1. JANUARY 12, 2016 DENVER 2011 MPE PRELIMINARY OZONE MODEL EVALUATION FOR THE DENVER 2011 4 KM BASE CASE RAMBOLL ENVIRON AND ALPINE GEOPHYSICS JANUARY 12, 2016 IWDW/WAQS TECHNICAL COMMITTEE MEETING FORT COLLINS, COLORADO 1

2. JANUARY 12, 2016 DENVER 2011 MPE PRELIMINARY CAMx MAY-AUG 2011 4KM MPE CONCLUSIONS CAMx ozone performance worst in May and best in July & August 2011 (June variable) o Mainly ozone underestimation during May and early June Peak observed ozone concentrations underestimated o For example, 104 ppb @ RFNO on June 24 (model = 76 ppb)  Fairly typical as average inputs (4 km meteorology and average emissions) are provided so model has difficulty in simulating extreme events  Of key monitors, RFNO, NREL and FTCW reasonably good, CHAT worse performing Ozone model performance at top 10 modeled ozone days: Bias usually ≤±10% and almost always ≤±20% (CHAT worst performing) o FY ozone Design Value projection sensitivity analysis substituting poorly performing days may be warranted at some sites 2017 ozone Design Value projections using EPA default assumptions estimates exceedances at CHAT (77.6 ppb) and RFNO (76.0 ppb) o Ozone projections at CHAT based on several poor performing days, additional diagnsotc9 analysis performed to try to understand and improve ozone predictions at CHAT 2

3. JANUARY 12, 2016 DENVER 2011 MPE DENVER 2017 OZONE SIP MODELING -- BACKGROUND Denver Metropolitan Area (DMA) and North Front Range (NFR) region fail to attain the March 2008 0.075 ppm (75 ppb) ozone NAAQS The DMA/NFR must prepare a State Implementation Plan (SIP) that demonstrates the area will attain the ozone NAAQS by 2017 The Denver Regional Air Quality Council (RAQC) is the lead agency for the Denver ozone SIP CDPHE/APCD also heavily involved Modeling conducted by contracting team of Ramboll Environ and Alpine Geophysics 3

4. JANUARY 12, 2016 DENVER 2011 MPE OVERVIEW OF DENVER 2011B CAMx BASE CASE Use WAQS CAMx 2011b base case modeling data files from IWDW Episode: May-Aug 2011 Domains: o 36/12 km CONUS/WESTUS  Boundary Conditions (BCs) for 36 km CONUS domain from MOZART Global Chemistry Model o 4 km Colorado Domain  One-way grid nesting between 12 and 4 km domains  CAMx 2011b 4 km inputs based on window of WAQS 4 km domain inputs  Run CAMx for 4 km Colorado domain o Also set up CAMx for 36/12/4 km two-way grid nesting for source apportionment modeling in future 4

5. JANUARY 12, 2016 DENVER 2011 MPE DENVER OZONE SIP MODELING – UPDATED EMISSION Use WAQS 2011b emissions (mainly 2011 NEIv2) for all sources but on-road mobile sources o EPA 2011 mobile emissions did not use Colorado-specific fleet distribution or actual RVP and did not account for Denver Inspection and Maintenance (I/M) program Mobile sources based on MOVES2014 and SMOKE-MOVES using WRF Data o Standard SMOKE-MOVES for 4 km Colorado domain outside of NAA  MOVES2014 EF look-up table using Colorado-specific fleet distribution, RVP and other parameters o In Denver Nonattainment Area (NAA) used link-based activity data from DRCOG and NFRMPO  Grid link-based activity data to 4 km grids using OTIS  Treat each 4 km grid as a “pseudo county” and run SMOKE-MOVES with hourly WRF meteorology  Brand new approach for using Traffic Demand Model (TDM) link-level VMT and other data (e.g., start locations) to generate gridded hour-specific on-road mobile source emissions for PGM modeling 5

