Appendix J

Model Performance Evaluation 
Model Performance Evaluation i 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 
Model Performance Evaluation ii 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Table of Contents 

Table of Contents............................................................................................................................ ii 

List of Figures................................................................................................................................. ii 

List of Tables ................................................................................................................................ vii 

1 Air Quality Modeling.................................................................................................................. 1 

1.1 Air Quality Model Configuration ........................................................................................ 1 

1.2 Secondary Organic Aerosols Modifications........................................................................ 2 

2 Model Performance Statistics ...................................................................................................... 3 

2.1 12km Domain Statistics – Selected Regions ....................................................................... 5 

2.2 Metrolina Nonattainment Area and Monitor Statistics........................................................ 6 

3 Spatial Plots ................................................................................................................................ 8 

4 Scatter Plots .............................................................................................................................. 40 

4.1 12km Domain Scatter Plots – VISTAS/ASIP States Only................................................ 40 

4.2 12km Domain Scatter Plots – North Carolina ................................................................... 46 

4.3 12km Domain Scatter Plots – South Carolina ................................................................... 52 

4.4 Metrolina Monitor Specific Scatter Plots .......................................................................... 58 

5 Time Series ............................................................................................................................... 67 

5.1 12 km Domain Time Series Plots – VISTAS/ASIP States Only....................................... 67 

5.2 12 km Domain Time Series Plots – North Carolina .......................................................... 73 

5.3 12 km Domain Time Series Plots – South Carolina .......................................................... 79 

5.4 Metrolina Monitor Specific Time Series Plots .................................................................. 85 

List of Figures 

Figure 1-1 CMAQ nested 12 km grid in the CMAQ 36 km grid. Lower left x, y of the 36 km 

grid is at -2736000, -20880000............................................................................................... 2 

Figure 3-1 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For May 24, 2002 ..................................................................... 9 

Figure 3-2 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For May 25, 2002 ................................................................... 10 

Figure 3-3 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For May 26, 2002 ................................................................... 11 

Figure 3-4 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 1, 2002 ..................................................................... 12 

Figure 3-5 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 2, 2002 ..................................................................... 13 

Figure 3-6 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 3, 2002 ..................................................................... 14 

Figure 3-7 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 9, 2002 ..................................................................... 15 

Figure 3-8 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 10, 2002 ................................................................... 16 
Model Performance Evaluation iii 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-9 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 11, 2002 ................................................................... 17 

Figure 3-10 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 12, 2002 ................................................................... 18 

Figure 3-11 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For June 13, 2002 ................................................................... 19 

Figure 3-12 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 1, 2002 ...................................................................... 20 

Figure 3-13 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 2, 2002 ...................................................................... 21 

Figure 3-14 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 3, 2002 ...................................................................... 22 

Figure 3-15 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 4, 2002 ...................................................................... 23 

Figure 3-16 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 5, 2002 ...................................................................... 24 

Figure 3-17 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 6, 2002 ...................................................................... 25 

Figure 3-18 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 8, 2002 ...................................................................... 26 

Figure 3-19 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 9, 2002 ...................................................................... 27 

Figure 3-20 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 16, 2002 .................................................................... 28 

Figure 3-21 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 17, 2002 .................................................................... 29 

Figure 3-22 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 18, 2002 .................................................................... 30 

Figure 3-23 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For July 21, 2002 .................................................................... 31 

Figure 3-24 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 1, 2002 ................................................................. 32 

Figure 3-25 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 2, 2002 ................................................................. 33 

Figure 3-26 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 5, 2002 ................................................................. 34 

Figure 3-27 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 10, 2002 ............................................................... 35 

Figure 3-28 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 11, 2002 ............................................................... 36 

Figure 3-29 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 12, 2002 ............................................................... 37 
Model Performance Evaluation iv 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-30 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 21, 2002 ............................................................... 38 

Figure 3-31 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) Ozone 

Concentrations Spatial Plots For August 23, 2002 ............................................................... 39 

Figure 4.1-1 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For May............................................................................................................ 41 

Figure 4.1-2 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For June............................................................................................................ 42 

Figure 4.1-3 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For July ............................................................................................................ 43 

Figure 4.1-4 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For August ....................................................................................................... 44 

Figure 4.1-5 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For September.................................................................................................. 45

Figure 4.2-1 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

May ....................................................................................................................................... 47 

Figure 4.2-2 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

June ....................................................................................................................................... 48 

Figure 4.2-3 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

July........................................................................................................................................ 49 

Figure 4.2-4 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

August ................................................................................................................................... 50 

Figure 4.2-5 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

September ............................................................................................................................. 51 

Figure 4.3-1 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

May ....................................................................................................................................... 53 

Figure 4.3-2 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

June ....................................................................................................................................... 54 

Figure 4.3-3 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

July........................................................................................................................................ 55 

Figure 4.3-4 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

August ................................................................................................................................... 56 

Figure 4.3-5 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter Plots For 

September ............................................................................................................................. 57 

Figure 4.4-1 Arrowood 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 59 

Figure 4.4-2 County Line 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 60 

Figure 4.4-3 Crouse 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 61 

Figure 4.4-4 Garinger 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 62 
Model Performance Evaluation v 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.4-5 Enochville 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 63 

Figure 4.4-6 Monroe 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 64 

Figure 4.4-7 Rockwell 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 65 

Figure 4.4-8 York, SC 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September ............................................................................................................................. 66 

Figure 5.1-1 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For May ................................................................................................... 68 

Figure 5.1-2 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For June ................................................................................................... 69

Figure 5.1-3 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For July .................................................................................................... 70 

Figure 5.1-4 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For August ............................................................................................... 71 

Figure 5.1-5 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For September.......................................................................................... 72 

Figure 5.2-1 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For May........................................................................................................................ 74 

Figure 5.2-2 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For June........................................................................................................................ 75 

Figure 5.2-3 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For July ........................................................................................................................ 76 

