[Federal Register: June 7, 2010 (Volume 75, Number 108)]
[Proposed Rules]
[Page 32142-32143]
[DOCID:fr07jn10-12]

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DEPARTMENT OF LABOR

Occupational Safety and Health Administration

29 CFR Part 1910

RIN 1218-AC41

Combustible Dust

AGENCY: Occupational Safety and Health Administration (OSHA), Labor.

ACTION: Notice of combustible dust Web Chat.

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SUMMARY: OSHA invites interested parties to participate in a Web Chat
on the workplace hazards of combustible dust. OSHA plans to use the
information gathered in response to this Web Chat in developing a
proposed standard for combustible dust.

DATES: The Web Chat will be held on June 28, 2010, at 1 p.m. EDT.

ADDRESSES:

Registration

    Participants are requested to provide their name, affiliation, and
e-mail address so OSHA can respond to comments or seek clarification.

Web Site

    Participants can access the Web Chat at http://www.dol.gov/dol/
chat.htm. The Web Blog will remain accessible for additional feedback
through July 7, 2010.

FOR FURTHER INFORMATION CONTACT: Information regarding this notice is
available from the following sources:
     Press inquiries. Contact Jennifer Ashley, Director, OSHA
Office of Communications, Room N-3647, U.S. Department of Labor, 200
Constitution Avenue, NW., Washington, DC 20210; telephone: (202) 693-
1999.
     General and technical information regarding Combustible
Dust. Contact Mat Chibbaro, P.E., Fire Protection Engineer, Office of
Safety Systems, OSHA Directorate of Standards and Guidance, Room N-
3609, U.S. Department of Labor, 200 Constitution Avenue, NW.,
Washington, DC 20210; telephone:<PHONE_NUMBER>.
     Technical information regarding Web Chat logistics and
electronic access. Contact Andy Bailey, DOL Web Content Manager, Office
of Public Affairs, Division of Enterprise Communications, U.S.
Department of Labor, 200 Constitution Avenue, NW., Washington, DC
20210; telephone:<PHONE_NUMBER>.
     Copies of this Federal Register notice. Electronic copies
are available at http://www.regulations.gov. This

Federal Register notice, as well as news releases and other relevant
information, also are available on the OSHA Web page at http://
www.osha.gov.

SUPPLEMENTARY INFORMATION:

I. Background

    The hazards of combustible dust encompass a wide array of
materials, industries, and processes. Any combustible material can burn
rapidly when in a finely divided form. Materials that may form
combustible dust include, but are not limited to, wood, coal, plastics,
biosolids, candy, sugar, spice, starch, flour, feed, grain, fertilizer,
tobacco, paper, soap, rubber, drugs, dried blood, dyes, certain
textiles, and metals (such as aluminum and magnesium). Industries that
may have combustible dust hazards include, among others: animal food
manufacturing, grain handling, food manufacturing, wood product
manufacturing, chemical manufacturing, textile manufacturing, furniture
manufacturing, metal processing, fabricated metal products and
machinery manufacturing, pesticide manufacturing, pharmaceutical
manufacturing, tire manufacturing, production of rubber and plastics,
plastics and rubber products manufacturing, recycling, wastewater
treatment, and coal handling.
    OSHA is developing a standard that will comprehensively address the
fire and explosion hazards of combustible dust. The Agency issued an
Advanced Notice of Proposed Rulemaking (ANPR) that requested comments,
including data and other information, on issues related to the hazards
of combustible dust in the workplace. (74 FR 54334, Oct. 21, 2009).
OSHA plans to use the information received in response to the ANPR, at
the stakeholder meetings, and during the Web Chat in developing a
proposed standard for combustible dust.

II. Web Chat and Stakeholder Meetings

    OSHA conducted stakeholder meetings in Washington, DC, on December
14, 2009; in Atlanta, GA, on February 17, 2010; and in Chicago, IL, on
April 21, 2010. This notice announces a Web Chat to gather additional
information beyond that provided in the stakeholder meetings. OSHA will
pose questions and interact with participants for one hour, beginning
at 1 p.m. EDT on June 28, 2010. In addition to the live Web Chat, OSHA
will also post additional information on the Department of Labor Blog,
http://www.dol.gov/dol/chat.htm. and invites the public to provide
feedback via comments on these entries. The Web Blog will remain
accessible through July 7, 2010. OSHA will monitor the site, provide
additional information, and pose additional questions when appropriate.
    OSHA will introduce areas to which participants should focus their
views, concerns, and issues related to the hazards of combustible dust.
The Web Chat will center on major issues such as:
     Scope.
     Balance between performance and specification based
requirements.
     Economic impacts.
     Definitions.

III. Public Participation

    To register, follow the instructions provided on the Web site.
Participants are asked to provide the following information so that
OSHA can solicit clarification of comments, if necessary:
     Name.
     E-mail address.
     Organization being represented.
     Stakeholder category: government, industry, standards-
developing organization, research or testing agency, union, trade
association, insurance, fire protection equipment manufacturer,
consultant, or other (if other, please specify).
     Industry sector (if applicable): metals, wood products,
grain or wet corn milling, food (including sugar), pharmaceutical or
chemical manufacturing, paper products, rubber or plastics, coal, or
other (if other, please specify).

Authority and Signature

    This document was prepared under the direction of David Michaels,
PhD, MPH, Assistant Secretary of Labor for Occupational Safety and
Health, U.S. Department of Labor, pursuant to sections 4, 6, and 8 of
the Occupational Safety and Health Act of 1970 (29 U.S.C. 653, 655,
657), 29 CFR part 1911, and Secretary's Order 5-2007 (72 FR 31160).

    Signed at Washington, DC, on June 1, 2010.
David Michaels,
Assistant Secretary of Labor for Occupational Safety and Health.
[FR Doc. 2010-13467 Filed 6-4-10; 8:45 am]
BILLING CODE 4510-26-P


[Federal Register Volume 88, Number 54 (Tuesday, March 21, 2023)]
[Notices]
[Pages 16966-16967]
[FR Doc No: 2023-05780]

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DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Docket No. RM98-1-000]

Records Governing Off-the-Record Communications; Public Notice

    This constitutes notice, in accordance with 18 CFR 385.2201(b), of
the receipt of prohibited and exempt off-the-record communications.
    Order No. 607 (64 FR 51222, September 22, 1999) requires Commission
decisional employees, who make or receive a prohibited or exempt off-
the-record communication relevant to the merits of a contested
proceeding, to deliver to the Secretary of the Commission, a copy of
the communication, if written, or a summary of the substance of any
oral communication.
    Prohibited communications are included in a public, non-decisional
file associated with, but not a part of, the decisional record of the
proceeding. Unless the Commission determines that the prohibited
communication and any responses thereto should become a part of the
decisional record, the prohibited off-the-record communication will not
be considered by the Commission in reaching its decision. Parties to a
proceeding may seek the opportunity to respond to any facts or
contentions made in a prohibited off-the-record communication and may
request that the Commission place the prohibited communication and
responses thereto in the decisional record. The Commission will grant
such a request only when it determines that fairness so requires. Any
person identified below as having made a prohibited off-the-record
communication shall serve the document on all parties listed on the
official service list for the applicable proceeding in accordance with
Rule 2010, 18 CFR 385.2010.
    Exempt off-the-record communications are included in the decisional
record of the proceeding, unless the communication was with a
cooperating agency as described by 40 CFR 1501.6, made under 18 CFR
385.2201(e)(1)(v).
    The following is a list of off-the-record communications recently
received by the Secretary of the Commission. This filing may be viewed
on the Commission's website at http://www.ferc.gov using the eLibrary
link. Enter the docket number, excluding the last three digits, in the
docket number field to access the document. For assistance, please
contact FERC Online Support at [email protected] or toll free
at<PHONE_NUMBER>, or for TTY, contact<PHONE_NUMBER>.

------------------------------------------------------------------------
                                                        Presenter or
            Docket Nos.                File date          requester
------------------------------------------------------------------------
Prohibited:
    1. CP20-55-000................        3-1-2023  FERC Staff.\1\
    2. CP20-55-000................        3-1-2023  FERC Staff.\2\
    3. CP20-55-000................        3-1-2023  FERC Staff.\3\
    4. CP20-55-000................        3-1-2023  FERC Staff.\4\
    5. CP20-55-000................        3-3-2023  FERC Staff.\5\
    6. CP20-55-000................        3-7-2023  FERC Staff.\6\
    7. CP20-55-000................        3-7-2023  FERC Staff.\7\
    8. CP20-55-000................        3-7-2023  FERC Staff.\8\
    9. CP20-55-000................        3-7-2023  FERC Staff.\9\
    10. CP20-55-000...............        3-7-2023  FERC Staff.\10\
    11. CP20-55-000...............        3-7-2023  FERC Staff.\11\
    12. CP20-55-000...............        3-7-2023  FERC Staff.\12\
    13. CP20-55-000...............        3-7-2023  FERC Staff.\13\
    14. CP20-55-000...............        3-7-2023  FERC Staff.\14\
    15. CP20-55-000...............        3-7-2023  FERC Staff.\15\
    16. CP20-55-000...............        3-7-2023  FERC Staff.\16\
    17. CP20-55-000...............       3-13-2023  FERC Staff.\17\
    18. CP20-55-000...............       3-13-2023  FERC Staff.\18\
    19. CP20-55-000...............       3-13-2023  FERC Staff.\19\
    20. CP20-55-000...............       3-13-2023  FERC Staff.\20\
    21. CP20-55-000...............       3-13-2023  FERC Staff.\21\
    22. CP20-55-000...............       3-13-2023  FERC Staff.\22\
    23. CP20-55-000...............       3-13-2023  FERC Staff.\23\
    24. CP20-55-000...............       3-13-2023  FERC Staff.\24\
    25. CP20-55-000...............       3-13-2023  FERC Staff.\25\
    26. CP20-55-000...............       3-13-2023  FERC Staff.\26\

