1 / 39

Baton Rouge 8-hr Ozone Modeling Technical Review Meeting

Baton Rouge 8-hr Ozone Modeling Technical Review Meeting . Presentation to the LDEQ/AQSD & 8-hr Ozone SIP Coalition July 27, 2006. Today’s Presentation. Conceptual Model of 8-hr Ozone Episode Analysis Modeling System Modeling Domain Emission Inventory Development Area & Point Sources

palti
Download Presentation

Baton Rouge 8-hr Ozone Modeling Technical Review Meeting

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Baton Rouge 8-hr Ozone ModelingTechnical Review Meeting Presentation to the LDEQ/AQSD & 8-hr Ozone SIP Coalition July 27, 2006

  2. Today’s Presentation • Conceptual Model of 8-hr Ozone • Episode Analysis • Modeling System • Modeling Domain • Emission Inventory Development • Area & Point Sources • Motor Vehicles (on-road & off-road) • Biogenics & Fires

  3. Today’s Presentation • Initial/boundary conditions • Use of Probing Tools

  4. Conceptual Model • Baton Rouge is a Marginal 8-hr Ozone nonattainment area • Single 2003 exceedance DV: • LSU = 86 ppb • Four 2005 exceedance DVs: • LSU = 96 ppb • 2006 exceedances: • Will not attain standard by June 2007 as required

  5. Conceptual Model • Likely “bump-up” to Moderate area • Attainment date: June 2010 • Spatial distribution • Four key exceedance monitors • LSU, Baker, Carville, Port Allen • Aligned south-to-north along river • Other monitors mostly outside & south of Baton Rouge • Likely interaction between urban, industrial, and biogenic emissions

  6. Conceptual Model

  7. Conceptual Model • Temporal distribution • Diurnal: classic 12 – 4 PM peaks • Evidence of ozone cloud transport site to site • No obvious late AM ROFEs or THOEs • Possible early PM ROFEs or THOEs • Weekly: no clear-cut weekday/weekend dependencies – more analysis needed • Seasonal: trends toward late spring, early fall multi-day, multi-site episodes • In last few years, mid-summer episodes are typically 1-day, few sites

  8. Conceptual Model

  9. Conceptual Model • Weather requirements • Stagnation, light/variable winds under high pressure • Exceedances independent of wind direction • Clear skies • Temperatures do not need to be hot • Many exceedances in low 80’s F • Emissions-driven, not heat-driven • Few prolonged hot summer episodes • Excessive PBL venting or Gulf breeze? Recent interannual climate?

  10. Conceptual Model • Regional transport • Needs 2-3 day transport times • Recent summer episodes are too short • Some multi-day episodes are clearly caused by local stagnation, re-circulation • Some multi-day episodes establish consistent transport corridors from midwest, Ohio Valley, south-east U.S. • Choose episodes that represent mix of conditions • Season, meteorology, transport, WE/WD

  11. Episode Analyses • Screened 14 episodes from 2000-2004 • 2005 de-emphasized • Concern about availability of emissions data • Reduced to 6 candidates • Max exceedance monitor-days at 4 key monitors • Min number of modeling days • Different times of year • Recent episodes

  12. Episode Analyses • 6 candidates • May 19-30, 2003 (M, Sa, W, Th) • September 28-30, 2004 (W, Th) • April 12-30, 2003 (Su, M, F, Su, M, Tu) • October 4-6, 2003 (Sa, Su) • May 4-9, 2004 (Tu, W, Th, Sa) • August 11 – September 5, 2000 (F, Su, Th, F, Sa, Su, M, F, Sa, W, Th, F, Sa, Su)

  13. Episode Analyses • Comparison to CART analysis • Bin 10 (22%) • Bin 20 (24%) • Bin 25 (33%) • Bin 27 (10%) • Bin 35 (11%)

  14. Episode Analyses • Final 2-3 episodes need to be selected from 6 candidates • Input from advisory group • Consider schedule, resources, and pre-existing datasets • July 31 draft Protocol documents conceptual model for each of 6 episodes

  15. Episode Analyses

  16. Episode Analyses

  17. Episode Analyses

  18. Episode Analyses

  19. Episode Analyses

  20. Episode Analyses

  21. Modeling System • MM5 – Meteorological Model • Widely used to support regulatory modeling • EPS3 – Emissions Processor • LDEQ is familiar with EPS • CAMx – Air Quality Model • Widely used to support regulatory modeling in south-central U.S. • Full Chemistry PiG allows evaluation of HRVOC plumes