Figure 5.2-4 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For August ................................................................................................................... 77 

Figure 5.2-5 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For September.............................................................................................................. 78 

Figure 5.3-1 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For May........................................................................................................................ 80 

Figure 5.3-2 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For June........................................................................................................................ 81 

Figure 5.3-3 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For July ........................................................................................................................ 82 

Figure 5.3-4 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For August ................................................................................................................... 83 

Figure 5.3-5 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time Series 

Plots For September.............................................................................................................. 84 

Figure 5.4.1-1 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For May .......... 86 

Figure 5.4.1-2 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For June .......... 87 

Figure 5.4.1-3 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For July........... 88 

Figure 5.4.1-4 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For August...... 89 
Model Performance Evaluation vi 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 5.4.1-5 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For September 90 

Figure 5.4.2-1 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For May....... 91 

Figure 5.4.2-2 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For June....... 92 

Figure 5.4.2-3 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For July ....... 93 

Figure 5.4.2-4 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For August .. 94 

Figure 5.4.2-5 County Line1-hour (top) And 8-hour (bottom) Time Series Plots For September

............................................................................................................................................... 95 

Figure 5.4.3-1 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For May ............... 96 

Figure 5.4.3-2 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For June ............... 97 

Figure 5.4.3-3 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For July................ 98 

Figure 5.4.3-4 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For August ........... 99 

Figure 5.4.3-5 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For September.... 100 

Figure 5.4.4-1 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For May ....... 101 

Figure 5.4.4-2 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For June ....... 102 

Figure 5.4.4-3 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For July........ 103 

Figure 5.4.4-4 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For August ... 104 

Figure 5.4.4-5 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For September

............................................................................................................................................. 105 

Figure 5.4.5-1 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For May .......... 106 

Figure 5.4.5-2 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For June .......... 107 

Figure 5.4.5-3 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For July ........... 108 

Figure 5.4.5-4 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For August ...... 109 

Figure 5.4.5-5 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For September. 110 

Figure 5.4.6-1 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For May............ 111 

Figure 5.4.6-2 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For June............ 112 

Figure 5.4.6-3 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For July............. 113 

Figure 5.4.6-4 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For August........ 114 

Figure 5.4.6-5 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For September .. 115 

Figure 5.4.7-1 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For May ......... 116 

Figure 5.4.7-2 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For June ......... 117 

Figure 5.4.7-3 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For July.......... 118 

Figure 5.4.7-4 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For August ..... 119 

Figure 5.4.7-5 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For September 120 

Figure 5.4.8-1 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For May.......... 121 

Figure 5.4.8-2 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For June.......... 122 

Figure 5.4.8-3 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For July .......... 123 

Figure 5.4.8-4 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For August ..... 124 

Figure 5.4.8-5 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For September 125 
Model Performance Evaluation vii 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

List of Tables 

Table 1-1 VISTAS/ASIP Phase II Initial CMAQ Model Configuration....................................... 1 

Table 2-1 Statistical Metric Calculations....................................................................................... 4 

Table 2.1-1 12km Domain Model Statistics for 1-Hour Ozone..................................................... 5 

Table 2.1-2 12km Domain Model Statistics for 8-Hour Ozone..................................................... 5 

Table 2.1-2 12km Domain Model Statistics for 8-Hour Ozone..................................................... 6 

Table 2.2-1 Metrolina Region and Monitor Statistics for 1-Hour Ozone...................................... 7 

Table 2.2-2 Metrolina Region and Monitor Statistics for 8-Hour Ozone...................................... 7 
Model Performance Evaluation 1 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

1 Air Quality Modeling 

The air quality modeling for the Charlotte-Gastonia-Rock Hill, NC-SC 8-hour ozone 

nonattainment area (referred to as the Metrolina area) was performed in conjunction with the 

regional haze modeling being done by the Southeast Regional Planning Organization, Visibility 

Improvement State and Tribal Association of the Southeast (VISTAS) and the fine particulate 

matter (PM2.5) and ozone modeling being done by the Association of Southeastern Integrated 

Planning (ASIP). VISTAS and ASIP are run by the ten Southeast states (Alabama, Florida, 

Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee, Virginia and West 

Virginia. Since the regional haze and PM2.5 modeling uses annual simulations and includes an 

intermediate year that is the attainment year required for the Metrolina nonattainment area, the 

North Carolina Division of Air Quality (NCDAQ) decided to use the this modeling for its 

attainment demonstration. 

1.1 Air Quality Model Configuration 

This air quality modeling system used in this State Implementation Plan (SIP) modeling exercise 

was the US Environmental Protection Agency’s (USEPA’s) Models-3/ Community Multiscale 

Air Quality (CMAQ). The configuration of the CMAQ modeling system was chosen based on 

the results of the model sensitivity testing performed in Phase I of the VISTAS/ASIP regional 

haze, fine particulate, and ozone modeling efforts. This configuration of options is identical to 

those used in Phase II of the VISTAS/ASIP projects. The Phase II CMAQ configuration is 

presented in Table 1-1. The 36/12 kilometer (km) horizontal and vertical grid system used in the 

VISTAS/ASIP Phase II modeling is displayed in Figure 1-1. 

Table 1-1 VISTAS/ASIP Phase II Initial CMAQ Model Configuration. 