    27. CP20-55-000...............       3-13-2023  FERC Staff.\27\
    28. CP20-55-000...............       3-13-2023  FERC Staff.\28\
    29. CP20-55-000...............       3-13-2023  FERC Staff.\29\
    30. CP20-55-000...............       3-13-2023  FERC Staff.\30\
    31. CP20-55-000...............       3-13-2023  FERC Staff.\31\
    32. CP20-55-000...............       3-13-2023  FERC Staff.\32\
    33. CP20-55-000...............       3-13-2023  FERC Staff.\33\
    34. CP16-454-000..............       3-15-2023  FERC Staff.\34\
Exempt:
    1. CP22-21-000, CP22-22-000...        3-6-2023  Louisiana House of
                                                     Representative Clay
                                                     Higgins.
    2. CP17-40-000................        3-7-2023  U.S. Senator Tammy
                                                     Duckworth.
    3. CP22-2-000.................       3-13-2023  Washington State
                                                     Governor Jay
                                                     Inslee.
    4. CP16-454-000...............       3-15-2023  Cameron County Texas
                                                     Judge Eddie
                                                     Trevino, Jr.
------------------------------------------------------------------------
\1\ Email comments dated 2/27/23 from Jennifer Ho.
\2\ Email comments dated 2/27/23 from Thomas Coleman.
\3\ Email comments dated 2/28/23 from Rachel Kosarin.
\4\ Email comments dated 2/28/23 from Keith Olcott.
\5\ Email comments dated 3/2/23 from Robby Roberts.
\6\ Email comments dated 3/3/23 from Dara Olmsted Silverstein.
\7\ Email comments dated 3/3/23 from Lynn Weller.
\8\ Email comments dated 3/3/23 from Nikki Alvarado.
\9\ Email comments dated 3/4/23 from Jennifer Aminzade.
\10\ Email comments dated 3/4/23 from Staci Edwards.
\11\ Email comments dated 3/4/23 from Liz Peltekian.
\12\ Email comments dated 3/5/23 from Dora Nomamiukor.
\13\ Email comments dated 3/5/23 from Jamie Usrey.
\14\ Email comments dated 3/6/23 from Elaine Salinger.
\15\ Email comments dated 3/6/23 from Lucinda Young.
\16\ Email comments dated 3/7/23 from Mary Ruth Gross.
\17\ Email comments dated 3/8/23 from Ari Thomas.
\18\ Email comments dated 3/10/23 from William Niemand.
\19\ Email comments dated 3/12/23 from Cassie Bowler Dupras.
\20\ Email comments dated 3/7/23 from Daylan Forguson.
\21\ Email comments dated 3/13/23 from Diane Gleave.
\22\ Email comments dated 3/8/23 from Ginger Vollmar.
\23\ Email comments dated 3/9/23 from Jacquie Hilterman.
\24\ Email comments dated 3/7/23 from Julia Hudson.
\25\ Email comments dated 3/13/23 from Karen Daiter.
\26\ Email comments dated 3/8/23 from Kathleen Watson.
\27\ Email comments dated 3/13/23 from Kent Kasper.
\28\ Email comments dated 3/8/23 from Leslie Alden.
\29\ Email comments dated 3/9/23 from Mary Ann Osborne.
\30\ Email comments dated 3/9/23 from Robin Weller.
\31\ Email comments dated 3/13/23 from Susan Baum.
\32\ Email comments dated 3/13/23 from Suzie Ross.
\33\ Email comments dated 3/7/23 from Todd Weber.
\34\ Email comments dated 3/13/23 from Eduardo A Campirano.

    Dated: March 15, 2023.
Debbie-Anne A. Reese,
Deputy Secretary.
[FR Doc. 2023-05780 Filed 3-20-23; 8:45 am]
BILLING CODE 6717-01-P


Technical Support Document:

2002 CMAQ Model Performance Evaluation

 for Ozone and Particulate Matter

U.S. Environmental Protection Agency

Office of Air Quality Planning and Standards

Air Quality Assessment Division

Research Triangle Park, NC 27711

March 2008

Introduction

An operational model performance evaluation for ozone and PM2.5 and its related speciated components was conducted using 2002 State/local monitoring sites data in order to estimate the ability of the CMAQ modeling system to replicate the base year concentrations for the 12-km Eastern and Western United States domain .  This evaluation principally comprises statistical assessments of model versus observed pairs that were paired in space and time on a daily or weekly basis, depending on the sampling frequency of each network (measured data).  For certain time periods with missing ozone and PM2.5 observations we excluded the CMAQ predictions from those time periods in our calculations.  It should be noted when pairing model and observed data that each CMAQ concentration represents a grid-cell volume-averaged value, while the ambient network measurements are made at specific locations.  In conjunction with the model performance statistics, we also provide spatial plots for individual monitors of the calculated bias and error statistics (defined below).  Statistics were generated for the 12-km Eastern US domain (EUS), 12-km Western US domain (WUS), and five large subregions: Midwest, Northeast, Southeast, Central, and West U.S.  The Atmospheric Model Evaluation Tool (AMET) was used to conduct the evaluation described in this document.

The ozone evaluation primarily focuses on observed and predicted hourly ozone concentrations and eight-hour daily maximum ozone concentrations at a threshold of 40ppb.  This ozone model performance was limited to the ozone season modeled for the Ozone National Ambient Air Quality Standard (NAAQS) Final Rule: May, June, July, August, and September.  Ozone ambient measurements for 2002 were obtained from the Air Quality System (AQS) Aerometric Information Retrieval System (AIRS).  A total of 1178 ozone measurement sites were included for evaluation.  The ozone data were measured and reported on an hourly basis.

The PM2.5 evaluation focuses on PM2.5 total mass and its components including sulfate (SO4), nitrate (NO3), total nitrate (TNO3=NO3+HNO3), ammonium (NH4), elemental carbon (EC), and organic carbon (OC).  The PM2.5 performance statistics were calculated for each month and season individually and for the entire year, as a whole.  Seasons were defined as:  winter (December-January-February), spring (March-April-May), summer (June-July-August), and fall (September-October-November).  PM2.5 ambient measurements for 2002 were obtained from the following networks for model evaluation:  Speciation Trends Network (STN- total of 199 sites), Interagency Monitoring of PROtected Visual Environments (IMPROVE- total of 150 sites), and Clean Air Status and Trends Network (CASTNet- total of 83 sites).  The pollutant species included in the evaluation for each network are listed in Table 1-1.  For PM2.5 species that are measured by more than one network, we calculated separate sets of statistics for each network.

Table 1-1. PM2.5 monitoring networks and pollutants species included in the CMAQ performance evaluation.

Ambient Monitoring Networks 	Particulate Species

	PM2.5 Mass	SO4	NO3	TNO3	NH4	EC	OC

IMPROVE 	X 	X 	X 	 	X 	X 	X

CASTNet 	 	X 	 	X 	X

STN 	X 	X 	X 	 	X 	X 	X

Note that TNO3 = (NO3 + HNO3)

There are various statistical metrics available and used by the science community for model performance evaluation.  For a robust evaluation, the principal evaluation statistics used to evaluate CMAQ performance were two bias metrics, normalized mean bias and fractional bias; and two error metrics, normalized mean error and fractional error.

Normalized mean bias  SEQ CHAPTER \h \r 1  (NMB) is used as a normalization to facilitate a range of concentration magnitudes.  This statistic averages the difference (model - observed) over the sum of observed values.  NMB is a useful model performance indicator because it avoids over inflating the observed range of values, especially at low concentrations.  Normalized mean bias is defined as:

 *100

Normalized mean error (NME) is also similar to NMB, where   SEQ CHAPTER \h \r 1 the performance statistic is used as a normalization of the mean error.   NME calculates the absolute value of the difference (model - observed) over the sum of observed values.  Normalized mean error is defined as:

 *100

Fractional bias is defined as:

 *100, where P = predicted concentrations and O = observed

concentrations.  FB is a useful model performance indicator because it has the advantage of equally weighting positive and negative bias estimates.  The single largest disadvantage in this estimate of model performance is that the estimated concentration (i.e., prediction, P) is found in both the numerator and denominator.  Fractional error (FE) is similar to fractional bias except the absolute value of the difference is used so that the error is always positive.  Fractional error is defined as:

 *100

The “acceptability” of model performance was judged by comparing our CMAQ 2002 performance results to the range of performance found in recent regional ozone and PM2.5 model applications (e.g., Clean Air Interstate Rule, Final PM NAAQS Rule).  These other modeling studies represent a wide range of modeling analyses which cover various models, model configurations, domains, years and/or episodes, chemical mechanisms, and aerosol modules.  Overall, the NMB, NME, FB, and FE statistics shown in Tables A-2 thru A-10 below for CMAQ predicted 2002 ozone and PM2.5 concentrations are within the range or close to that found in recent OAQPS applications.  The CMAQ model performance results give us confidence that our applications of CMAQ using this 2002 modeling platform provide a scientifically credible approach for assessing ozone and PM2.5 concentrations for the purposes of the Ozone NAAQS Final Rule.  We discuss in the following sections the bias and error results for the hourly ozone concentrations and eight-hour daily maximum ozone concentrations evaluated at a threshold of 40 ppb as well as the annual and seasonal PM2.5 and its related speciated components.