6. JANUARY 12, 2016 DENVER 2011 MPE DENVER 2017 OZONE SIP MODELING – PRELIMINARY MODEL PERFORMANCE EVALUATION (MPE) Initially focus on ozone model performance within the DMA/NFR NAA o Rely on WAQS MPE for MPE of other species and MPE outside of NAA:  PM, Speciated PM, visibility, deposition Numerous graphical displays of model performance as suggested in EPA guidance (EPA, 2007, 2014) Use historical EPA ozone performance goals (EPA, 1991) to help interpret MPE: o Bias ≤ ±15% o Error ≤ 35% o Not Pass/Fail test, just another tool Overview of MPE across DMA/NFR NAA and May—Aug 2011 modeling period Detailed MPE for 12 multiday day episodes o Includes 25 ozone exceedance days in NAA o Detailed MPE down to individual site Focused ozone MPE for 10 highest modeled DMAX8 ozone days at key sites These are the ozone values used in EPA’s future year Design Value projection procedure (MATS) RFNO, NREL, CHAT and FTCW 6

7. JANUARY 12, 2016 DENVER 2011 MPE DENVER OZONE SIP MODELING – MONITORING NETWORK Monitoring network used in MPE Limited data available at four monitors west of Denver KENO, MTEV, GOLI, ELDO Limited NO and NO 2 data just monitors near downtown No VOC measurements Key ozone monitors with 2009- 2013 ozone DVCs: o CHAT = 80.7 ppb o RFNO = 80.3 ppb o NREL = 78.7 ppb o FTCW = 78.0 ppb 7

8. JANUARY 12, 2016 DENVER 2011 MPE CONCLUSIONS OF DENVER OZONE MODEL EVALUATION Ozone model performance poor in May, best in July-August and end of June Observed highest ozone peaks underestimated o 2011 observed peak DMAX8 ozone of 104 ppb at RFNO on June 24 underestimated by model (76 ppb)  Modeled uses average inputs (e.g., met/emiss) so will not capture extreme events Model performance for 10 highest modeled ozone days fairly good at most sites o Modeled data used to make 2017 ozone projections o Exception to this is Chatfield (CHAT) Cut-OffBiasError EPA Goal--≤±15%≤35% Hourly O 3 None7.7%24.5% Hourly O 3 60 ppb-8.5%13.2% DMAX8 O 3 None5.2%12.8% DMAX8 O 3 60 ppb-3.6%8.9% 8 Summary of ozone Normalized Mean Bias and Error performance statistics for May- Aug 2011 across monitors in DMA/NFR NAA and comparison against EPA’s historical Ozone Performance Goals

9. JANUARY 12, 2016 DENVER 2011 MPE DENVER MODELING – MODEL PERFORMANCE EVALUATION Ozone MPE using the Atmospheric Model Evaluation Tool (AMET) o Scatter Plots and MPE Statistics  Hourly and DMAX8 ozone  With no and 60 ppb observed ozone cut-off o Spatial Plots of Site-Specific Bias, Error and Correlation o Time Series Plots o Soccer Plots  Compares ozone bias and error with ozone performance goals (±15%/35%)  Also includes PM performance goals (±30%/50%) and criteria (±60%/75%) Special attention paid to how model is used to make future year ozone projections following EPA guidance (EPA, 2014) The top 10 modeled DMAX8 ozone days are used to develop Relative Response Factors (RRFs) for projecting current year ozone Design Values (DVC) to future year DVF = DVC x RRF So pay particular attention to DMAX8 ozone MPE at key sites for top 10 modeled days RFNO, CHAT, FTCW & NREL If performance on particular day poor, may want to eliminate that day and add next highest day 9

10. JANUARY 12, 2016 DENVER 2011 MPE TOP 20 HIGHEST MODELED DMAX8 OZONE DAYS AT RFNO Rocky Flats North Monitor (RFNO) o Ranked by 20 highest modeled DMAX8 days o 10 highest observed DMAX8 days in Yellow o Next highest 10 observed days in Blue Top 10 modeled DMAX days include 3 of top 10 observed and 6 of top 20 observed days o 6 of top 10 model high days Bias <±10% o Worst day 0624 with -27.1% bias  Highest observed ozone day of 2011 (104.8 ppb)  Model predicted an ozone exceedance (76.4 ppb) o Three other days with Bias = +10 to +20%  EPA guidance select high modeled days as ozone is more responsive to emission changes 10

11. JANUARY 12, 2016 DENVER 2011 MPE TOP 20 HIGHEST MODELED DMAX8 OZONE DAYS AT CHAT Chatfield (CHAT) Top 10 modeled ozone days overestimation bias of 9.3% to 33.0% o Includes none of the top 20 observed ozone days o Second highest 10 modeled ozone days includes 6 of the highest 20 observed ozone days  Bias from -28.3% to +16.9%  0502 day candidate for replacement  Bias = 33% Obs/Mod = 56/74 ppb  Early May so likely modeled stratospheric intrusion day 11