Model Option Phase II CMAQ Configuration

Model Version Version 4.5 (September 2003) 

Horizontal Resolution 36/12 km 

No. Vertical Layers NZ = 19 

Horizontal Advection PPM 

Vertical Advection PPM 

Horizontal Diffusion Spatially Varying 

Vertical Diffusion KV (Eddy Diffusion) 

Minimum Vertical Diffusivity 1.0 m2/s 

MM5 Configuration Pleim-Xiu/ACM No linkage of 5-day run segments 

MM5 Processing MCIP2.2 Pass Through 

Gas-Phase Chemistry CB4 

Gas-Phase Chemistry Solver MEBI 

Secondary Organic Aerosol SORGAM 

Aqueous-Phase Chemistry RADM 

Aerosol Chemistry AE3/ISORROPIA 

Dry Deposition Pleim-Xiu 

Plume-in-Grid Off 

Initial Concentrations Default with 13-15 day spin-up 

Boundary Conditions 2001 Seasonal GEOS-CHEM 

Emissions 2002 Emissions 
Model Performance Evaluation 2 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 1-1 CMAQ nested 12 km grid in the CMAQ 36 km grid. Lower left x, y of the 

36 km grid is at -2736000, -20880000 

1.2 Secondary Organic Aerosols Modifications 

As a part of the Phase II modeling project, the VISTAS/ASIP air quality modeling contractors 

developed modifications to the Secondary Organic Aerosols (SOA) subroutines inside of the 

CMAQ modeling system to improve modeled particulate matter and visibility performance. 

Since the modeling activities in this SIP exercise took a “one atmosphere” approach identical to 

that of VISTAS/ASIP, the CMAQ SOA modifications are included as part of this ozone 

modeling. 
Model Performance Evaluation 3 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

2 Model Performance Statistics 

To quantify model performance, several statistical measures were calculated and evaluated for 

the VISTAS/ASIP states combined, for North Carolina, for South Carolina, and individually for 

each of the Metrolina area ozone monitors. The statistical measures selected were based on the 

recommendations outlined in section 18.4.1 of the USEPA’s Guidance On The Use Of Models 

And Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, and 

Regional Haze (“Attainment Guidance”). 

The statistical measures were calculated for both 1-hour and 8-hour ozone concentrations and 

based only on the respective portion of the 12km modeling domain. A customary 60 parts per 

billion (ppb) cutoff threshold was applied in the statistical calculations. This cutoff threshold 

prevents very low ozone concentrations from being included in the model performance statistics 

and generally prevents a widely known overnight over prediction of minimal ozone 

concentrations from biasing the performance evaluation of the modeling when ozone 

concentrations are much higher and of the most concern. 

For convenience, these statistical measures or metrics along with a variety of additional 

statistical measures are summarized in Table 2-1. 
Model Performance Evaluation 4 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Table 2-1 Statistical Metric Calculations 

Statistical Measure Shorthand 

Notation 

Mathematical Expression Notes 

Accuracy of Paired 

Peak 

Ap

peak

peak

O

P − O

Coefficient of 

Determination 

 R2

( )( )

∑ ∑

∑

= =

=

− −

⎥

⎦

⎤ ⎢

⎣

⎡ − −

N

i

N

i

i i

N

i

i i

P P O O

P P O O

1 1

2 2

2

1

( ) ( )

Pi= prediction at time and 

 location i; 

Oi = observation at time and 

 location i; 

P = arithmetic average of Pi, 

 i = 1, 2, . . ., N; 

O = arithmetic average of Oi, 

 i = 1, 2, . . ., N; 

Normalized Mean 

Error 

NME 

∑

∑

=

=

−

N

i

i

N

i

i i

O

P O

1

1

Reported as % 

Root Mean Square 

Error 

RMSE 

( ) 2

1

1

1 2

⎥

⎦

⎤ ⎢

⎣

⎡ ∑ − =

N

i

Pi Oi N

Reported as % 

Fractional Gross 

Error 

FError 

∑= +

− N

i i i

i i

P O

P O

N 1

2 Reported as % 

Mean Absolute 

Gross Error 

MAGE ∑=

−

N

i

Pi Oi N 1

1

Mean Normalized 

Gross Error 

MNGE 

∑=

N −

i i

i i

O

P O

N 1

1 Reported as % 

Mean Biased MB ∑( ) =

−

N

i

Pi Oi N 1

1 Reported as concentration 

Mean Normalized 

Bias 

MNB ( ) ∑=

− N

i i

i i

O

P O

N 1

1 Reported as % 

Mean 

Fractionalized Bias 

(Fractional Bias) 

MFB 

∑= ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

+

− N

i i i

i i

P O

P O

N 1

2 Reported as % 

Normalized Mean 

Bias 

NMB ( )

∑

∑

=

=

−

N

i

i

N

i

i i

O

P O

1

1

Reported as % 

Bias Factor BF 

∑= ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ N

i i

i

O

P

N 1

1 Reported as BF:1 or 1:BF or in 

fractional notation (BF/1 or 1/BF) 
Model Performance Evaluation 5 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

2.1 12km Domain Statistics – Selected Regions 

The statistical data calculated for the VISTAS/ASIP region, the North Carolina, and the South 

Carolina portions of the 12-km domain are presented in Tables 2.1-1 for 1-hour ozone and 

Table 2.1-2 for 8-hour ozone. On the whole, all of the statistical measures or metrics were 

within generally accepted ranges for mean bias, mean normalized bias, and mean normalized 

gross error. There was a slight under prediction of 1-hour and 8-hour ozone concentrations. 

This under prediction was noted in all months and across the VISTAS/ASIP states as a whole 

and also individually across North Carolina and across South Carolina. The most noted under 

prediction of ozone was contained in the months of August and September. In these months, the 

mean normalized bias fell slightly below the suggested range of ± 5-15 percent. The NCDAQ 

does not believe this slight under prediction for August and September impacts the overall results 

for this SIP modeling exercise. In all cases, the mean normalized gross error was significantly 

below the 30-35 percent range at the 60 ppb threshold for all regions. These 1-hour and 8-hour 

statistical metrics were used as a first screening of the model performance. 