Ozone Performance Evaluation

Hourly Ozone Performance: Threshold of 40 ppb

Table 2-1 provides hourly ozone model performance statistics calculated for a threshold of 40 ppb of observed and modeled concentrations, restricted to the ozone season modeled for the 12-km Eastern and Western U.S. domain and the five subregions (Midwest, Northeast, Southeast, Central and Western U.S.).  Spatial plots of the NMB and NME statistics (units of percent) for individual monitors are also provided as a complement to the tabular statistical data (Figures 2-1 – 2-24).  Hourly ozone model performance is under-predicted in both the 12-km EUS and WUS when applying a threshold of 40 ppb for the modeled ozone season (May-September).  For the 12-km Eastern domain, the bias and error statistics are comparable for the aggregate of the ozone season and for each individual ozone month modeled, with a NMB range of -1% to -10% and a FB range of -2% to -12%, and a NME range of 16% to 18% and a FE range of 17% to 19%.  Likewise, for the 12-km Western domain, the bias and error statistics are similar between the ozone seasonal aggregate and the individual months, with a NMB range of -4% to -12% and a FB range of -5% to -15%, and a NME range of 16% to 21% and a FE range of 17% to 24%.  Hourly ozone model performance when compared across the five subregions shows slightly better performance in the Southeast, with NMB and FB values ranging from -2% to -10% and NME and FE values of approximately 14% to 17%.  In general, the Northeast, Midwest, Central and West U.S. exhibit similar bias and error statistics for the episodes modeled, NMB= -1% to -10%; FB= -1% to -17%; NME=16% to 21%; and FE= 17% to 25%.  The month of May shows a slightly better bias and error model performance results, although the results are spatially and temporally comparable across the months modeled.

Table 2-1.  CMAQ 2002 hourly ozone model performance statistics calculated for a threshold of 40 pbb.

CMAQ 2002 Hourly Ozone:

Threshold of 40 ppb	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

May	12-km EUS	241185	-0.7	15.9	-2.0	17.1

	12-km WUS	124931	-3.7	15.9	-5.0	17.3

	Northeast 	51055	1.2	17.1	-0.3	18.2

	Midwest 	55859	3.3	16.2	2.4	16.9

	Southeast	69073	-2.5	14.1	-3.1	14.8

	Central 	41728	-6.4	17.3	-9.2	20.3

	West	111385	-3.9	16.1	-5.2	17.6

June	12-km EUS	256263	-7.5	16.8	-9.0	18.6

	12-km WUS	125662	-8.37	17.7	-9.3	19.1

	Northeast	61354	-8.46	17.3	-9.9	19.1

	Midwest	54515	-7.19	17.9	-8.3	19.6

	Southeast	67867	-7.2	15.3	-7.6	16.3

	Central 	46026	-10.0	17.5	-13.5	21.2

	West	109157	-8.8	18.2	-9.9	19.7

July	12-km EUS	257076	-5.3	17.7	-6.6	19.2

	12-km WUS	116785	-12.0	21.5	-14.9	24.3

	Northeast	66774	-3.9	17.0	-4.8	18.0

	Midwest	59360	-10.5	19.4	-12.3	21.7

	Southeast	68619	-3.6	16.5	-3.9	17.2

	Central	36021	-3.6	18.7	-6.3	21.1

	West	104321	-13.6	21.8	-16.8	24.9

August	12-km EUS	235090	-8.7	17.8	-10.2	19.7

	12-km WUS	125575	-7.91	20.1	-10.2	22.1

	Northeast	53837	-6.4	16.7	-7.4	18.0

	Midwest	54179	-10.8	19.1	-12.4	21.4

	Southeast	62506	-9.4	17.3	-9.9	18.5

	Central	41456	-9.3	18.7	-12.8	22.4

	West	110225	-8.5	20.6	-11.1	22.8

September	12-km EUS	179156	-9.9	17.2	-11.8	19.5

	12-km WUS	99710	-10.7	19.0	-12.7	21.1

	Northeast	44678	-8.7	16.3	-10.6	18.4

	Midwest	34285	-11.4	18.5	-12.9	20.4

	Southeast	41627	-8.2	16.5	-9.0	17.8

	Central 	41549	-12.8	18.8	-16.6	22.8

	West	83921	-11.7	20.0	-13.8	22.1

Seasonal Aggregate	12-km EUS	1168770	-6.4	17.1	-7.7	18.8

	12-km WUS 	592663	-8.4	18.8	-10.3	20.7

	Northeast	277698	-5.4	16.9	-6.5	18.4

	Midwest	258198	-7.3	18.3	-8.4	20.0

	Southeast	309692	-6.0	15.9	-6.4	16.8

	Central U	206780	-8.6	18.2	-11.9	21.6

	West	519009	-9.2	19.3	-11.2	21.3

Figure 2-1.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, May 2002.

Figure 2-2.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, May 2002.

Figure 2-3.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, June 2002.

Figure 2-4.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, June 2002.

Figure 2-5.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, July 2002.

Figure 2-6.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, July 2002.

Figure 2-7.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, August 2002.

Figure 2-8.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, August 2002.

Figure 2-9.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, September 2002.

Figure 2-10.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, September 2002.

Figure 2-11.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, seasonal aggregate 2002.

Figure 2-12.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, seasonal aggregate 2002.

Figure 2-13.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, May 2002.

Figure 2-14.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, May 2002.

Figure 2-15.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, June 2002.

Figure 2-16.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, June 2002.

Figure 2-17.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, July 2002.

Figure 2-18.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, July 2002.

Figure 2-19.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, August 2002.

Figure 2-20.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, August 2002.

Figure 2-21.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, September 2002.

Figure 2-22.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, September 2002.

Figure 2-23.  Normalized Mean Bias (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, seasonal aggregate 2002.

Figure 2-24.  Normalized Mean Error (%) of hourly ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, seasonal aggregate 2002.

Eight-hour Ozone Performance: Threshold of 40 ppb

Table 2-2 presents eight-hour daily maximum ozone model performance bias and error statistics for the entire range of observed and modeled concentrations at a threshold of 40 ppb for the ozone season modeled for the 12-km Eastern and Western U.S. domain and the corresponding subregions defined above.  Spatial plots of the NMB and NME statistics (units of percent) for individual monitors based on the aggregate and the individual ozone months modeled respectively are shown in Figures 2-25 through  2-48.  In general, CMAQ slightly under-predicts eight-hourly daily maximum ozone with a threshold of 40 ppb, which also exhibits better model performance than the ozone hourly analysis for these modeled time periods.  For the 12-km Eastern domain, the bias statistics are within the range of approximately -1% to -6%, while the error statistics range from 12% to 13% for the aggregate of the ozone season and for most of the months modeled.  There was a slight over-prediction of eight-hour daily maximum ozone in the month of May (bias of approximately 4%).  For the 12-km Western domain, the bias statistics are within the range of approximately 0% to -%, while the error statistics range from 12% to 13% for the aggregate of the ozone season and for the individual months modeled.  The Southeast region shows good model performance with bias and error statistics approximately -1% and 13%, respectively.  The five subregions show relatively similar eight-hour daily maximum ozone performance, with bias values ranging from 0% to -8% and error values ranging from 11% to 17%.

Table 2-2.  CMAQ 2002 eight-hour daily maximum ozone model performance statistics calculated for a threshold of 40 pbb.

CMAQ 2002 Eight-Hour Maximum Ozone:

Threshold of 40 ppb	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

May	12-km EUS	19172	3.9	12.7	4.3	12.6

	12-km WUS	9223	0.2	12.6	0.6	12.8

	Northeast	4255	6.7	14.3	6.8	14.2

	Midwest	4198	7.8	13.7	8.2	13.5

	Southeast	5470	0.6	10.9	1.1	11.0

	Central 	3379	0.3	12.3	0.7	12.4

	West	8155	-0.1	12.8	0.3	12.9

June	12-km EUS	19462	-3.9	12.3	-3.3	12.4

	12-km WUS	9029	-4.9	14.1	-4.2	14.2

	Northeast	4608	-5.3	12.5	-4.7	12.7

	Midwest	4104	-3.2	12.7	-2.2	12.8

	Southeast	5110	-4.8	11.8	-4.1	11.9

	Central 	3603	-4.5	12.2	-4.4	12.7

	West	7818	-5.3	14.5	-4.7	14.7

July	12-km EUS	20565	-1.6	13.5	-1.0	13.6

	12-km WUS	8809	-7.4	17.1	-8.1	18.0

	Northeast	5380	-0.7	13.0	-0.2	12.9

	Midwest	4368	-6.5	14.2	-5.8	14.4

	Southeast	5633	-0.9	13.0	-0.1	13.0

	Central 	3114	1.3	14.4	1.2	14.7

	West	7784	-9.0	17.2	-9.9	18.2

August	12-km EUS	19260	-5.1	13.2	-4.4	13.4

	12-km WUS	9551	-2.8	15.8	-3.1	16.1

	Northeast	4667	-2.9	12.4	-2.2	12.4

	Midwest	4012	-8.1	13.9	-7.5	14.2

	Southeast	5067	-6.4	13.4	-5.4	13.4

	Central 	3543	-4.0	13.5	-3.9	14.1

	West	8311	-3.2	16.1	-3.6	16.5

September	12-km EUS	15865	-6.2	12.6	-5.9	12.9

	12-km WUS	8185	-6.7	15.0	-6.9	15.5

	Northeast	4074	-6.0	11.8	-6.0	12.3

	Midwest	3120	-7.2	13.3	-6.5	13.3

	Southeast	3671	-4.5	12.6	-3.8	12.7

	Central	3492	-8.5	13.8	-8.7	14.5

	West	6911	-7.3	15.9	-7.6	16.4

Seasonal Aggregate	12-km EUS	94324	-2.6	12.9	-1.9	13.0

	12-km WUS	44797	-4.3	14.9	-4.2	15.3

	Northeast	22984	-1.9	12.8	-1.2	12.9

	Midwest	19802	-3.6	13.6	-2.5	13.7

	Southeast	24951	-3.1	12.4	-2.3	12.4

	Central 	17131	-3.3	13.2	-3.1	13.7

	West	38979	-4.9	15.3	-5.0	15.7

Figure 2-25.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, May 2002.

Figure 2-26.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, May 2002.

Figure 2-27.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, June 2002.

Figure 2-28.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, June 2002.

Figure 2-29.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, July 2002.

Figure 2-30.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, July 2002.