  22. Domain Configuration • Regional grid (36 km) based on TCEQ • Intermediate grid (12 km) captures transport from Midwest and Southeast • Local grid (4 km) along Gulf Coast, including Houston • Vertical grid based on St. Louis modeling

  23. Domain Configuration

  24. Domain Configuration

  25. Domain Configuration

  26. Emission Inventories • Start-point inventories: • 2002 CENRAP Base B • 2002 VISTAS Base G • 2002 MRPO Base K • TCEQ inventories and other datasets • Useful for August/September 2000 episode • Replace CENRAP data for Texas when available for other years?

  27. Emission Inventories • 2000-2005 LDEQ data, as available • Stationary point, area • On-road: VMT, MOBILE6 • Non-road: NONROAD

  28. Emission Inventories • Inventory projections • Specific modeling years (2000-2004, 2009) • Regional: based on RPOs, EPA, and TCEQ • Local: future year projections are challenging due to recent events • EGU and other large sources: • Use CEM as available for base case model performance evaluation • Use “typical” inventory rates for projected base and future years

  29. Emission Inventories • Biogenics from GloBEIS • All grids, episode-day specific • Driven by: • MM5 and/or temperature observations • Satellite PAR data • Land cover/biomass data (GIS, etc.) • Held constant into 2009 future year • Fires (wild, agricultural, prescribed) • As needed, as available

  30. Initial/Boundary Conditions • Only needed on 36-km grid • Use 2002 VISTAS model output fields • Derive monthly-average diurnally-varying IC/BCs for base case episodes • Use 2009 VISTAS model output fields • If available, as described above • Otherwise, use 2002 fields

  31. CAMx Probing Tools • Ozone Source Apportionment Technology (OSAT) • Determines source area/category contribution to ozone anywhere in the domain • Tracks NOx and VOC precursor emissions, ozone production/destruction, and initial/boundary conditions • Estimates ozone production uner NOx- or VOC limited conditions

  32. CAMx Probing Tools • OSAT • HOWEVER: it cannot quantify ozone response to NOx or VOC controls • Chemical allocation methodologies: • OSAT: standard approach • APCA: attributes ozone production to anthropogenic (controllable) sources only • GOAT: tracks ozone based on where it formed, not where precursors were emitted

  33. CAMx Probing Tools • PM Source Apportionment Technology (PSAT) • Parallel to OSAT operation • Tracks user-defined groups of species for sulfate, nitrate, ammonium, SOA, Mercury, and primary PM

  34. CAMx Probing Tools • Decoupled Direct Method (DDM) for sensitivity analysis • Calculates first-order concentration sensitivity to emissions, initial/boundary conditions • Allows estimates of effects of emission changes • Allows ranking of source region/ categories by their importance to ozone formation

  35. CAMx Probing Tools • DDM • Slower than OSAT, but: • Provides information for all species (not just ozone) • More flexible in selecting which parameters to track • Better estimate of small emission perturbation impacts (e.g., control measures) • Includes sensitivity from non-linear secondary effects

  36. CAMx Probing Tools • Process Analysis (PA) • Designed to provide in-depth analyses of all physical and chemical processes operating in model • Operates on user-defined species and any portion of the modeling grid • Appropriate for evaluating base case performance • Recent UNC enhancements

  37. CAMx Probing Tools • PA • Three components: • Integrated Process Rate (IPR): provides detailed process rate information for each physical process (emissions, advection, diffusion, chemistry, deposition) • Integrated Reaction Rate (IRR): provides detailed reaction rate information for all chemical reactions • Chemical Process Analysis (CPA): like IRR, but designed to be more user-friendly and accessible

  38. CAMx Probing Tools • Reactive Tracers (RTRAC) • Tracks multiple independent reactive gas and particle tracers • Tracers operate in parallel to the CAMx host model • Allows for several generations of products • Decay/production uses standard gas-phase mechanism photolysis and oxidants • Can output tracer decay rates to a separate Lagrangian model for “fenceline” dispersion calculations

  39. CAMx Probing Tools • RTRAC • Designed for primarily for air toxics • Assumes RTRAC species have minimal impact on photochemistry • Each tracer can be “tagged” for source apportionment • RTRAC works with IRON PIG • An optional “sampling grid” capability passively samples near-source sub-grid RTRAC surface concentrations within reactive PiG plumes

More Related