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Causes of Haze Assessment (COHA) Update

Causes of Haze Assessment (COHA) Update. Current and near-future Major Tasks. Visibility trends analysis Assess meteorological representativeness of 2002 (modeling base year) PMF modeling and case study Evaluate winds used in back-trajectory analysis. Trends Analysis Pages - Done.

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Causes of Haze Assessment (COHA) Update

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  1. Causes of Haze Assessment (COHA) Update

  2. Current and near-future Major Tasks • Visibility trends analysis • Assess meteorological representativeness of 2002 (modeling base year) • PMF modeling and case study • Evaluate winds used in back-trajectory analysis

  3. Trends Analysis Pages - Done Are there any statistically significant multi year trends in the haze levels and causes of haze? http://coha.dri.edu/web/general/tools_trendanaly.html • National maps and tables • Individual site analysis

  4. Trends Analysis for Aerosol Light Extinction Coefficients (1/Mm) in 20% Worst Days

  5. Meteorological Representativeness of 2002- Backtrajectory Analysis • Generate 8-day back-trajectories of all WRAP IMPROVE aerosol monitoring sites (every 3 hrs, from 3 starting heights) for 2003 and 2004 to give 5 years of trajectories - 80% Done, will be done by October. • Produce residence time maps for 2002 and the 5-year period (2000 – 2004), plus maps of ratios and of differences of 2002 and the 5-year period for each site. Interpret the maps for each monitoring site and document on the COHA web site – Will be done by November

  6. GRCA2 difference and ratio in residence time between 2002 and the 5-yr period 2000 to 2004 Ratio Map Difference Map

  7. Receptor Modeling - Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) • Mathematical technique for determining the contributions of various sources to a given sample of air SPij – Source Profile: Emissions of compound i from source j (100%). Ij – Contribution of source j (mg/m3). Ci – Concentration of compound i (mg/m3).

  8. Receptor Modeling - Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB) (Cont.)

  9. Positive Matrix Factorization for Groups of Sites Using 2000 – 2004 Aerosol Data Ready to go. Waiting for 2004 aerosol data, will be finished in ~1 month once data are available Grouping of Class I areas by TSSA source region attribution of sulfate and nitrate – 22 groups including Hawaii and Alaska

  10. PMF Running Parameters • Running Mode: Robust Mode, the value of outlier threshold distance = 4.0 (i.e. if the residue exceeds 4 times of the standard deviation, a measured value is considered outlier). • Error Mode (decides the standard deviation of the data): EM = -12 (based on observed value) • FPEAK and FKEY Matrix (controls the rotation) – default: 0 (central), may try different numbers

  11. PMF Input Data – Data Value and Uncertainty • 2000 -2004 aerosol PM10 and PM2.5 mass and chemical speciation data from the VIEWS web site (Al data are excluded due to the large uncertainties in measurements). • Data are screened to remove the days when either PM10 or PM2.5 mass concentration is missing. • Data value and associated uncertainty If data is missing Then data value = geometric mean of the measured values uncertainty = 4 * geometric mean of the measured values Else if data bellows detection limit data value = 1/2 * detection limit uncertainty = 5/6 * detection limit Else data value = measured data uncertainty = analytical uncertainty + 1/3 * detection limit

  12. PMF Output • Source profiles

  13. PMF Output (Cont.) • Contributions of each source to aerosol mass and light extinction for each sampling day mg/m3

  14. Other Planned Work (FY06) • Case study for selected sites: PMF modeling for individual sites • Compare PMF results for the selected sites based on group modeling and individual modeling • Compare PMF smoke factor contribution with 2002 fire emissions inventory and DRI fire database • Combine PMF modeling results with the backtrajectories and emission inventories to investigate the major source regions of certain aerosol sources (e.g. smoke) for each site • Episode analysis based on PMF results

  15. Other Planned Work (FY06) cont. • Redo aerosol composition statistics using 2000-2004 baseline period? • Evaluate winds used in back-trajectory calculations- Measurement data for evaluation collected- Evaluation done by December or so • Prepare overview page for each site: list of products available for the site

  16. Comparison of Source Factors Based on PMF Modeling for AGTI1 and Group 6 (AGTI1, JOSH1, PINN1, PORE1, RAFA1, SAGA1, SAGO1)

  17. Comparison of Factor Contributions to AGTI1 PM2.5 Based on PMF Individual and Group Modeling mg/m3

  18. Backtrajectory Analysis for PMF Factor - Example Backtrajectory analysis for PMF modeled factor 5 (BWS5) (Weighted – Unweighted). This serves to confirm that the factor 5 is in actual fact a “vegetative burn” factor from wildfires to the northwest of Boundary Waters Canoe Area IMPROVE site (Engelbrecht et al., 2004).

  19. Causes of haze questions- 1. What are the aerosol components responsible for haze? – Aerosol summary for 5 baseline period 2. What is the role of meteorology in the causes of haze? – Baktrajectory analysis of transport, difference of 2002 from 2000-2004 average, episode analysis 3. What are the emissions sources responsible for haze? – PMF analysis, off-shore shipping analysis, dust analysis, fire analysis, EI data comparison 4. Are there any detectable and/or statistically significant multi-year trends in the causes of haze? – Trend analysis already completed

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