Figure 2-31.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, August 2002.

Figure 2-32.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, August 2002.

Figure 2-33.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, September 2002.

Figure 2-34.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, September 2002.

Figure 2-35.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, seasonal aggregate 2002.

Figure 2-36.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Eastern U.S. domain, seasonal aggregate 2002.

Figure 2-37.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, May 2002.

Figure 2-38.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, May 2002.

Figure 2-39.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, June 2002.

Figure 2-40.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, June 2002.

Figure 2-41.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, July 2002.

Figure 2-42.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for Western U.S., July 2002.

Figure 2-43.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, August 2002.

Figure 2-44.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, August 2002.

Figure 2-45.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, September 2002.

Figure 2-46.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, September 2002.

Figure 2-47.  Normalized Mean Bias (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for 12-km Western U.S. domain, seasonal aggregate 2002.

Figure 2-48.  Normalized Mean Error (%) of eight-hour daily maximum ozone (40 ppb threshold) by monitor for Western U.S., seasonal aggregate 2002.

PM2.5 Species Performance Evaluation

Annual PM2.5 Species Performance

Table 3-1 provides annual model performance statistics for PM2.5 and its component species for the 12-km Eastern domain, 12-km Western domain, and five subregions defined above (Midwest, Northeast, Southeast, Central, and West U.S.).  Spatial plots of the NMB and NME statistics (units of percent) for individual monitors are also provided in Figures 3-1 – 3-28.  In the East, annual total PM2.5 mass is over-predicted when compared at STN sites (bias of ~11% and error of ~43%) and under-predicted when compared at IMPROVE site (bias of ~ -2% and error of ~ 50%).  In the West, annual total PM2.5 mass is under-predicted when evaluated at STN sites and IMPROVE sites, with better performance at STN network (bias ~ -6).  Although not shown here, the mean observed concentrations of PM2.5 are approximately twice as high at the STN sites (EUS = ~13µg m-3; WUS = ~12µg m-3) as the IMPROVE sites (EUS = ~6µg m-3; WUS = ~4µg m-3), thus illustrating the statistical differences between the urban STN and rural IMPROVE networks.  Sulfate is consistently under-predicted at STN, IMPROVE, and CASTNet sites, with NMB values ranging from -26% to -3%.  Overall, sulfate performance is best in the East at urban STN sites (NMB =   -4% and NME = 33%).  Nitrate is over-predicted in the 12-km Eastern domain (NMB in the range of 18% to 48%), while nitrate is under-predicted in the 12-km Western domain (NMB in the range of -34% to -45%).  Likewise, model performance of total nitrate at CASTNet sites shows an over-prediction in the East (NMB = 24%) and an under-prediction in the West (NMB = -20%).  Ammonium model performance varies across the STN and CASTNet in the East and West, with an over-prediction in the Eastern domain and an under-prediction in the West.  Elemental carbon is over-predicted at STN sites in the East and West with a NMB of ~44%, FB of ~20%, NME of ~80%, and FE of ~60%.  Although, EC is under-predicted at IMPROVE sites in the East and West with a NMB of ~ -15%, FB of ~ -25%, NME of ~55%, and FE of ~55%.  Organic carbon is moderately under-predicted for all domains in the STN and IMPROVE networks (bias ~ -35% and error ~ 60%.  Differences in model predictions between IMPROVE and STN networks could be attributed to both the rural versus urban characteristics as well as differences in the measurement methodology between the two networks (e.g. blank correction factors, and filter technology used).

Table 3-1.  2002 CMAQ annual PM2.5 species model performance statistics.

CMAQ 2002 Annual	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	PM2.5                                       Total Mass	STN	12-km EUS 10307	10.8	42.8	5.4	42.6

12-km WUS	3000	-5.8	46.9	-3.1	45.0

Northeast	1516	14.9	35.6	13.2	34.4

Midwest	2780	20.5	48.2	16.6	42.6

Southeast	2554	-3.9	36.0	-10.0	39.7

Central 	2738	14.5	49.1	6.0	49.4

West	2487	-7.4	46.8	-4.5	44.8

	IMPROVE	12-km EUS	8436	-2.3	49.0	-5.7	51.4

12-km WUS	10123	-26.4	53.5	-26.3	57.5

Northeast	592	8.6	41.5	2.4	41.0

Midwest	2060	21.0	59.4	17.4	51.6

Southeast	1803	-13.1	41.2	-19.8	49.9

Central 	1624	-13.1	49.4	-17.6	57.0

West	9543	-27.8	53.1	-27.1	57.2

Sulfate	STN	12-km EUS	10157	-3.9	33.6	-9.7	38.4

12-km WUS	2926	-20.6	41.9	-12.2	43.5

Northeast	1487	3.6	34.9	-2.9	36.2

Midwest	2730	-4.3	29.1	-8.8	33.6

Southeast	2541	-7.6	33.4	-16.3	38.8

Central	2686	-3.2	39.2	-7.2	44.3

West	2446	-26.1	44.9	-15.8	44.8

	IMPROVE	12-km EUS	8532	-10.8	33.0	-7.2	40.6

12-km WUS	10232	-7.5	42.4	7.6	45.7

Northeast	597	-4.9	29.9	-10.0	35.7

Midwest	2070	-12.3	30.1	-9.9	36.1

Southeast	1805	-9.5	32.9	-16.8	40.5

Central 	1671	-16.1	35.0	-16.0	42.4

West	9645	-5.5	43.5	8.6	45.9

	CASTNet	12-km EUS	3173	-11.3	20.5	-16.3	26.1

12-km WUS	1158	-21.3	34.6	-11.2	35.9

Northeast	663	-8.3	19.3	-16.3	24.3

Midwest	839	-12.3	17.9	-15.6	21.6

Southeast	1085	-11.2	21.5	-17.8	27.2

Central 	229	-20.7	27.3	-27.4	33.6

West	1118	-20.4	35.3	-10.7	36.1

Nitrate	STN	12-km EUS	8770	18.3	65.9	-29.1	84.5

12-km WUS	2726	-45.0	63.1	-70.6	95.0

Northeast	1488	17.4	59.1	-5.0	67.3

Midwest	2731	32.7	70.4	-10.9	78.1

Southeast	2540	8.6	84.6	-64.7	107.5

Central 	1298	12.7	52.5	-13.4	69.1

West	2446	-47.5	62.8	-73.8	95.4

	IMPROVE	12-km EUS	8514	48.4	106.8	-52.8	116.4

12-km WUS	10110	-34.8	80.67	-101.0	130.0

Northeast	597	43.0	86.0	-37.0	102.8

Midwest	2069	122.2	153.8	3.5	107.5

Southeast	1803	33.5	112.2	-78.5	130.8

Central 	1672	18.1	81.0	-59.6	114.1

West	9522	-39.6	81.1	-104.0	131.1

Total Nitrate  (NO3+HNO3)	CASTNet	12-km EUS	3171	24.4	37.3	16.8	35.1

12-km WUS	1157	-19.5	44.2	-12.0	46.0

Northeast	662	20.5	29.4	16.3	25.3

Midwest	839	39.1	46.5	29.0	39.7

Southeast	1085	22.9	39.5	15.8	37.2

Central 	229	6.2	35.6	0.6	36.2

West	1117	-20.4	45.8	-12.1	46.6

Ammonium	STN	12-km EUS	10157	11.9	40.6	14.4	45.2

12-km WUS	2926	-23.6	55.7	7.2	58.1

Northeast	1488	16.0	39.6	21.8	42.8

Midwest	2731	12.3	38.4	19.2	42.4

Southeast	2540	7.3	38.4	6.0	41.8

Central 	2685	15.0	46.6	14.3	52.1

West	2446	-30.6	56.7	2.9	59.7

	CASTNet	12-km EUS	3166	5.3	30.8	2.7	31.6

12-km WUS	1156	-16.8	42.5	-13.0	41.1

Northeast	661	15.3	27.6	13.6	25.2

Midwest	837	9.8	34.7	11.9	33.9

Southeast	1085	-7.7	30.1	-9.7	33.6

Central 	229	7.4	33.1	3.0	35.6

West	1116	-21.1	43.5	-14.4	41.4

Elemental Carbon	STN	12-km EUS	10031	45.0	78.9	22.1	56.9

12-km WUS	2975	43.1	82.6	18.2	61.3

Northeast	1498	37.1	58.9	24.5	48.3

Midwest	2744	53.1	76.7	26.3	54.7

Southeast	2506	16.9	66.0	7.2	51.7

Central 	2570	91.7	118.0	41.0	68.1

West	2475	49.0	86.2	17.1	62.7

	IMPROVE	12-km EUS	8282	-15.0	49.2	-23.4	52.8

12-km WUS	10069	-14.1	67.2	-29.5	62.1

Northeast	599	-22.6	37.5	-27.4	46.5

Midwest	2056	11.6	57.5	0.5	50.8

Southeast	1795	-32.4	44.6	-42.0	55.6

Central 	1532	-24.3	47.6	-29.8	55.9

West	9493	-15.5	67.8	-31.3	62.7

Organic Carbon	STN	12-km EUS	9726	-39.9	58.0	-41.1	70.5

12-km WUS	2903	-37.6	60.3	-40.4	69.3

Northeast	1447	-45.2	60.9	-41.6	73.1

Midwest	2641	-26.5	61.7	-19.7	67.6

Southeast	2474	-47.4	55.3	-53.7	70.7

Central 	2504	-43.6	54.0	-51.3	69.7

West	2408	-36.3	61.4	-37.9	70.2

	IMPROVE	12-km EUS	8287	-32.4	60.5	-37.1	67.9

12-km WUS	10082	-34.8	60.0	-31.2	63.0

Northeast	598	-42.4	54.8	-40.2	63.8

Midwest	2057	-6.4	68.2	-0.7	60.8

Southeast	1800	-46.1	58.4	-69.7	81.3

Central	1531	-47.9	61.6	-61.2	79.6

West	9508	-34.5	59.6	-29.7	61.9

Figure 3-1.  Normalized Mean Bias (%) of annual PM2.5 by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-2.  Normalized Mean Error (%) of annual PM2.5 by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-3.  Normalized Mean Bias (%) of annual sulfate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-4.  Normalized Mean Error (%) of annual sulfate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-5.  Normalized Mean Bias (%) of annual nitrate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-6.  Normalized Mean Error (%) of annual nitrate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-7.  Normalized Mean Bias (%) of annual total nitrate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-8.  Normalized Mean Error (%) of annual total nitrate by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-9.  Normalized Mean Bias (%) of annual ammonium by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-10.  Normalized Mean Error (%) of annual ammonium by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-11.  Normalized Mean Bias (%) of annual EC by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-12.  Normalized Mean Error (%) of annual EC by monitor for 12-km Eastern U.S. domain. 2002.