Table 2.1-1 12km Domain Model Statistics for 1-Hour Ozone 

Region / Month Modeled

Mean (ppb)

Observed

Mean (ppb)

Mean Bias

(ppb)

Mean

Normalized

Bias (%)

Mean

Normalized

Gross Error

(%)

May 62.54 69.08 -6.53 -8.92 13.64

June 63.75 73.45 -9.7 -12.67 15.81

July 64.20 73.70 -9.5 -12.16 16.70

August 62.95 75.35 -12.4 -15.78 18.49

September 62.19 74.68 -12.49 -16.20 18.52

Mean (May-Sept) 63.13 73.25 -10.12 -13.15 16.63

May 64.68 70.24 -5.56 -7.53 12.74

June 63.65 74.39 -10.74 -13.97 15.89

July 64.54 75.51 -10.97 -13.71 16.61

August 62.34 76.92 -14.59 -18.24 19.59

September 59.83 71.64 -11.81 -16.08 18.10

Mean (May-Sept) 63.01 73.74 -10.73 -13.91 16.59

May 64.39 69.37 -4.98 -6.72 11.69

June 62.99 73.33 -10.34 -13.36 15.33

July 61.61 72.73 -11.12 -14.54 16.72

August 61.05 74.13 -13.08 -17.20 18.34

September 62.23 75.24 -13.01 -16.69 18.34

Mean (May-Sept) 62.45 72.96 -10.51 -13.70 16.08

12km ASIP States Combined

North Carolina

South Carolina

1-Hour Model Performance Statistics (BaseG2A - 60 ppb Cutoff)
Model Performance Evaluation 6 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Table 2.1-2 12km Domain Model Statistics for 8-Hour Ozone 

2.2 Metrolina Nonattainment Area and Monitor Statistics 

As a further exploration of modeling performance, specifically in the Metrolina region, similar 

1 hour (Table 2.2-1) and 8-hour (Table 2.2-2) statistical measures were calculated for the region 

as a whole and for each of the ozone monitors in this region. In just the Metrolina region, the 

mean bias, mean normalized bias, and mean normalized gross error were all within 

recommended and accepted ranges. A slight under prediction of 1-hour and 8-hour ozone was 

also observed at this more refined level of analysis and was similar to what was seen at the larger 

state and VISTAS/ASIP region levels. Individual monthly statistics are not presented here due 

to the very limited number of modeled and observed data pairs at just the eight Metrolina ozone 

monitoring sites. Whole season statistics were more representative of how this air quality 

modeling will be applied in the modeled attainment test discussed in Appendix L. Across the 

whole season, the Metrolina region as a whole and all of the ozone monitoring sites had mean 

normalized bias statistics in the suggested ± 5-15 percent range and mean normalized gross error 

statistics in the suggested 30-35 percent range given a 60 ppb threshold. 

Region / Month Modeled

Mean (ppb)

Observed

Mean (ppb)

Mean Bias

(ppb)

Mean

Normalized

Bias (%)

Mean

Normalized

Gross Error

(%)

May 61.26 67.69 -6.44 -8.96 12.47

June 62.62 70.99 -8.37 -11.37 14.02

July 62.73 70.85 -8.12 -10.90 14.74

August 61.33 72.57 -11.24 -14.92 16.98

September 60.81 71.98 -11.17 -14.98 17.07

Mean (May-Sept) 61.75 70.82 -9.07 -12.23 15.06

May 64.06 69.05 -5 -6.86 10.76

June 62.21 71.82 -9.62 -13.03 14.47

July 62.94 72.10 -9.16 -12.09 14.63

August 60.60 73.92 -13.33 -17.40 18.34

September 57.90 69.37 -11.46 -16.11 17.68

Mean (May-Sept) 61.54 71.25 -9.71 -13.10 15.18

May 63.87 67.71 -3.85 -5.31 9.66

June 61.95 70.92 -8.97 -12.10 13.52

July 60.89 70.24 -9.35 -12.73 14.75

August 59.77 71.39 -11.62 -16.03 16.64

September 61.18 72.62 -11.44 -15.22 16.32

Mean (May-Sept) 61.53 70.58 -9.05 -12.28 14.18

North Carolina

South Carolina

12km ASIP States Combined

8-Hour Model Performance Statistics (BaseG2A - 60 ppb Cutoff)
Model Performance Evaluation 7 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Table 2.2-1 Metrolina Region and Monitor Statistics for 1-Hour Ozone 

Table 2.2-2 Metrolina Region and Monitor Statistics for 8-Hour Ozone 

Monitor Site AIRS ID Modeled

Mean (ppb)

Observed

Mean (ppb)

Mean Bias

(ppb)

Mean

Normalized

Bias (%)

Mean

Normalized

Gross Error

(%)

Metrolina Region 65.25 73.50 -8.000 -10.346 13.388

Crouse 37-109-0004 69.0 73.0 -4.0 -5.269 9.860

Garinger 37-119-0041 63.0 74.0 -11.0 -14.249 15.940

Arrowood 37-119-1005 67.0 72.0 -5.0 -5.793 12.300

County Line 37-119-1009 67.0 74.0 -7.0 -8.837 11.894

Rockwell 37-159-0021 65.0 74.0 -9.0 -11.643 13.495

Enochville 37-159-0022 65.0 75.0 -9.0 -11.933 13.774

Monroe 37-179-0003 62.0 73.0 -10.0 -13.721 15.371

York, SC 45-091-0006 64.0 73.0 -9.0 -11.326 14.472

8-Hour Model Performance Statistics (BaseG2A - 60 ppb Cutoff)

Monitor Site AIRS ID Modeled

Mean (ppb)

Observed

Mean (ppb)

Mean Bias

(ppb)

Mean

Normalized

Bias (%)

Mean

Normalized

Gross Error

(%)

Metrolina Region 66.875 75.75 -8.75 -10.716 15.035

Crouse 37-109-0004 69.0 76.0 -6.0 -7.232 12.050

Garinger 37-119-0041 66.0 76.0 -11.0 -13.777 17.861

Arrowood 37-119-1005 69.0 74.0 -5.0 -5.872 14.354

County Line 37-119-1009 69.0 77.0 -8.0 -9.248 13.835

Rockwell 37-159-0021 66.0 76.0 -10.0 -12.223 14.812

Enochville 37-159-0022 68.0 77.0 -9.0 -11.230 14.767

Monroe 37-179-0003 63.0 75.0 -12.0 -14.677 17.048

York, SC 45-091-0006 65.0 75.0 -9.0 -11.471 15.549

1-Hour Model Performance Statistics (BaseG2A - 60 ppb Cutoff)
Model Performance Evaluation 8 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

3 Spatial Plots 

The 12km domain spatial plots of modeled 1-hour and 8-hour maximum ozone concentrations 

for 2002, with the actual ozone observations overlaid are presented in this section. These plots 

are magnified or zoomed with respect to North Carolina. Only the days used in calculating the 

relative reduction factor (RRF) calculation at the Metrolina monitoring sites are presented here. 