12. JANUARY 12, 2016 DENVER 2011 MPE TOP 20 HIGHEST MODELED DMAX8 OZONE DAYS AT FTCW Fort Collins West (FTCW) Top 10 highest ozone days include 4 of top 20 observed days o Includes very highest observed day on 0725 (86.0 ppb) o 0819 day candidate for substitution  Bias = 66.7%  0829 good candidate to replace 0819 o Remainder top 10 model days has Bias = - 7.7% to +21.5% 12

13. JANUARY 12, 2016 DENVER 2011 MPE TOP 20 HIGHEST MODELED DMAX8 OZONE DAYS AT NREL National Renewable Energy Laboratory (NREL) Top 10 modeled days includes 4 of highest observed top 20 days o Includes 2 nd highest observed day (86.1 ppb on 0718) o Bias from -11.2% to +41.4% o Top modeled ozone day (86.4 ppb on 0712) has highest Bias (+41.4%)  Other 9 of top 10 highest days has Bias < ±20% Next highest modeled ozone days includes 5 of top 20 observed ozone days including highest (96.9 ppb) with Bias = -24.9% (modeled = 72.8 ppb) 13

14. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 OZONE TIME SERIES MAY-AUG: RFNO AND CHAT 14 RFNO: NMB = 3.3%; NME = 12.0%CHAT: NMB = 2.3%; NME = 13.3%

15. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 OZONE TIME SERIES MAY-AUG: FTCW AND NREL 15 FTCW: NMB = 3.5%; NME = 10.9%NREL: NMB = 3.3%; NME = 13.5%

16. JANUARY 12, 2016 DENVER 2011 MPE HOURLY OZONE PERFORMANCE ACROSS MAY-AUG 2011 NORMALIZED MEAN BIAS (NMB) [GOAL ≤±15%] No Obs Ozone Cut-off 60 ppb Obs Ozone Cut-off 16 Most sites achieve goal. Overestimation at DASH, CAMP, ARVA, FTCO AND BRGG. WELD under. All sites achieve ≤±15% goal

17. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 OZONE PERFORMANCE ACROSS MAY-AUG 2011 NORMALIZED MEAN BIAS (NMB) [GOAL ≤±15%] No Obs Ozone Cut-off60 ppb Ozone Cut-off 17

18. JANUARY 12, 2016 DENVER 2011 MPE HOURLY OZONE MODEL PERFORMANCE ALL SITES AND MAY-AUG 2011 MODELING PERIOD 18

19. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 OZONE MODEL PERFORMANCE ALL SITES AND MAY- AUG 2011 MODELING PERIOD 19

20. JANUARY 12, 2016 DENVER 2011 MPE HOURLY OZONE MPE SOCCER PLOTS WITHOUT (LEFT) AND WITH (RIGHT) 60 PPB OBSERVED OZONE CUT-OFF FOR EACH EPISODE 20 Inner box is ozone ±15%/35% ozone performance goal Next slide repeats this information only blown up

21. JANUARY 12, 2016 DENVER 2011 MPE HOURLY OZONE MPE SOCCER PLOTS WITHOUT (LEFT) AND WITH (RIGHT) 60 PPB OBSERVED OZONE CUT-OFF FOR EACH EPISODE 21

22. JANUARY 12, 2016 DENVER 2011 MPE 22 DMAX8 OZONE MPE SOCCER PLOTS WITHOUT (LEFT) AND WITH (RIGHT) 60 PPB OBSERVED OZONE CUT-OFF FOR EACH EPISODE 22

23. JANUARY 12, 2016 DENVER 2011 MPE JULY 15-19, 2011 EPISODE 5 observed ozone exceedance days 9 monitor/days with top 10 modeled ozone at four key monitors: o 0716 @ FTCW o 0717 @ RFNO, CHAT, FTCW, NREL o 0718 @ RFNO, FTCW, NREL o 0719 @ CHAT 23