Figure 3-13.  Normalized Mean Bias (%) of annual OC by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-14.  Normalized Mean Error (%) of annual OC by monitor for 12-km Eastern U.S. domain, 2002.

Figure 3-15.  Normalized Mean Bias (%) of annual PM2.5 by monitor for 12-km Western U.S. domain, 2002.

Figure 3-16.  Normalized Mean Error (%) of annual PM2.5 by monitor for 12-km Western U.S. domain, 2002.

Figure 3-17.  Normalized Mean Bias (%) of annual sulfate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-18.  Normalized Mean Error (%) of annual sulfate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-19.  Normalized Mean Bias (%) of annual nitrate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-20.  Normalized Mean Error (%) of annual nitrate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-21.  Normalized Mean Bias (%) of annual total nitrate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-22.  Normalized Mean Error (%) of annual total nitrate by monitor for 12-km Western U.S. domain, 2002.

Figure 3-23.  Normalized Mean Bias (%) of annual ammonium by monitor for 12-km Western U.S. domain, 2002.

Figure 3-24.  Normalized Mean Error (%) of annual ammonium by monitor for 12-km Western U.S. domain, 2002.

Figure 3-25.  Normalized Mean Bias (%) of annual EC by monitor for 12-km Western U.S. domain, 2002.

Figure 3-26.  Normalized Mean Error (%) of annual EC by monitor for 12-km Western U.S. domain, 2002.

Figure 3-27.  Normalized Mean Bias (%) of annual OC by monitor for 12-km Western U.S. domain, 2002.

Figure 3-28.  Normalized Mean Error (%) of annual OC by monitor for 12-km Western U.S. domain, 2002.

Seasonal PM2.5 Total Mass Performance

Seasonal model performance statistics for PM2.5 total mass are shown in Table 3-2.  Figures 3-29 to 3-44 depict spatial plots of the NMB and NME statistics (units of percent) for individual monitors.  Total PM2.5 mass is generally over-predicted in the cooler seasons (winter and fall) in the 12-km Eastern domain for both STN and IMPROVE networks.  In the fall season, PM2.5 is slightly over-predicted for Eastern STN and IMPROVE networks with NMB values ranging from 10% to 15% and FB values ranging from 6% to 9%.  In the winter season, PM2.5 is moderately over-predicted for Eastern STN and IMPROVE networks with NMB values ranging from 47% to 55% and FB values ranging from 60% to 72%.  In the 12-km Western domain, PM2.5 is over-predicted in the winter (NMB in the range of 2% to 14%), whereas PM2.5 is under-predicted in the fall (NMB in the range of -15% to -4%).  In the spring, CMAQ over-predicts PM2.5 in the East (NMB=15%) and West (NMB=4%) for urban STN sites.  However, PM2.5 is under-predicted for rural IMPROVE sites in the East (NMB= -2%) and West (NMB= -32%).  Note that for comparison of West versus East STN sites, the total number of Western sites is usually less than a third of the Eastern sites.  In the summer season, PM2.5 is under-predicted in the East and West for STN and IMPROVE.

Table 3-2.  CMAQ 2002 seasonal model performance statistics for PM2.5 total mass.

CMAQ 2002 PM2.5 total mass	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Winter	STN	12-km EUS	2185	47.1	60.1	34.5	50.0

12-km WUS	637	2.17	53.4	8.5	51.1

Northeast	299	32.6	45.2	31.1	43.4

Midwest	582	74.2	77.6	55.1	57.9

Southeast	527	24.5	45.9	15.0	42.2

Central 	619	51.6	66.2	36.0	53.6

West	534	-1.6	51.8	3.9	50.4

	IMPROVE	12-km EUS	2068	55.0	72.2	36.9	56.4

12-km WUS	2467	13.7	59.5	11.1	54.3

Northeast	148	35.7	46.7	25.1	41.3

Midwest	514	110.5	115.7	70.5	74.4

Southeast	450	22.3	46.7	13.3	46.0

Central 	381	31.5	57.9	21.9	53.8

West	2340	11.1	58.6	10.1	54.0

Spring	STN	12-km EUS	2452	15.3	46.2	6.9	42.8

12-km WUS	694	3.6	50.6	5.1	45.3

Northeast	366	31.1	51.7	20.6	41.0

Midwest	630	33.2	47.3	23.1	38.2

Southeast	628	-0.2	35.3	-5.9	36.8

Central 	652	4.1	52.5	-6.1	54.2

West	590	9.7	51.0	9.6	44.6

	IMPROVE	12-km EUS	1912	-1.7	46.9	-12.5	46.7

12-km WUS	2390	-31.7	50.3	-35.4	55.7

Northeast	147	33.1	56.3	8.2	43.4

Midwest	510	28.4	48.6	16.3	39.9

Southeast	440	-13.6	40.9	-22.6	47.3

Central 	289	-24.7	52.7	-38.8	61.0

West	2331	-30.4	49.7	-34.5	55.1

Summer	STN	12-km EUS	2798	-17.3	33.1	-22.3	40.7

12-km WUS	841	-22.9	37.9	-24.7	42.6

Northeast	418	-6.3	24.9	-7.6	27.6

Midwest	780	-18.6	33.5	-16.3	36.1

Southeast	698	-24.2	34.2	-34.1	43.9

Central 	713	-13.4	37.0	-21.3	47.8

West	688	-23.0	39.4	-24.8	43.9

	IMPROVE	12-km EUS	2160	-38.1	42.9	-52.5	58.9

12-km WUS	2572	-46.5	55.0	-60.8	68.0

Northeast	149	-25.3	32.1	-36.7	43.1

Midwest	516	-33.7	40.3	-35.4	47.5

Southeast	454	-37.5	42.4	-55.8	62.1

Central 	440	-43.0	45.5	-65.1	68.0

West	2412	-46.3	55.5	-60.1	67.7

Fall	STN	12-km EUS	2872	15.5	39.0	9.2	38.6

12-km WUS	828	-4.1	46.4	3.2	42.6

Northeast	433	16.4	29.7	14.7	29.3

Midwest	788	26.9	46.6	15.4	41.3

Southeast	701	-2.1	32.0	-8.6	36.4

Central 	754	25.2	46.0	17.8	43.2

West	675	-10.1	45.2	-2.6	41.7

	IMPROVE	12-km EUS	2296	9.6	42.5	5.6	43.6

12-km WUS	2694	-15.8	50.7	-19.5	52.1

Northeast	148	20.1	39.1	13.3	36.1

Midwest	520	23.8	48.6	18.5	44.4

Southeast	459	-3.3	35.3	-14.0	44.0

Central 	514	8.6	47.2	5.6	47.6

West	2460	-20.9	49.4	-23.2	51.9

Figure 3-29.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-30.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-31.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-32.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-33.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-34.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Eastern U.S. domain. Summer 2002.

Figure 3-35.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-36.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-37.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-38.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-39.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-40.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-41.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-42.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-43.  Normalized Mean Bias (%) of PM2.5 by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-44.  Normalized Mean Error (%) of PM2.5 by monitor for 12-km Western U.S. domain, Fall 2002.

Seasonal Sulfate Performance

As seen in Table 3-3, CMAQ generally under-predicts sulfate in the 12-km Eastern and Western domains throughout the entire year.  Figures 3-45 – 3-60 show spatial plots of the NMB and NME statistics (units of percent) for individual monitors as a complement to the tabular statistical data.  Sulfate predictions during the winter season show NMB values ranging from -7% to -18% and FB values ranging from 6% to -17% in the East and with NMB values ranging from -8% to -33% and FB values ranging from 0.3% to -41% in the West.  Sulfate predictions during the fall seasons are nearly unbiased in the East, with NMB values ranging from 3% to -10% across STN, IMPROVE, and CASTNet networks.  Sulfate is moderately under-predicted in the West during the fall season (NMB values ranging from 11% to 22%).  In the spring, sulfate predictions are somewhat under-predicted in the East and West, with NMB values ranging from -4% to -18%.  Sulfate predictions during the summer season are slightly under-predicted in the East across the available monitoring data, while sulfate predictions in the West were moderately under-predicted.

Table 3-3.  CMAQ 2002 seasonal model performance statistics for sulfate.