The first plot on the page is the 1-hour maximum ozone, followed by the 8-hour maximum ozone 

plot. The color scale moves from lower concentrations in shade of blue to warmer colors for 

higher ozone concentrations. The scale loosely approximated the Air Quality Index (AQI) color 

scale for the 8-hour standard but was set to best demonstrate the gradient of ozone across North 

Carolina and Northern South Carolina, and to best highlight the range of observed ozone 

concentrations. 

Overall, the air quality model does well with the spatial extent of the higher ozone 

concentrations. The model does slightly under-predict the 1-hour max and 8-hour max ozone 

concentration, as was seen in the model performance statistic earlier in this Appendix. The plots 

show North Carolina and South Carolina’s higher ozone concentrations generally coincide with 

the major urbanized areas and with the major highways running through the states. The urban 

core of the city of Charlotte, North Carolina is well represented in the air quality model. This is 

important as the highest monitoring values occur at the urban sites (i.e. Garinger, County Line, 

and Enochville). 
Model Performance Evaluation 9 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-1 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For May 24, 2002 
Model Performance Evaluation 10 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-2 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For May 25, 2002 
Model Performance Evaluation 11 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-3 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For May 26, 2002 
Model Performance Evaluation 12 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-4 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 1, 2002 
Model Performance Evaluation 13 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-5 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 2, 2002 
Model Performance Evaluation 14 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-6 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 3, 2002 
Model Performance Evaluation 15 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-7 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 9, 2002 
Model Performance Evaluation 16 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-8 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 10, 2002 
Model Performance Evaluation 17 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-9 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 11, 2002 
Model Performance Evaluation 18 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-10 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 12, 2002 
Model Performance Evaluation 19 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-11 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For June 13, 2002 
Model Performance Evaluation 20 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-12 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 1, 2002 
Model Performance Evaluation 21 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-13 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 2, 2002 
Model Performance Evaluation 22 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-14 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 3, 2002 
Model Performance Evaluation 23 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-15 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 4, 2002 
Model Performance Evaluation 24 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-16 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 5, 2002 
Model Performance Evaluation 25 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-17 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 6, 2002 
Model Performance Evaluation 26 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-18 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 8, 2002 
Model Performance Evaluation 27 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-19 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 9, 2002 
Model Performance Evaluation 28 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-20 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 16, 2002 
Model Performance Evaluation 29 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-21 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 17, 2002 
Model Performance Evaluation 30 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-22 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 18, 2002 
Model Performance Evaluation 31 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-23 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For July 21, 2002 
Model Performance Evaluation 32 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-24 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 1, 2002 
Model Performance Evaluation 33 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-25 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 2, 2002 
Model Performance Evaluation 34 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-26 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 5, 2002 
Model Performance Evaluation 35 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-27 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 10, 2002 
Model Performance Evaluation 36 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-28 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 11, 2002 
Model Performance Evaluation 37 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-29 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 12, 2002 
Model Performance Evaluation 38 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-30 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 21, 2002 
Model Performance Evaluation 39 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 3-31 Modeled Predicted And Observed Peak 1-hour (top) And 8-hour (bottom) 

Ozone Concentrations Spatial Plots For August 23, 2002 
Model Performance Evaluation 40 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

4 Scatter Plots 

Scatter plots of modeled predicted daily maximum ozone versus observed daily maximum ozone 

are presented in this section. There are scatter plots for both 1-hour and 8-hour ozone 

concentrations. As with the previous model performance statistics, scatter plots were created for 

the VISTAS/ASIP region of the 12km modeling domain, for North Carolina, for South Carolina, 

and individually for each of the ozone monitors in the Metrolina region. At the VISTAS/ASIP 

regional and the two individual state levels, monthly scatter plots are presented across the entire 

summer season of May through September. For the individual ozone monitoring sites, only the 

scatter plots for the entire summer season are displayed due to the limited nature of the dataset. 

On each page, the top image is the 1-hour daily maximum ozone scatter plot and the bottom 

image is the 8-hour daily maximum ozone scatter plot for the respective month or season and the 

respective region or monitoring site. 

4.1 12km Domain Scatter Plots – VISTAS/ASIP States Only 

From the whole VISTAS/ASIP region perspective, thousands of data points are presented in the 

1-hour and 8-hour ozone scatter plots (Figure 4.1-1 through Figure 4.1-5). These data points 

include modeled and observed ozone concentrations at numerous urban, suburban, and rural 

ozone monitoring sites. Across this 10 state VISTAS/ASIP region, there are a greater frequency 

of urban and suburban sites represented in these scatter plots. Even with such a wide variety of 

monitoring site locations, the model and observed values tend to correlated reasonable well, as 

most of the data points are clustered along the 1:1 line across the full range of data. The under 

prediction of observed ozone concentrations previously discussed in this Appendix is most 

notable in these scatter plots when observed ozone concentrations are in excess of 120 ppb. 

