH3 and p-NH4 t-S+N : the sum of t-S and t-N
AURAMS predicted critical-load exceedance for 2002 for Canada Critical-load exceedances for 2002, t-S only Combined aquatic and terrestrial critical-load field for Canada in H+ equivalents/hectares/yr Critical-load exceedances for 2002, t-S+N
Annual run evaluation summary • The evaluation of model performance at seasonal and annual scales is very encouraging, particularly for the acidifying compounds. • The model predicted critical-load (CL) exceedance fields are in broad agreement with the corresponding CL exceedance fields calculated based on measurements.
AURAMS-CMAQ comparative performance evaluation [Smyth, S.C., W. Jiang, H. Roth, and F. Yang, 2007, NRCC/ICPET Report, PET-1572-07S] • Both models were run in their native states; • Common meteorology – GEM15; • Common anthropogenic EIs (2000/2001) and common emissions processing system (SMOKE); • Similar horizontal resolution (but different projections); • Differences : • Vertical resolution; • Processing of meteorological fields; • Biogenic emission processing; • Speciation of primary PM emission; • Model science/algorithms; • Initial and lateral boundary conditions.
Model-to-model comparison : ozone, p-SO4, p-NO3 Max. O3 Avg. p-SO4
Model-to-model comparison : PM composition AURAMS (no sea-salt) CMAQ Avg. PM2.5 conc. (μg m-3) : CMAQ - 1.89 AURAMS - 0.87 (excl. sea-salt) Average PM2.5 composition over land grid cells
NRCC AURAMS-CMAQ comparison summary • Ozone : similar error but different sign. • PM: both model significantly under predict with CMAQ prediction higher than AURAMS’. • Similar spatial distributions between the two models in ozone and PM mass predictions. • An attempt to compare the two models with minimum differences in model input and resolution, but the difference in LBC is seen to impact the inter-comparison significantly. • Needs follow up on the preliminary comparative evaluation.
AURAMS applications to support policy development (Contact: V. Bouchet, AQMAG/MSC, Veronique.Bouchet@ec.gc.ca) • Transboundary transport, e.g., analysis of the impacts of U.S. Clean Air Interstate Rule (CAIR) on future Canadian smog and acid deposition levels; NOx & SOx emission trading – Canada-U.S. emission cap and trade feasibility study. • Sulphur Emission Control Area (SECA) : analyse effects of marine emissions and potential controls on ambient air quality. • Sectoral modelling : scenario modelling of transportation sector and effect on PM; effects of NH3 emissions and potential NH3 emission reductions on ambient air quality. • CARA (Clean Air Regulatory Agenda) support: provide strategic advice in the development of air pollutant emission targets and support in development and implementation of regulations and objectives – scenario runs to provide O3 changes (seasonal to annual), annual PM2.5, seasonal to annual visibility, annual sulphate and nitrate deposition. • Contribution to climate change and health vulnerability assessment (2007): provide estimates of changes in O3 exceedences under higher air temperature conditions. • Contribution to Canadian 2008 smog science assessment.
2015 Business as Usual examples Mean summer (JJA) PM2.5 levels (top) and winter (JFM) PM2.5 levels (bottom) (µg/m3)– BAU - Average summer (JJA) O3 8h daily max (ppb) – BAU -
2002 and 2015 Business as usual examples Averaged visual range (JJA) in km – 2015 BAU Annual SO4= and NO3- wet deposition totals (umoles/m2/yr) for 2015
On-going model development • K-F sub-grid-scale convective tracer mixing • SMOKE treatment of PM speciation and size distribution • Development/implementation of enhanced biogenics emission module • Development and implementation of wind-blown dust emission • Forest fire emission module? • Update gas-phase chemical mechanism and SOA algorithm • Implementation and testing new aerosol activation schemes • Cloud processing of gases and aerosols for cold season • Plume-in-grid module • PAH in AURAMS • Improved treatment of ageing process and mixing state of transport-related aerosols
Major Point Source Emissions Flux Dry Deposition Velocities Calculated Semi- Lagrangian Advection Wind Correction Vertical Diffusion Particle micro-phys. + Cloud Processes + In. Het. Chem. Inside AURAMS’ CTM (Processes) One-step Operator Splitting: (Finite Diff., Area Emissions, Gas Deposition as lower flux B.C.) (Mass Consistency) (Gas + Aerosol) (2nd Order Int. + Global Mass Correction) (Plume rise and vertical distribution of plume) Gas-Phase Chemistry, SOA formation (Aerosol Activation, Aqueous Chem., cloud/precipitation scavenging, evaporation ) (Nucleation + Condensation, Coagulation, Dry Dep.) ( ISORROPIA and HETV {vectorized SO4 - NO3 - NH4} ) (ADOM-II Mechanism, Odum or Jiang SOA approach Post processing (12 size bins; SO4=, NO3-, NH4+, BC, pOC, sOC, CM, SS, H2O)
SO2 oxidation (in-cloud & clear air) – SO2-CO ratio • Both model and observation show a decrease in SO2-to-CO ratio downwind, an indication of SO2 oxidation, but the oxidation seems stronger in model (could be from either or both in-cloud and clear-air oxidation)