CMAQ 2002 Sulfate	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Winter	STN	12-km EUS	2155	-6.8	35.1	-8.8	38.6

12-km WUS	633	-8.5	49.2	0.3	47.4

Northeast	286	-6.8	34.6	-12.0	37.1

Midwest	575	-4.1	29.3	-6.7	30.4

Southeast	523	-16.0	34.9	-22.7	41.1

Central 	614	0.9	43.2	1.5	45.2

West	531	-14.4	49.1	-5.6	46.8

	IMPROVE	12-km EUS	2073	-8.1	36.2	6.4	45.7

12-km WUS	2484	33.5	61.1	41.5	58.3

Northeast	149	-17.4	35.3	-24.3	40.1

Midwest	514	-9.3	30.1	-9.6	32.8

Southeast	447	-13.5	31.5	-15.2	38.2

Central 	383	-10.0	39.7	0.8	45.2

West	2356	36.1	63.6	42.2	58.9

	CASTNet	12-km EUS	711	-17.8	25.3	-17.5	30.4

12-km WUS	253	11.4	37.3	21.4	37.5

Northeast	154	-23.3	29.3	-31.6	35.8

Midwest	184	-16.9	22.2	-20.0	26.4

Southeast	249	-15.7	23.2	-16.9	25.8

Central 	41	-19.2	25.8	-21.7	30.2

West	249	12.8	38.4	21.8	37.8

Spring	STN	12-km EUS	2396	-13.4	35.5	-16.5	38.8

12-km WUS	667	-14.5	37.3	-2.6	37.3

Northeast	362	-2.7	39.1	-8.7	39.5

Midwest	609	-5.4	34.7	-10.7	34.8

Southeast	624	-18.2	32.1	-20.1	36.3

Central 	626	-21.1	39.2	-22.2	45.0

West	586	-14.6	38.4	-2.6	37.8

	IMPROVE	12-km EUS	1946	-16.0	32.9	-15.0	38.0

12-km WUS	2412	-4.3	38.8	8.3	40.6

Northeast	147	-10.7	30.2	-13.9	34.3

Midwest	512	-10.5	32.7	-14.1	36.3

Southeast	441	-16.1	30.6	-20.2	37.1

Central 	307	-29.8	36.9	-33.9	44.4

West	2350	-1.8	38.7	9.6	40.4

	CASTNet	12-km EUS	784	-17.6	23.4	-20.4	27.1

12-km WUS	289	-18.2	29.8	-12.3	30.3

Northeast	169	-13.5	20.6	-17.0	23.8

Midwest	203	-13.2	20.2	-16.7	22.5

Southeast	267	-20.8	24.7	-24.6	29.1

Central 	55	-37.8	38.3	-43.9	45.3

West	280	-16.9	29.6	-11.5	30.1

Summer	STN	12-km EUS	2768	1.6	31.4	-3.6	37.8

12-km WUS	805	-27.7	40.5	-25.1	45.6

Northeast	414	15.3	34.8	13.2	33.8

Midwest	770	-1.1	26.8	1.0	32.7

Southeast	697	0.7	33.1	-6.9	37.8

Central 	701	-3.3	35.3	-13.0	46.3

West	660	-35.4	46.8	-28.4	48.9

	IMPROVE	12-km EUS	2208	-11.1	32.0	-13.6	41.0

12-km WUS	2639	-21.0	41.1	-14.8	43.3

Northeast	152	0.9	28.2	1.6	35.7

Midwest	526	-13.4	29.6	-1.3	39.8

Southeast	456	-7.9	33.6	-17.8	43.8

Central	461	-17.1	33.4	-27.5	45.3

West	2475	-19.4	42.1	-13.3	43.0

	CASTNet	12-km EUS	868	-6.8	17.6	-12.9	22.9

12-km WUS	313	-32.5	37.9	-32.5	41.4

Northeast	176	-0.03	16.0	-1.2	16.1

Midwest	233	-10.5	16.1	-12.3	19.0

Southeast	298	-6.6	18.6	-14.5	26.8

Central 	68	-15.3	23.5	-22.4	31.1

West	299	-33.1	39.4	-32.6	41.9

Fall	STN	12-km EUS	2838	-2.7	34.5	-10.6	38.6

12-km WUS	821	-22.4	42.8	-17.1	43.5

Northeast	425	-4.0	32.1	-7.5	35.2

Midwest	776	-9.6	28.4	-18.7	36.0

Southeast	697	-5.3	34.1	-17.4	40.4

Central	745	9.7	41.9	3.8	40.9

West	669	-30.5	44.8	-23.0	45.3

	IMPROVE	12-km EUS 	2305	-7.4	32.6	-6.6	38.1

12-km WUS	2697	-11.4	38.6	-2.4	41.0

Northeast	149	-2.4	29.3	-3.6	32.6

Midwest	518	-14.4	28.4	-14.8	35.4

Southeast	461	-3.3	34.8	-14.1	42.6

Central 	520	-8.2	34.2	-7.6	36.7

West	2464	-11.6	39.9	-2.4	41.5

	CASTNet	12-km EUS	810	-9.6	20.0	-14.8	24.6

12-km WUS	303	-21.8	33.3	-15.6	34.2

Northeast	164	-10.2	18.0	-17.6	22.9

Midwest	219	-12.0	16.7	-14.6	19.5

Southeast	271	-7.1	22.2	-15.3	27.1

Central 	65	-14.9	24.1	-22.4	28.3

West	290	-21.5	34.1	-15.2	34.4

Figure 3-45.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-46.  Normalized Mean Error (%) of sulfate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-47.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-48.  Normalized Mean Error (%) of sulfate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-49.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-50.  Normalized Mean Error (%) of sulfate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-51.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-52.  Normalized Mean Error (%) of sulfate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-53.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-54.  Normalized Mean Error (%) of sulfate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-55.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-56.  Normalized Mean Error (%) of sulfate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-57.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-58.  Normalized Mean Error (%) of sulfate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-59.  Normalized Mean Bias (%) of sulfate by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-60.  Normalized Mean Error (%) of sulfate by monitor for 12-km Western U.S. domain, Fall 2002.

Seasonal Nitrate and Total Nitrate Performance

Table 3-4 provides the seasonal model performance statistics for nitrate and total nitrate for the 12-km Eastern and Western domains.  Spatial plots of the NMB and NME statistics (units of percent) for individual monitors are also provided (Figures 3-61 – 3-92).  Overall, nitrate and total nitrate performance is over-predicted in the EUS and under-predicted in the WUS for all of the seasonal assessments except the summer season, where nitrate is under-predicted in the EUS and WUS.  In the East, nitrate and total nitrate is moderately over-predicted during the winter season when nitrate is most abundant (NMB values ranging from 26% to 50%).  In the West, during the winter, nitrate performance is moderately under-predicted (NMB ~40%) and total nitrate performance slightly under-predicted (NMB ~5%).  Nitrate and total nitrate performance is mixed for the fall and spring seasons, with moderate under-predictions occurring in the West and moderate over-predictions occurring in the East.

Table 3-4.  CMAQ 2002 seasonal model performance statistics for nitrate and total nitrate.

CMAQ 2002 Nitrate 	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Nitrate   (Winter)	STN	12-km EUS	1835	24.7	56.3	17.2	61.7