There are not any systematic abnormalities found in either the 1-hour or 8-hour scatter plots for 

the VISTAS/ASIP region of the 12km modeling domain. This confirms the acceptable model 

performance statistics presented earlier in this Appendix. 
Model Performance Evaluation 41 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.1-1 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For May 
Model Performance Evaluation 42 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.1-2 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For June 
Model Performance Evaluation 43 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.1-3 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For July 
Model Performance Evaluation 44 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.1-4 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For August 
Model Performance Evaluation 45 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.1-5 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Scatter Plots For September 
Model Performance Evaluation 46 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

4.2 12km Domain Scatter Plots – North Carolina 

The 1-hour and 8-hour ozone scatter plots for just North Carolina are presented in this 

subsection. The North Carolina scatter plots for May through September are found in Figure 

4.2-1 through Figure 4.2-5 on the following pages. There is a good mixture of urban, suburban, 

and rural ozone monitoring sites contained in these scatter plots. With this heterogeneous 

mixture of sites, the model and observed values are well correlated and tightly clustered along 

the 1:1 line across the majority of the data pairs. Under predictions of observed ozone can be 

seen when observed ozone concentrations are greater than 100 ppb and are most notable in the 

few cases that observed ozone surpasses 120 ppb. 

There are not any systematic abnormalities found in either the 1-hour or 8-hour scatter plots for 

the North Carolina portion of the 12km modeling domain. This further confirms the reasonable 

model performance statistics presented earlier in this Appendix. 
Model Performance Evaluation 47 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.2-1 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For May 
Model Performance Evaluation 48 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.2-2 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For June 
Model Performance Evaluation 49 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.2-3 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For July 
Model Performance Evaluation 50 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.2-4 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For August 
Model Performance Evaluation 51 

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North Carolina Attainment Demonstration June 15, 2007 

Figure 4.2-5 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For September 
Model Performance Evaluation 52 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

4.3 12km Domain Scatter Plots – South Carolina 

The 1-hour and 8-hour ozone scatter plots for just South Carolina are presented in this 

subsection. The South Carolina scatter plots for May through September are found on the 

following pages (Figure 4.3-1 through Figure 4.3-5). South Carolina has a slightly higher 

frequency of suburban and rural ozone monitoring sites. Even with a lower frequency of urban 

ozone monitoring sites than across the VISTAS/ASIP region or across North Carolina, these 

scatter plots continue to demonstrate very reasonable correlations between model and observed 

ozone concentrations. Under predictions of observed ozone can be seen when observed ozone 

concentrations are at the higher end of the scale, but there are relatively few observations of 

ozone that surpass 120 ppb where more notable under predictions were seen in the previous 

VISTAS/ASIP and North Carolina regional scatter plots. 

There are not any systematic abnormalities found in either the 1-hour or 8-hour scatter plots for 

the South Carolina portion of the 12km modeling domain. This further confirms the reasonable 

model performance statistics presented earlier in this Appendix. 
Model Performance Evaluation 53 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

Figure 4.3-1 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For May 
Model Performance Evaluation 54 

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North Carolina Attainment Demonstration June 15, 2007 

Figure 4.3-2 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For June 
Model Performance Evaluation 55 

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North Carolina Attainment Demonstration June 15, 2007 

Figure 4.3-3 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For July 
Model Performance Evaluation 56 

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North Carolina Attainment Demonstration June 15, 2007 

Figure 4.3-4 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For August 
Model Performance Evaluation 57 

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North Carolina Attainment Demonstration June 15, 2007 

Figure 4.3-5 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Scatter 

Plots For September 
Model Performance Evaluation 58 

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North Carolina Attainment Demonstration June 15, 2007 

4.4 Metrolina Monitor Specific Scatter Plots 

The 1-hour and 8-hour ozone scatter plots for the individual ozone monitoring sites in the 

Metrolina region are presented in this subsection. The Metrolina monitor specific scatter plots 

for the entire summer season of May through September are found in Figure 4.4-1 through 

Figure 4.4-8 on the following pages. Of these 8 monitoring sites, the majority of the sites are 

either urban or suburban. With a more urbanized observed dataset, the respective monitor scatter 

plots show excellent correlation of model and observed ozone concentrations across the entire 

range of data. Under predictions of higher observed ozone concentrations can still be seen in 

these scatter plots, but these under predictions are significantly less notable than in any of the 

previous 1-hour or 8-hour ozone scatter plots presented in this section. 

There are not any systematic abnormalities found in either the 1-hour or 8-hour scatter plots for 

the individual ozone monitoring sites in the Metrolina region. This is a strong indication that the 

model performance statistics presented earlier in this Appendix are sound and that these 

modeling results are appropriate for further use in the modeled attainment test. 
Model Performance Evaluation 59 

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North Carolina Attainment Demonstration June 15, 2007 

1-hour Ozone Scatter Plot - Site: Arrowood

AIRS ID: 37-119-1005

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Arrowood

AIRS ID: 37-119-1005

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-1 Arrowood 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
Model Performance Evaluation 60 

The Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Appendix J 

North Carolina Attainment Demonstration June 15, 2007 

1-hour Ozone Scatter Plot - Site: County Line

AIRS ID: 37-119-1009

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: County Line

AIRS ID: 37-119-1009

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-2 County Line 1-hour (top) And 8-hour (bottom) Scatter Plots For May 

Through September 
Model Performance Evaluation 61 

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1-hour Ozone Scatter Plot - Site: Crouse

AIRS ID: 37-109-0004

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Crouse

AIRS ID: 37-109-0004

0

0.02

0.04

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-3 Crouse 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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1-hour Ozone Scatter Plot - Site: Garinger

AIRS ID: 37-119-0041

0

0.02

0.04

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0.08

0.1

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0 0.02 0.04 0.06 0.08 0.1 0.12

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Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Garinger

AIRS ID: 37-119-0041

0

0.02

0.04

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-4 Garinger 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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1-hour Ozone Scatter Plot - Site: Enochville

AIRS ID: 37-159-0022

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12 Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Enochville

