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Presented by Paul Makar , Air Quality Modelling and Integration Unit Environment Canada

www.ec.gc.ca. AURAMS Case Studies: Low Resolution Agricultural, High Resolution Urban, Low Resolution PAH simulations. Presented by Paul Makar , Air Quality Modelling and Integration Unit Environment Canada Contributors: NH 3 : Annie Duhamel, Sophie Cousineau,Veronique Bouchet,

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Presented by Paul Makar , Air Quality Modelling and Integration Unit Environment Canada

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  1. www.ec.gc.ca AURAMS Case Studies: Low Resolution Agricultural, High Resolution Urban, Low Resolution PAH simulations. Presented by Paul Makar, Air Quality Modelling and Integration Unit Environment Canada Contributors: NH3: Annie Duhamel, Sophie Cousineau,Veronique Bouchet, Roxanne Vinzgaran, Colin DiCenzo PrAIRie2005: Brian Wiens, Sunhee Cho, John Liggio, Craig Stroud, Mike Moran, Wanmin Gong, Sunling Gong PAH: Elisabeth Galarneau, Mourad Sassi, Miriam Diamond (U of T) Contact: firstname.lastname@ec.gc.ca

  2. Three Studies • NAESI : National Agro-Environmental Standards Initiative, Air Theme. • Focus: the effects of NH3 on particulate matter formation. • Multi-disciplinary study, Environment Canada in collaboration with Agriculture and Agri-Foods Canada • Air-Theme: overall budget of ~$1.5M/year, 3 years (2007/08 is concluding year). • Monitoring networks • Measurement intensives • Emissions studies • Emissions database • Modelling : Scenarios with old and new NH3 emissions inventories. AURAMS and CMAQ simulations.

  3. Three Studies • PrAIRie2005: Measurement intensive around and over the city of Edmonton, late summer 2005. • 2 instrumented aircraft, 4 instrumented mobile laboratories (3 with Chemistry, one LIDAR). • Comparisons of observations to 21km and nested 3km resolution AURAMS simulations

  4. Three Studies • AURAMS-PAH • Emissions processing system input files modified to estimate PAH emissions relative to total VOC emissions from different sources. • Chemistry and partitioning of PAHs (two methods) added to AURAMS (6 gas-phase species, 6x12 particle bins) • Initial simulations on Continental scale domain will be shown.

  5. NAESI Simulations • What would be the effect of reductions in ammonia emissions on PM2.5 mass in Canada and the USA? • What is the chemistry linking ammonia and PM2.5, and how would it change if ammonia emissions are decreased?

  6. NAESI Simulations • In Canada (and USA), most of the ammonia emissions are related to agricultural activity: 2000 Emissions Inventory! Buyer Beware!

  7. NAESI Simulations – Models Used • AURAMS: • National level scenarios • Continental 42km domain • CMAQ • Regional Case Study, Lower Fraser Valley (Vancouver Area) • 4km resolution (nested)

  8. NAESI Simulations - AURAMS • Using the existing/old inventory, 3 scenarios: • 20% NH3 emission reduction in Canada only • 20% NH3 emission reduction in USA only • 20% NH3 emission reduction in both countries • Compared to Base Case 2002 annual run • Six months for each scenario (June  November, 2002). • More scenarios planned with new inventory

  9. NAESI - Model evaluation against observations PM2.5 ammonia: comparison with obs. : Scatterplots of measured vs. predicted 2002 annual p2.5-NH4 mass (mg/m3, STP) by observing network: Moran, M.D., Q. Zheng, and M. Samaali, 2007. Long-term multi-species performance evaluation of AURAMS for first 2002 annual run. EC internal report, Toronto, Ontario (in preparation).

  10. NAESI Simulations - AURAMS • Example: USA, Canada both reduce NH3 emissions by 20%. • Examine change in: • PM2.5 concentration (mg/m3) • p-NH4 / [ 2 p-SO4 + p-NO3] (mole ratio) • … and several other metrics • Compare June and November 2002

  11. NAESI Simulations - AURAMS June 2002: PM2.5 concentration change with 20% reduction in North American NH3 emissions. Base Case - Scenario Note logarithmic scale Max reduction 3 to 5 ug/m3, Los Angeles. Large scale reductions of > 0.5 ug/m3 in eastern N. America

  12. NAESI Simulations - AURAMS June 2002: PM2.5 concentration percent change with 20% reduction in North American NH3 emissions. Base Case - Scenario Max reduction 15%

  13. NAESI Simulations - AURAMS November 2002: PM2.5 concentration change with 20% reduction in North American NH3 emissions Note logarithmic scale. Max reduction >5 ug/m3, Los Angeles. Large scale reductions of > 1 ug/m3

  14. NAESI Simulations - AURAMS November 2002: PM2.5 concentration percent change with 20% reduction in North American NH3 emissions Max reduction of 65%. Big effect on PM2.5 mass in Canadian Prairies, with reductions of > 50% common. changes on order of 20% in USA. i.e. > 1 ug/m3 is a large part of the total PM2.5 in the Prairies in the winter.