24. JANUARY 12, 2016 DENVER 2011 MPE JULY 15-19, 2011 -- HOURLY OZONE 24

25. JANUARY 12, 2016 DENVER 2011 MPE JULY 15-19, 2011 -- DMAX8 OZONE 25

26. JANUARY 12, 2016 DENVER 2011 MPE JULY 15-19, 2011 -- TIME SERIES: RFNO AND CHAT 26

27. JANUARY 12, 2016 DENVER 2011 MPE JULY 15-19, 2011 -- TIME SERIES: FTCW AND NREL 27

28. JANUARY 12, 2016 DENVER 2011 MPE MORE DETAILED DIAGNOSTIC ANALYSIS Sensitivity of 2017 ozone projections to MATS assumptions/inputs o 3x3, 5x3, 7x7 array of 4 km grid cells o Screen out days based on model performance (<5%, < 10%, < 15% etc.) Spatial maps of 2011 and 2017 emissions and DMAX9 ozone and differences Examine EPA’s CAMx 12 km 2017 ozone projections from July NODA Investigate WRF MPE and whether clouds/precipitation are affecting CAMx ozone predictions on high observed ozone days at CHAT o For top 20 observed ozone days at CHAT compare daily precipitation between PRISM and WRF and hourly WRF clouds with satellite observations Re-process WAQS 4 km WRF output using latest WRFCAMx and Kv_Patch Recommend next steps for Denver ozone modeling 28

29. JANUARY 12, 2016 DENVER 2011 MPE 1. JUNE 24, 2011 – OBS = 99.4 PPB; PRED = 71.2 PPB; BIAS = -28.3% 29 PRISM WRF

30. JANUARY 12, 2016 DENVER 2011 MPE 1. JUNE 24, 2011 2PM MDT 30

31. JANUARY 12, 2016 DENVER 2011 MPE 1. JUNE 24, 2011 -- 4 PM MDT 31

32. JANUARY 12, 2016 DENVER 2011 MPE 2. JUNE 7, 2011 – OBS = 84.4 PPB; PRED = 67.2 PPB; BIAS = -20.4% 32

33. JANUARY 12, 2016 DENVER 2011 MPE 2. JUNE 7, 2011 -- 1 PM MDT 33

34. JANUARY 12, 2016 DENVER 2011 MPE 2. JUNE 7, 2011 -- 4 PM MDT 34

35. JANUARY 12, 2016 DENVER 2011 MPE 3. AUGUST 13, 2011 – OBS = 84.0 PPB; PRED = 68.0 PPB; BIAS = -16.0% [overstated precipitation may be contributing to under-prediction] 35

36. JANUARY 12, 2016 DENVER 2011 MPE 3. AUGUST 13, 2011 -- 2 PM MDT 36

37. JANUARY 12, 2016 DENVER 2011 MPE 3. AUGUST 13, 2011 4 PM MDT 37

38. JANUARY 12, 2016 DENVER 2011 MPE REVISED CAMX 2011 BASE CASE WITH REPROCESSED MET CAMx 2011 4 km base case simulation meteorological inputs were prepared by extracting a window of the CAMx 2011b 4 km base case inputs developed by WAQS Revised CAMx 2011 4 km base case reprocessed the WAQS 2011 4 km output using latest WRFCAMx and Kv_patch program to generate new CAMx 4 km inputs and run for July 1-14, 2011 o Purpose: Determine whether CAMx met inputs were prepared as we thought, in particular the vertical mixing (Kv) parameters. Too little vertical mixing may exacerbate NOx control ozone disbenefit effect. Findings: o There are large differences in ozone due to re-processing WRF output with latest WRFCAMx/Kv_Patch  Several updates in both WRFCAMx/Kv_Patch including addition of stratiform clouds o Unexpected result, new CAMx met inputs will affect 2017 ozone projections 38

39. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 AND HOURLY OZONE CHAT NREL 39

40. JANUARY 12, 2016 DENVER 2011 MPE DMAX8 AND HOURLY OZONE FTCW RMNP 40

41. JANUARY 12, 2016 DENVER 2011 MPE 2017 DENVER SIP MODELING: NEXT STEPS (01/12/2016) New CAMx 36/12/4 km meteorological inputs using WAQS WRF output and latest WRFCAMx/Kv_Patch (2011c) Update 2011 and 2017 emissions and SMOKE emissions modeling o Mobile source emission updates including temporal variations in spatial distribution in start emissions o Oil and gas VOC speciation profile xref review Run CAMx 2011c 36/12 km and process for BCs Run CAMx 2011c 4 km and conduct MPE Run CAMx 2017c 36/12 km and 4 km and make new ozone projections Return data to IWDW 41