AIRS ID: 37-159-0022

0

0.02

0.04

0.06

0.08

0.1

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-5 Enochville 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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1-hour Ozone Scatter Plot - Site: Monroe

AIRS ID: 37-179-0003

0

0.02

0.04

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Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Monroe

AIRS ID: 37-179-0003

0

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-6 Monroe 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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1-hour Ozone Scatter Plot - Site: Rockwell

AIRS ID: 37-159-0021

0

0.02

0.04

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0.08

0.1

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0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: Rockwell

AIRS ID: 37-159-0021

0

0.02

0.04

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0.08

0.1

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-7 Rockwell 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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1-hour Ozone Scatter Plot - Site: York, SC

AIRS ID: 45-091-0006

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.02 0.04 0.06 0.08 0.1 0.12

Observed Ozone (PPM)

Modeled Ozone (PPM)

8-hour Ozone Scatter Plot - Site: York, SC

AIRS ID: 45-091-0006

0

0.02

0.04

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0.08

0.1

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Observed Ozone (PPM)

Modeled Ozone (PPM)

Figure 4.4-8 York, SC 1-hour (top) And 8-hour (bottom) Scatter Plots For May Through 

September 
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5 Time Series 

The time series plots of hourly model predicted ozone (green line) and hourly observed ozone 

(black stars) are presented in this section. There are time series plots for both 1-hour and 8-hour 

ozone concentrations for each of the months from May through September. Time series plots 

were created for the VISTAS/ASIP region of the 12km modeling domain, for North Carolina, for 

South Carolina, and individually for each of the ozone monitors in the Metrolina region. 

On each page, the 1-hour ozone time series plot is presented first (top) and the 8-hour ozone time 

series plots is present second (bottom) for the respective month and the respective region or 

monitoring site. 

5.1 12 km Domain Time Series Plots – VISTAS/ASIP States Only 

Overall the air quality model does an excellent job at capturing the diurnal pattern for both 1-

hour and 8-hour ozone (Figure 5.1-1 through Figure 5.1-5). The model tends to over predict the 

minimum ozone values over the course of the May through September time frame, but this is 

expected given the well known issue of air quality models generally not capturing the absolute 

overnight ozone minimums very well. This overnight over prediction of ozone is not expected to 

cause any issues with the application of the modeled attainment test as these lower ozone 

concentrations are not considered in this test. There is a slight under prediction of peak ozone 

values once you reach the core of the ozone season (June, July, and August). Despite this slight 

under prediction of the ozone peaks, several high ozone episodes and the subsequent clean out 

events are well captured by the modeling. This is a good indication that both the meteorological 

and air quality models are representing the large synoptic weather and air quality patterns well 

throughout the duration of this summer season. 
Model Performance Evaluation 68 

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 Figure 5.1-1 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For May 
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Figure 5.1-2 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For June 
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Figure 5.1-3 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For July 
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Figure 5.1-4 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For August 
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Figure 5.1-5 12km Domain – VISTAS/ASIP States Only 1-hour (top) And 8-hour (bottom) 

Time Series Plots For September 
Model Performance Evaluation 73 

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5.2 12 km Domain Time Series Plots – North Carolina 

From just the North Carolina perspective, the air quality model continues to do an excellent job 

at capturing the diurnal pattern for both 1-hour and 8-hour ozone (Figures 5.2-1 through 5.2-5). 

As with the VISTAS/ASIP region, the model under predicts the peak ozone values at times 

throughout the summer season as well as the overnight over prediction issue previously 

discussed. In particular, a portion of the month of May and the last few days of August and 

September show a more notable under prediction of the afternoon peak ozone concentrations. 

Overall, the air quality model continues to capture the various synoptic weather and air quality 

cycles quite well and is within acceptable tolerances for model performance. 
Model Performance Evaluation 74 

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Figure 5.2-1 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For May 
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Figure 5.2-2 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For June 
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Figure 5.2-3 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For July 
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Figure 5.2-4 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For August 
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Figure 5.2-5 12km Domain – North Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For September 
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5.3 12 km Domain Time Series Plots – South Carolina 

For South Carolina, the air quality model does an excellent job at capturing the diurnal pattern 

for both 1-hour and 8-hour ozone (Figures 5.3-1 through 5.3-5). The model under predicts the 

peak ozone values at times throughout the summer season as well as the overnight over 

prediction issue previously discussed. As with the North Carolina time series analysis, a portion 

of the month of May and the last few days of August and September show a more notable under 

prediction of the afternoon peak ozone concentrations. Overall, the air quality model continues 

to capture the various synoptic weather and air quality cycles quite well and is within acceptable 

tolerances for model performance. 
Model Performance Evaluation 80 

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Figure 5.3-1 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For May 
Model Performance Evaluation 81 

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Figure 5.3-2 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For June 
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Figure 5.3-3 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For July 
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Figure 5.3-4 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For August 
Model Performance Evaluation 84 

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Figure 5.3-5 12km Domain – South Carolina 1-hour (top) And 8-hour (bottom) Time 

Series Plots For September 
Model Performance Evaluation 85 

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5.4 Metrolina Monitor Specific Time Series Plots 

Finally, the time series for the individual ozone monitoring sites in the Metrolina region are 

present in Figures 5.4.1-1 through 5.4.8-5 on the following pages. There are 8 monitoring sites 

with 5 months presented for a total of 40 pages of 1-hour and 8-hour times series 

As with the larger domain time series plots and analyses presented earlier in this section, the air 

quality model tends to slightly under predict peak 1-hour and 8-hour ozone values. The over 

prediction of the nighttime minimum issue is more noticeable in the individual monitoring site 

time series, especially this more urbanized collection of sites due to the higher night time 

nitrogen oxide (NOx) environment found in such a metropolitan region. The NOx emissions 

titrate the ozone after sunset and the ozone levels decrease dramatically. The air quality model 

does not replicate this type of phenomenon very well. Again, the nighttime minimum over 

prediction is not an issue with respect to the modeled attainment test and is not of significant 

concern in this modeling exercise. The ability of the air quality model to very accurately capture 

the synoptic cycles from high ozone episodes to very clean periods is best demonstrated in these 

individual monitor time series. Based on all of the data presented in these time series plots, 