  15. NAESI Simulations - AURAMS • Analysis: What is the simulated particle charge ratio ? June: Base Case p-NH4 /(2 p-SO4 + p-NO3): Note logarithmic scale. Values < 1 are acidic

  16. NAESI Simulations - AURAMS • Analysis: How does the simulated particle charge ratiochange with reductions in NH3 emissions? June: DBase Case p-NH4 /(2 p-SO4 + p-NO3): Note logarithmic scale. Base Case - Scenario shown. A lot of noise! Ratio For scenario is lower over eastern area; particles becoming slightly more acidic, but difference is small. Although the regime shifts towards higher acidity in the west, the particle acidity does not change much.

  17. NAESI Simulations - AURAMS • Analysis: What is the simulated particle charge ratio ? November: Base Case p-NH4 /(2 p-SO4 + p-NO3): Note logarithmic scale. Values < 1 are acidic

  18. NAESI Simulations - AURAMS • Analysis: How does the simulated particle charge ratiochange with reductions in NH3 emissions? Nov: DBase Case p-NH4 /(2 p-SO4 + p-NO3): Base case – scenario Note logarithmic scale. Blue regions: less acidic particles In region of maximum decrease of PM2.5, particles in Prairies are becoming less acidic (!). US midwest: particles becoming slightly more acidic.

  19. NAESI Simulations - AURAMS Summary: • Magnitude of effects is very dependant on season and region. • 20% NH3 emission reduction: PM2.5 decreases by ~0.5 ug/m3 summer, ~1 ug/m3 in the winter. • 20% NH3 emission reduction: PM2.5 decreases by ~10 % summer, but up to 65% in the winter. • Summer: little change in particle acidity. • Winter: much lower particle acidity in Canada, slightly higher in USA.  Need to check out winter particle deposition: could be acid particles are depositing sooner in Canada; smaller size due to less NH4.

  20. NAESI Simulations - CMAQ Colin DiCenzo, Roxanne Vinzgaran et al. • Reduce agricultural ammonia emissions in southern British Columbia – what happens? • Determine the extent of ammonia transport across the British Columbia/USA boundary.

  21. NAESI Simulations - CMAQ • Apply CMAQ over small coastal urban region (Lower Fraser Valley; LFV) at 4km, for a number of emission change scenarios. • Use 2000 emissions inventory. • Meteorology: August 2001 and December 2002. • Produce animations of the model results for ozone, PM2.5, ammonia, nitrogen deposition, & sulphur deposition. • Construct time series plots of visibility along 5 lines of sight.

  22. NAESI Simulations - CMAQ • Local emission changes: - 20 to 100% reductions in agricultural ammonia in steps of 20% (5 scenarios) - 100% increase in agricultural ammonia • Trans-boundary Considerations: - all US anthropogenic emissions turned off - all Canadian anthro emissions turned off

  23. NAESI Simulations - CMAQ Example: 60% reduction in ammonia, change in PM2.5

  24. NAESI Simulations - CMAQ • 60% reduction in NH3 required to see a significant reduction in PM2.5 in this region. • NH3 is not a limiting species in the formation of ammonium sulphate/nitrate aerosols in LFV. • Mole ratio analysis in the LFV indicates that reductions of NOx and SOx may be more effective at reducing PM2.5 than NH3 reductions

  25. PrAIRie2005 – Urban AURAMS • Measurement intensive around and over city of Edmonton, late summer 2005. • Edmonton is “interesting”: second highest number of oil and gas processing facilities in a municipal region in North America (1st is Houston), coal-fired power-plants 60 km upwind of city, oil-sands development farther upwind. • AURAMS used in forecast mode during study, and at higher resolution post-processing

  26. PrAIRie2005 • 4 Measurement Platforms, Ground-Based:

  27. PrAIRie2005 • Measurement Platforms, Aircraft: ~100,000 Euro to modify this aircraft and fly 3 weeks

  28. PrAIRie2005 Modelling, post-campaign: • PBL Investigation: compare model results to observations for different PBL approximations, at high and low resolution. • Emissions study: checking database emissions against observed emissions, model predictions, and aircraft concentration observations • Principal component analysis: Comparisons of model results, aircraft observations and analysis to infer sources.  All results preliminary!