12-km WUS	600	-45.1	59.7	-54.0	81.5

Northeast	287	7.2	43.0	10.6	50.4

Midwest	575	50.3	62.2	44.4	58.1

Southeast	523	39.3	83.1	5.1	79.2

Central 	293	0.7	42.1	11.0	48.6

West	531	-48.2	59.3	-62.9	83.8

	IMPROVE	12-km EUS	2060	50.1	95.6	-15.1	102

12-km WUS	2371	-38.6	73.9	-97.1	127.2

Northeast	149	5.3	50.2	-16.0	75.8

Midwest	514	145.3	155.5	85.2	95.3

Southeast	447	33.7	90.7	-30.7	101.6

Central 	383	8.8	67.9	-14.6	89.9

West	2243	-42.2	76.5	-101.5	129.8

Total Nitrate  (Winter)	CASTNet	12-km EUS	710	25.8	34.8	28.0	35.5

12-km WUS	253	-5.3	39.9	10.8	43.8

Northeast	153	2.6	16.9	5.1	17.1

Midwest	184	51.8	52.6	45.6	46.1

Southeast	249	34.1	40.9	31.0	37.7

Central 	41	29.0	49.6	26.8	41.7

West	249	-3.2	41.2	11.3	44.1

Nitrate   (Spring)	STN	12-km EUS	2094	43.2	82.6	-3.7	78.8

12-km WUS	643	-30.6	59.9	-44.4	78.0

Northeast	362	56.0	88.6	24.4	68.0

Midwest	609	42.4	77.9	12.9	68.9

Southeast	624	36.3	107.4	-39.1	100.9

Central 	324	38.4	65.7	5.5	69.0

West	586	-32.0	59.2	-43.6	75.7

	IMPROVE	12-km EUS	1947	89.1	140.9	-24.5	106.1

12-km WUS	2409	-22.6	79.1	-79.7	113.4

Northeast	147	143.3	175.1	3.0	108.9

Midwest	512	149.0	175.6	35.0	96.6

Southeast	442	63.9	141.2	-66.1	130.8

Central 	307	54.8	113.0	-58.5	114.4

West	2347	-22.3	79.1	-79.3	113.0

Total Nitrate  (Spring)	CASTNet	12-km EUS	784	28.0	42.1	16.1	35.1

12-km WUS	289	-13.2	38.1	-6.2	39.3

Northeast	169	39.7	44.0	26.5	31.4

Midwest	203	42.5	47.6	31.4	37.4

Southeast	267	11.2	36.6	5.7	34.0

Central 	55	-3.1	38.0	-7.3	43.3

West	280	-12.4	39.6	-5.6	39.7

Nitrate   (Summer)	STN	12-km EUS	2392	-31.7	74.4	-85.7	110.4

12-km WUS	736	-61.1	69.0	-121.9	128.1

Northeast	414	-11.3	78.2	-42.9	91.2

Midwest	770	-27.1	71.4	-71.2	101.4

Southeast	697	-66.5	77.5	-126.2	133.9

Central 	325	-29.7	65.7	-62.9	89.3

West	660	-61.2	69.0	-122.3	128.6

	IMPROVE	12-km EUS	2203	-43.8	95.3	-125.9	143.9

12-km WUS	2631	-73.3	88.6	-155.4	161.7

Northeast	152	-28.4	87.6	-98.1	126

Midwest	526	-7.2	108.3	-98.1	128.8

Southeast	454	-41.6	107.5	-130.0	153.9

Central 	461	-68.6	82.7	-135.1	144.3

West	2467	-72.8	88.7	-155.8	162.1

Total Nitrate  (Summer)	CASTNet	12-km EUS	868	4.3	27.2	-4.8	30.5

12-km WUS	313	-36.3	46.3	-42.3	54.0

Northeast	176	9.3	23.3	4.6	21.8

Midwest	233	9.4	28.8	0.6	29.3

Southeast	298	3.5	29.6	-2.1	33.7

Central 	68	-18.4	27.2	-24.5	32.5

West	299	-37.6	47.6	-43.0	54.8

Nitrate        (Fall)	STN	12-km EUS	2449	13.9	59.9	-30.3	81.2

12-km WUS	747	-44.6	65.9	-56.1	87.9

Northeast	425	11.4	41.6	-3.7	55.0

Midwest	777	33.8	76.2	-10.5	77.1

Southeast	696	-8.8	73.1	-78.6	108.3

Central 	356	20.6	51.3	-5.5	67.6

West	669	-48.0	65.6	-61.0	89.1

	IMPROVE	12-km EUS	2304	53.1	100.5	-40.4	111.6

12-km WUS	2699	-16.0	84.3	-70.3	116.4

Northeast	149	42.8	66.9	-35.1	100.2

Midwest	517	112.7	151.1	-5.5	108.8

Southeast	460	43.3	121.7	-85.8	136.5

Central 	521	41.1	81.0	-26.6	104.9

West	2465	-29.3	82.7	-77.7	118.5

Total Nitrate  (Fall)	CASTNet	12-km EUS	809	41.0	46.3	30.9	39.8

12-km WUS	302	-12.2	49.6	-5.4	45.9

Northeast	164	35.9	37.1	29.0	30.1

Midwest	219	55.9	59.3	43.1	47.3

Southeast	271	42.3	51.3	31.4	43.7

Central 	65	23.0	31.8	17.1	30.5

West	289	-15.6	51.7	-6.7	46.9

Figure 3-61.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-62.  Normalized Mean Error (%) of nitrate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-63.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-64.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-65.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-66.  Normalized Mean Error (%) of nitrate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-67.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-68.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-69.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-70.  Normalized Mean Error (%) of nitrate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-71.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-72.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-73.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-74.  Normalized Mean Error (%) of nitrate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-75.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-76.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-77.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-78.  Normalized Mean Error (%) of nitrate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-79.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-80.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-81.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-82.  Normalized Mean Error (%) of nitrate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-83.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-84.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-85.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-86.  Normalized Mean Error (%) of nitrate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-87.  Normalized Mean Bias (%) of total nitrate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-88.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-89.  Normalized Mean Bias (%) of nitrate by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-90.  Normalized Mean Error (%) of nitrate by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-91.  Normalized Mean Bias (%) of total nitrate by monitor for  12-km Western U.S. domain, Fall 2002.

Figure 3-92.  Normalized Mean Error (%) of total nitrate by monitor for 12-km Western U.S. domain, Fall 2002.

Seasonal Ammonium Performance

Table 3-5 lists the performance statistics for ammonium PM at the STN and CASTNet sites.  Figures 3-93 – 3-108 show spatial plots of the NMB and NME statistics (units of percent) for individual monitors.  In the winter, ammonium performance varies across the EUS and WUS, with STN and CASTNet networks showing an over-prediction in the East (NMB values range from 17% to 27) and an under-prediction in the West (NMB values range from -27% to -11%).   Likewise, ammonium performance for the fall and spring season in the East and West is similar to that of the winter season.  However, in the summer, model predictions in the EUS are near negligible at STN sites and under-predicted at CASTNet sites.  Ammonium predictions in the summer are moderately under-predicted for the West in both the rural and urban sites (NMB ~ 28%).

Table 3-5.  CMAQ 2002 seasonal model performance statistics for ammonium.

CMAQ 2002 Ammonium	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Winter	STN	12-km EUS	2156	27.2	47.3	29.7	49.8

12-km WUS	633	-26.8	59.1	9.6	72.7

Northeast	287	10.6	35.6	18.8	41.1

Midwest	575	34.6	44.8	37.5	44.6

Southeast	523	29.3	52.3	20.8	48.7

Central 	614	31.9	57.0	35.9	58.7

West	531	-33.8	57.2	1.2	72.4

	CASTNet	12-km EUS	711	16.7	31.1	16.1	31.2

12-km WUS	253	-11.1	44.1	-7.5	43.0

Northeast	154	-0.1	19.3	3.2	20.8

Midwest	184	49.3	51.3	43.0	44.5

Southeast	249	12.7	29.4	9.3	27.5

Central 	41	20.6	41.3	13.7	40.7

West	249	-13.9	45.5	-8.0	43.1

Spring	STN	12-km EUS	2396	16.9	44.2	12.5	43.4

12-km WUS	667	-6.1	54.0	22.5	54.0

Northeast	362	34.6	57.6	26.7	47.2

Midwest	609	17.4	39.2	18.1	37.0

Southeast	624	11.4	38.6	9.3	40.4

Central 	626	9.5	45.7	1.0	50.5

West	586	-8.9	54.9	22.7	55.2

	CASTNet	12-km EUS	777	24.2	40.4	13.2	33.3

12-km WUS	287	-6.1	38.0	-3.1	33.3

Northeast	167	48.6	52.8	32.7	37.7

Midwest	201	29.7	38.5	22.0	31.3

Southeast	267	2.4	30.5	-0.7	31.3

Central 	55	3.2	41.5	-3.3	39.7

West	278	-9.8	37.0	-4.3	33.1

Summer	STN	12-km EUS	2768	1.0	35.0	6.1	43.8

12-km WUS	805	-29.1	48.3	-6.0	49.7

Northeast	414	13.9	36.4	21.2	43.1

Midwest	770	-4.1	33.2	12.4	42.7

Southeast	697	0.5	33.8	1.4	39.3

Central 	701	0.7	38.2	-2.8	50.0

West	660	-36.3	54.1	-8.6	54.0

	CASTNet	12-km EUS	868	-11.8	25.3	-17.4	31.3

12-km WUS	313	-26.0	40.6	-27.8	44.8

Northeast	176	5.5	20.3	5.2	20.6

Midwest	233	-17.2	25.5	-18.9	29.4

Southeast	298	-22.1	29.2	-31.2	39.9

Central 	68	-1.1	24.2	-5.9	30.4

West	299	-30.0	43.3	-29.6	45.6

Fall	STN	12-km EUS	2837	9.0	39.0	12.7	44.6

12-km WUS	821	-25.8	58.9	5.9	58.2

Northeast	425	8.2	32.5	20.4	40.0

Midwest	777	11.7	39.4	13.4	44.6

Southeast	696	-1.23	35.0	-3.7	40.2

Central U.S.	744	20.9	47.8	23.6	49.9

West	669	-35.5	59.0	-1.8	59.0

	CASTNet	12-km EUS	810	4.0	29.7	2.4	30.7

12-km WUS	303	-18.1	48.0	-11.6	43.3

Northeast	164	13.8	22.8	13.1	21.7

Midwest	219	7.3	34.1	9.3	32.2

Southeast	271	-9.2	31.6	-12.3	34.6

Central	65	14.9	34.1	10.9	34.4

West	290	-24.9	48.7	-13.7	43.5

Figure 3-93.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure  3-94.  Normalized Mean Error (%) of ammonium by monitor for  12-km Eastern U.S. domain, Winter 2002.

Figure 3-95.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-96.  Normalized Mean Error (%) of ammonium by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-97.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-98.  Normalized Mean Error (%) of ammonium by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-99.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-100.  Normalized Mean Error (%) of ammonium by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-101.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-102.  Normalized Mean Error (%) of ammonium by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-103.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-104.  Normalized Mean Error (%) of ammonium by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-105.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-106.  Normalized Mean Error (%) of ammonium by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-107.  Normalized Mean Bias (%) of ammonium by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-108.  Normalized Mean Error (%) of ammonium by monitor for 12-km Western U.S. domain, Fall 2002.

Seasonal Elemental Carbon Performance

Table 3-6 presents the seasonal performance statistics of elemental carbon for the urban and rural 2002 monitoring data.  Likewise, NMB and NME spatial plots (units of percent) for individual monitors are also provided in Figures 3-109 – 3-124.  In the winter, elemental carbon performance is mixed across the STN and IMPROVE networks, with a slight over-prediction in the East (NMB=10%) and slight under-prediction in the West (NMB= -7%) for IMPROVE and a moderate over-prediction in the East (NMB=64%) and in the West (NMB= -36%).  Nationally, elemental carbon predictions are moderately over-predicted for the fall, spring and summer seasons for STN, however, elemental carbon is generally under-predicted for the East and West at IMPROVE.  These biases and errors are not unexpected since there are known uncertainties among the scientific community in carbonaceous emissions/measurements, transport, and deposition processes.

Table 3-6.  CMAQ 2002 seasonal model performance statistics for elemental carbon.