NCDAQ concludes that the air quality modeling continues to meet all requirements for further 

application in the modeled attainment test. 
Model Performance Evaluation 86 

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Monitor: Arrowood (37-119-1005) 

Month: May 

 Figure 5.4.1-1 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 87 

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Monitor: Arrowood (37-119-1005) 

Month: June

 Figure 5.4.1-2 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 88 

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Monitor: Arrowood (37-119-1005) 

Month: July 

 Figure 5.4.1-3 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 89 

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Monitor: Arrowood (37-119-1005) 

Month: August 

 Figure 5.4.1-4 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 90 

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Monitor: Arrowood (37-119-1005) 

Month: September 

 Figure 5.4.1-5 Arrowood 1-hour (top) And 8-hour (bottom) Time Series Plots For 

September 
Model Performance Evaluation 91 

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Monitor: County Line (37-119-1009) 

Month: May 

 Figure 5.4.2-1 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 92 

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Monitor: County Line (37-119-1009) 

Month: June 

 Figure 5.4.2-2 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 93 

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Monitor: County Line (37-119-1009) 

Month: July 

 Figure 5.4.2-3 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 94 

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Monitor: County Line (37-119-1009) 

Month: August 

 Figure 5.4.2-4 County Line 1-hour (top) And 8-hour (bottom) Time Series Plots For 

August 
Model Performance Evaluation 95 

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Monitor: County Line (37-119-1009) 

Month: September 

 Figure 5.4.2-5 County Line1-hour (top) And 8-hour (bottom) Time Series Plots For 

September 
Model Performance Evaluation 96 

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Monitor: Crouse (37-109-0004) 

Month: May 

 Figure 5.4.3-1 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 97 

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Monitor: Crouse (37-109-0004) 

Month: June 

 Figure 5.4.3-2 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 98 

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Monitor: Crouse (37-109-0004) 

Month: July 

 Figure 5.4.3-3 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 99 

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Monitor: Crouse (37-109-0004) 

Month: August 

 Figure 5.4.3-4 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
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Monitor: Crouse (37-109-0004) 

Month: September 

 Figure 5.4.3-5 Crouse 1-hour (top) And 8-hour (bottom) Time Series Plots For September 
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Monitor: Enochville (37-159-0022) 

Month: May 

 Figure 5.4.4-1 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 102 

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Monitor: Enochville (37-159-0022) 

Month: June 

 Figure 5.4.4-2 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 103 

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Monitor: Enochville (37-159-0022) 

Month: July 

 Figure 5.4.4-3 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 104 

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Monitor: Enochville (37-159-0022) 

Month: August 

 Figure 5.4.4-4 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 105 

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Monitor: Enochville (37-159-0022) 

Month: September 

 Figure 5.4.4-5 Enochville 1-hour (top) And 8-hour (bottom) Time Series Plots For 

September 
Model Performance Evaluation 106 

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Monitor: Garinger (37-119-0041) 

Month: May 

 Figure 5.4.5-1 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 107 

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Monitor: Garinger (37-119-0041) 

Month: June 

 Figure 5.4.5-2 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 108 

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Monitor: Garinger (37-119-0041) 

Month: July 

 Figure 5.4.5-3 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 109 

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Monitor: Garinger (37-119-0041) 

Month: August 

 Figure 5.4.5-4 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 110 

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Monitor: Garinger (37-119-0041) 

Month: September 

 Figure 5.4.5-5 Garinger 1-hour (top) And 8-hour (bottom) Time Series Plots For 

September 
Model Performance Evaluation 111 

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Monitor: Monroe (37-179-0003) 

Month: May 

 Figure 5.4.6-1 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 112 

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Monitor: Monroe (37-179-0003) 

Month: June 

 Figure 5.4.6-2 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 113 

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Monitor: Monroe (37-179-0003) 

Month: July 

 Figure 5.4.6-3 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 114 

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Monitor: Monroe (37-179-0003) 

Month: August 

 Figure 5.4.6-4 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 115 

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Monitor: Monroe (37-179-0003) 

Month: September 

 Figure 5.4.6-5 Monroe 1-hour (top) And 8-hour (bottom) Time Series Plots For September 
Model Performance Evaluation 116 

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Monitor: Rockwell (37-159-0021) 

Month: May 

 Figure 5.4.7-1 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 117 

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Monitor: Rockwell (37-159-0021) 

Month: June 

 Figure 5.4.7-2 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 118 

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Monitor: Rockwell (37-159-0021) 

Month: July 

 Figure 5.4.7-3 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 119 

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Monitor: Rockwell (37-159-0021) 

Month: August 

 Figure 5.4.7-4 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 120 

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Monitor: Rockwell (37-159-0021) 

Month: September 

 Figure 5.4.7-5 Rockwell 1-hour (top) And 8-hour (bottom) Time Series Plots For 

September 
Model Performance Evaluation 121 

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Monitor: York, SC (45-091-0006) 

Month: May 

 Figure 5.4.8-1 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For May 
Model Performance Evaluation 122 

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Monitor: York, SC (45-091-0006) 

Month: June 

 Figure 5.4.8-2 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For June 
Model Performance Evaluation 123 

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Monitor: York, SC (45-091-0006) 

Month: July 

 Figure 5.4.8-3 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For July 
Model Performance Evaluation 124 

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Monitor: York, SC (45-091-0006) 

Month: August 

 Figure 5.4.8-4 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For August 
Model Performance Evaluation 125 

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Monitor: York, SC (45-091-0006) 

Month: September 

Figure 5.4.8-5 York, SC 1-hour (top) And 8-hour (bottom) Time Series Plots For 

September