  29. 15 km GEM Output AMPP Interpolation 21 km AURAMS Output 3 km GEM-LAM AMPP Interpolation 3 km AURAMS PrAIRie2005 – Different Resolutions Nesting: • 15 and 2.5 km GEM weather forecast (global/regional and Local Area Model versions), to drive : • 21km and 3 km AURAMS. 6 hourly met analysis (4DVAR)

  30. PrAIRie2005 – Different Resolutions 21km and 3 km AURAMS. 15 minute timestep 2 minute timestep Edmonton

  31. Measured PM1 SO4 (mg/m3), Airborne AMS PrAIRie2005 – Emissions Study Good agreement for timing and location of main features in high res domain. AURAMS-Simulated PM1 SO4 (mg/m3), 3km resolution Images courtesy J. Liggio,EC/ARQP

  32. Fort Saskatchewan Edmonton CRUISER data Courtesy J. Brook Very good agreement for NO, downwind of source region CRUISER

  33. PrAIRie2005 – Different PBL Schemes: weather forecast model modifications Original GEM - Unmodified met model TKE_NEW_R - Met model has heat island added to surface radiative transfer scheme (Makar et al, 2006), and modified TKE formulae for PBL(Han et al 2000). NEWLM - In addition to the TKE_NEW_R changes, a lower limit TKE profile is used (based on Nastrom and Eaton’s observations, 2005). For the high and low resolution runs, how do these sensitivity tests affect model performance both inside and downwind of the city?

  34. PrAIRie2005 – Comparisons with Observations Ground Level O3, downtown Edmonton 21 km AURAMS 3 km AURAMS Peaks tend to be overpredicted. Peaks tend to be underpredicted.

  35. PrAIRie2005 – Comparisons with Observations Ground Level NO, downtown Edmonton 21 km AURAMS 3 km AURAMS Highest amount of Turbulence (pink) gives closest results to obs. (blue) Ditto, but all simulations overpredict NO.

  36. PrAIRie2005 – Comparisons with Observations Ground Level CO, PM2.5, similar behaviour as NO, for downtown Edmonton

  37. PrAIRie2005 – Comparisons with Observations Ground Level NO, 80 km downwind (CRUISER) 21 km AURAMS 3 km AURAMS Clear improvement relative to observations, with the use of the high resolution model

  38. PrAIRie2005 – Comparisons with Observations Ground Level SO2, 80 km downwind 21 km AURAMS 3 km AURAMS Clear improvement relative to observations, with the use of the high resolution model

  39. PrAIRie2005 – Comparisons with Observations Ground Level O3, 80km downwind (CRUISER) 21 km AURAMS 3 km AURAMS Downwind ozone is improved with use of high resolution.

  40. PrAIRie2005 – Comparisons with Observations Ground Level PM1 SO4, 80 km downwind 21 km AURAMS 3 km AURAMS PM1 SO4: Improvement?

  41. PrAIRie2005 – Comparisons with Observations Some conclusions on the resolution issue: Downwind:  Increasing resolution improves model results for many species. In urban core:  Increasing resolution decreases simulation accuracy.  Simple heat island + TKE limits are insufficient to provide the dispersion required to reduce simulated concentrations to match observations.

  42. PrAIRie2005 – Emissions Study Work by post-doc Sunhee Cho: • Studying coal-fired power-plants using AURAMS at high resolution. • Simulations show model overpredicting sulphate relative to airborne AMS observations. • Compared standard emissions input and Continuous Emissions Monitoring – found former was 2x too high, scaled latter. • Compared “before” and “after” scaling simulations against aircraft AMS observations.

  43. PrAIRie2005 – Emissions Study Power-plant Emissions Before, Measured, Scaled: Original Emissions Measured Emissions Scaled Emissions 1000 2000 1000 Average of scaling factors for SO2 and NOx used to scale other emissions

  44. PrAIRie2005 – Emissions Study Effect of Original versus Scaled Emissions: DNOx: max change -30 ppbv DSO2: max change -225 ug/m3 Edmonton city Coal –fired power plants Edmonton city

  45. 10 2 PrAIRie2005 – Emissions Study Effect of Original versus Scaled Emissions: Slope and intercept of PM1 SO4 in plume improved. SO2 halved PM1 SO4 better, still high

  46. PrAIRie2005 – Emissions Study Effect of Original versus Scaled Emissions: • The scaled emissions data are better correlated with CEM data and improve model predictions. • Comparison between simulations shows improvements in predicted concentrations near the coal-fired power plants. • Model comparison with observation results show that using scaled emissions has reduced the difference between model and observation data from a factor of 4.6 to 2.3.

  47. PrAIRie2005 – Advanced Data Processing • Work with John Liggio, Shao-Meng Li • Comparison of regional model results, aircraft observations, advanced data processing techniques, to infer sources. • Can different sources be identified? Maybe…

  48. PrAIRie2005 – Advanced Data Processing • John Liggio: using Principal Component Analysis to analyze the airborne aerosol mass spectrometer measurements.

  49. PrAIRie2005 – Advanced Data Processing • John Liggio: using Principal Component Analysis to analyze the airborne aerosol mass spectrometer measurements. • Component 3, afternoon August 27, 2005 flight: This region, where component 3 tracks the total mass well, and accounts for up to 56 percent of the mass, corresponds to the location of the power-plant plume in the high-resolution model run.

  50. PrAIRie2005 – Advanced Data Processing • Work continues on this – may try other forms of analysis as well (PMF, cluster …)

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