CMAQ 2002 Elemental Carbon	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Winter	STN	12-km EUS	2136	64.3	93.4	38.7	63.2

12-km WUS	629	35.8	83.8	13.6	63.7

Northeast	297	72.9	87.9	50.2	61.1

Midwest	574	89.3	98.3	54.7	63.7

Southeast	524	23.7	65.1	16.0	50.6

Central 	585	99.2	132.9	49.9	74.7

West	529	43.6	85.4	12.4	63.1

	IMPROVE	12-km EUS	2033	10.4	53.4	-0.6	51.4

12-km WUS	2429	-7.4	70.5	-33.7	68.7

Northeast	149	-0.8	31.8	6.0	32.8

Midwest	512	56.2	70.2	40.8	53.6

Southeast	439	-18.7	41.4	-23.2	47.1

Central 	368	-8.6	49.9	-8.6	50.7

West	2303	-10.1	70.5	-36.6	69.5

Spring	STN	12-km EUS	2360	42.2	78.8	16.1	56.2

12-km WUS	687	57.3	95.4	15.6	64.0

Northeast	364	23.2	56.7	7.6	47.8

Midwest	618	46.8	75.1	21.0	53.9

Southeast	600	13.4	63.5	1.7	49.6

Central 	603	96.7	122.4	37.5	68.2

West	588	64.2	101.2	15.9	66.0

	IMPROVE	12-km EUS	1920	-13.4	44.4	-20.1	46.2

12-km WUS	2369	-2.6	62.4	-16.6	51.6

Northeast	147	-22.4	34.3	-29.2	42.6

Midwest	510	19.3	51.5	4.2	45.5

Southeast	443	-30.1	43.0	-36.5	49.6

Central 	293	-37.7	42.5	-47.4	55.6

West	2307	-1.1	63.0	-16.0	51.5

Summer	STN	12-km EUS	2725	38.9	71.88	18.8	54.2

12-km WUS	834	54.8	82.7	24.6	58.0

Northeast	412	29.9	48.8	22.3	43.1

Midwest	771	35.8	62.0	21.4	48.3

Southeast	688	14.4	69.0	5.4	53.4

Central 	666	97.7	119.2	37.9	67.9

West	686	63.1	89.6	25.0	60.5

	IMPROVE	12-km EUS	2127	-40.0	52.2	-49.5	62.6

12-km WUS	2590	-22.8	65.5	-29.5	60.1

Northeast	153	-44.7	46.8	-65.3	68.5

Midwest	523	-31.1	53.8	-38.8	57.5

Southeast	456	-49.9	52.7	-62.9	69.0

Central 	409	-44.6	50.8	-53.6	67.4

West	2430	-22.7	66.8	-29.9	60.8

Fall	STN	12-km EUS	2810	35.2	72.3	17.7	55.4

12-km WUS	825	35.0	75.2	17.4	60.7

Northeast	425	29.7	50.4	23.1	44.7

Midwest	781	40.2	71.5	14.4	55.0

Southeast	694	15.4	66.4	70.0	52.6

Central 	716	76.8	100.4	39.3	62.7

West	672	37.1	77.2	13.9	61.5

	IMPROVE	12-km EUS	2202	-13.4	45.1	-22.0	50.5

12-km WUS	2681	-15.1	69.7	-36.9	67.3

Northeast	150	-13.9	33.1	-20.0	41.4

Midwest	511	7.4	51.7	-3.5	46.3

Southeast	457	-32.9	41.6	-44.4	56.1

Central 	462	-7.8	46.32	-14.4	50.0

West	2453	-19.3	70.1	-42.1	68.8

Figure 3-109.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-110.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-111.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-112.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-113.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-114.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-115.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-116.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-117.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-118.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-119.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-120.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-121.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-122.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-123.  Normalized Mean Bias (%) of elemental carbon by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-124.  Normalized Mean Error (%) of elemental carbon by monitor for 12-km Western U.S. domain, Fall 2002.

Seasonal Organic Carbon Performance

Seasonal organic carbon performance statistics are provided in Table 3-7.  Spatial plots of NMB and NME (units of percent) for individual monitors are also provided in Figures 3-125 – 3-140.  The model predictions generally show moderate under-predictions for all Eastern sites located in the urban STN sites (NMB values range from -12% to -67%) and rural IMPROVE sites (NMB values range from -3% to -50%).   Organic carbon performance in the EUS and WUS shows the largest under estimations during the summer season.  For IMPROVE, organic carbon performance shows a negative bias in the West (NMB= -3%) and a positive bias in the East (NMB=24%).  For STN, organic carbon is under-predicted in the East (NMB= -12%) and West (NMB= -26%).  These biases and errors reflect sampling artifacts among each monitoring network.  In addition, uncertainties exist for primary organic mass emissions and secondary organic aerosol formation.  Research efforts are ongoing to improve fire emission estimates and understand the formation of semi-volatile compounds, and the partitioning of SOA between the gas and particulate phases.

Table 3-7.  CMAQ 2002 seasonal model performance statistics for organic carbon.

CMAQ 2002 Organic Carbon	No. of Obs.	NMB (%)	NME (%)	FB (%)	FE (%)

	Winter	STN	12-km EUS	2063	-12.4	51.2	-2.5	55.2

12-km WUS	606	-25.6	62.0	-22.4	62.6

Northeast	284	-18.1	58.7	-0.7	62.7

Midwest	552	24.4	61.6	34.0	60.4

Southeast	520	-32.4	44.0	-27.8	51.5

Central 	568	-22.9	45.4	-13.2	48.5

West	507	-24.2	63.0	-22.0	64.3

	IMPROVE	12-km EUS	2032	24.5	65.4	14.1	55.4

12-km WUS	2432	-2.9	59.9	-4.3	58.9

Northeast	149	4.6	43.1	16.6	45.0

Midwest	512	89.2	104.2	63.5	71.9

Southeast	439	-12.9	42.9	-22.1	49.9

Central 	366	-5.1	52.9	-4.5	51.4

West	2307	-4.8	59.3	-5.1	59.4

Spring	STN	12-km EUS	2241	-19.1	53.6	-15.7	60.8

12-km WUS	656	-19.8	63.4	-13.7	64.5

Northeast	337	-19.9	57.1	-6.6	63.8

Midwest	583	8.5	55.3	9.8	55.8

Southeast	590	-25.9	47.5	-22.7	54.0

Central 	579	-38.7	53.2	-45.7	68.3

West	560	-15.9	65.9	-7.1	65.5

	IMPROVE	12-km EUS	1917	-27.2	53.0	-32.0	58.5

12-km WUS	2369	-23.7	54.5	-26.4	56.3

Northeast	147	-29.7	43.9	-28.6	52.1

Midwest	508	15.6	46.4	8.5	45.0

Southeast	442	-42.8	58.3	-60.6	73.0

Central 	293	-53.9	59.6	-71.6	81.0

West	2307	-21.5	53.6	-24.4	55.1

Summer	STN	12-km EUS	2690	-67.5	69.4	-95.0	100.3

12-km WUS	832	-55.4	60.0	-76.2	83.6

Northeast	408	-69.2	69.8	-98.4	101.2

Midwest	754	-68.1	71.5	-88.4	97.7

Southeast	683	-68.7	69.5	-100.9	104.5

Central	659	-63.3	64.9	-91.1	95.7

West	684	-54.0	59.3	-73.3	81.8

	IMPROVE	12-km EUS	2133	-66.7	69.0	-95.5	99.0

12-km WUS	2595	-50.4	63.7	-61.9	76.0

Northeast	153	-70.4	70.7	-103.1	104.0

Midwest	523	-66.2	68.5	-73.8	80.0

Southeast	460	-73.8	74.8	-122.3	123.2

Central 	411	-74.2	74.5	-120.0	120.7

West 	2435	-49.4	63.2	-58.1	73.0

Fall	STN	12-km EUS	2732	-37.6	50.2	-37.8	60.6

12-km WUS	809	-40.4	57.9	-38.7	63.4

Northeast	418	-44.1	51.3	-42.0	60.1

Midwest	752	-14.6	45.4	-13.2	51.9

Southeast	681	-47.6	52.3	-53.1	65.9

Central 	698	-43.7	50.7	-49.2	63.5

West	657	-41.0	59.9	-39.6	66.8

	IMPROVE	12-km EUS	2205	-25.5	47.2	-32.4	57.6

12-km WUS	2686	-29.4	56.5	-30.0	59.9

Northeast	149	-41.0	44.6	-44.0	53.0

Midwest	514	4.1	43.9	0.5	45.9

Southeast	459	-43.6	50.8	-71.3	77.4

Central 	461	-37.8	51.8	-47.2	64.6

West	2459	-29.9	56.4	-29.5	59.5

Figure 3-125.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-126.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Winter 2002.

Figure 3-127.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-128.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Spring 2002.

Figure 3-129.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-130.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Summer 2002.

Figure 3-131.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-132.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Eastern U.S. domain, Fall 2002.

Figure 3-133.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-134.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Western U.S. domain, Winter 2002.

Figure 3-135.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-136.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Western U.S. domain, Spring 2002.

Figure 3-137.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-138.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Western U.S. domain, Summer 2002.

Figure 3-139.  Normalized Mean Bias (%) of organic carbon by monitor for 12-km Western U.S. domain, Fall 2002.

Figure 3-140.  Normalized Mean Error (%) of organic carbon by monitor for 12-km Western U.S. domain, Fall 2002.

See EPA/OAQPS Air Quality Modeling Platform for the Ozone National Ambient Air Quality Standard Final Rule Regulatory Impact Analysis (Figure II-1) for the map of the CMAQ modeling domain.

 The subregions are defined by States where: Midwest is IL, IN, MI, OH, and WI; Northeast is CT, DE,

MA, MD, ME, NH, NJ, NY, PA, RI, and VT; Southeast is AL, FL, GA, KY, MS, NC, SC, TN, VA, and

WV; Central is AR, IA, KS, LA, MN, MO, NE, OK, and TX; West is AK, CA, OR, WA, AZ, NM, CO, UT, WY, SD, ND, MT, ID, and NV.

 Gilliam, R. C., W. Appel, and S. Phillips. The Atmospheric Model Evaluation Tool (AMET): Meteorology Module. Presented at 4th Annual CMAS Models-3 Users Conference, Chapel Hill, NC, September 26 - 28, 2005.

 See: U.S. Environmental Protection Agency; Technical Support Document for the Final Clean Air Interstate Rule: Air Quality Modeling; Office of Air Quality Planning and Standards; RTP, NC; March 2005 (CAIR Docket OAR-2005-0053-2149); and U.S. Environmental Protection Agency, 2006. Technical Support Document for the Final PM NAAQS Rule: Office of Air Quality Planning and Standards, Research Triangle Park, NC

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