1

Modeling Committee Update

OTC Air Directors’ Meeting 

April 24th, 2012

Washington, DC
2

Overview

1. Impact of NAAQS schedules

2. Progress made: design value (DV) update

3. Work left: nonattainment area projections

4. How do we proceed with screening runs? 
3

Ozone Standard Timelines

3/2008 Standard Final

3/2010 Expected Final Designation 

Date

5/2012 Final Designations

7 or 12/2015 SIPs Due/Clean Data for 

Marginal Nonattainment Areas

7 or 12/2018 Clean Data for Moderate 

Nonattainment Areas

3/2015 Standard Final

3/2017 Final Designations

5/2020 SIPs Due/Clean Data for Marginal 

Nonattainment Areas

5/2023 Clean Data for Moderate 

Nonattainment Areas

2008 - 75ppb Standard Future Standard Review

2008 standard faced delay in designations of 26 months.

Additional delays of 17-22 months could push designations until after clean 

data is required for moderate nonattainment areas for 2008 std. 

Based on EPA’s schedule with a 3 month 

delay due to 3rd CASAC review.
4

8-Hour Ozone Trends in OTR

8-Hour Ozone Exceedance Days in the OTR

52

78

71

37

54

67

34

30

48

36

48

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Number of Days

85ppb

1997 8-Hour O3 NAAQS of 85ppb

8-Hour Ozone Exceedance Days in the OTR

52

78

71

37

54

67

34

30

48

36

48

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Number of Days

85ppb

1997 8-Hour O3 NAAQS of 85ppb

Steady Progress 

Being made in 

the OTR

8-Hour Ozone Exceedance Days in the OTR

Number of Days

8-Hour Ozone Exceedance Days in the OTR

52

78

71

37

54

67

34

30

48

36

48

55

29

67

45

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Number of Days

85ppb 75ppb

1997 8-Hour O3 NAAQS of 85ppb 2008 8-Hour O3 - 75ppb

84ppb 75ppb If 65ppb

8-Hour Ozone Exceedance Days in the OTR

52

78

71

37

54

67

34

30

48

36

48

55

29

67

45

108

83

119

95

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Number of Days

85ppb 75ppb If 65ppb

1997 8-Hour O3 NAAQS of 85ppb 2008 8-Hour O3 - 75ppb

If a 65ppb O3 NAAQS 

was promulgated

8-Hour Ozone Exceedance Days in the OTR

52

78

71

37

54

67

34 30

48

36

48

55

29

67

45

131 135 133 133 137

130

123 121

130 125

107 109 115 114

153

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

199719981999200020012002200320042005200620072008200920102011

Number of Days

0

20

40

60

80

100

120

140

160

180

Concentration (ppb)

85ppb 75ppb If 65ppb Max Concentration

1997 8-Hour O3 NAAQS of 85ppb 2008 8-Hour O3 - 

140

120

100

80

60

40

20

0

1997 1999 2001 2003 2005 2007 2009 2011

180

160

140

120

100

80

60

40

20

0

Max Concentration
5

Annual 4th High Ozone Values

for the 3 Design Value Years – 2009, 2010 and 2011

5

Grey shaded area 

highlights general 

areas greater than 

75 ppb ozone

Parts per 

Billion 

(ppb)

<71

71-73

74-75

76-85

>85

Data is Preliminary
6

Preliminary 2011 Ozone Design Values

3-year average of 

the 4th high 

concentration for

2009, 2010, 2011

Projected 

nonattainment areas 

in the OTR
7

How DVs Changed From 2010 to 2011

Increase

Decrease

Ozone throughout 

most of the OTR 

improved

Except for the 

heart of the 

corridor
8

Eastern U.S. Counties Proposed or 

Potential Ozone Designation (2010DV)

Areas shaded in 

black represent 

locations where 

the preliminary 

2011 DVs exceed 

75ppb (but the 

2010DV did not)

Unclassified/Attainment

EPA Proposed Nonatt.

EPA Proposed Partial Nonatt.
9

CMSA/MSAs DV Analysis

• The MSA is in attainment with 2010 DV

• 1 or more monitors with 2011 DV > 75ppb

• State that impact OTR at 75ppb*

Louisville/Jefferson County, KY-IN: 78ppb

Dayton-Springfield-Greenville, OH: 76ppb

Detroit-Warren-Flint, MI: 78ppb, 76ppb

Grand Rapids-Muskegon-Holland, MI: 78ppb, 76ppb

Manitowoc, WI: 77ppb

Kansas City, MO-KS: 76ppb

*Based on NESCAUM’s analysis of the impact of states on nonattainment in 

the OTR using CSAPR modeling results
10

Hypothetical 2012 Design Values

• Hypothetical projection of a 2012 design value is made 

in order to:

 Assist planning for potential nonattainment

 Account for the very low ozone year of 2009

• Hypothetical 2012 design value is created by averaging 

the 4th highest ozone values over 2010 and 2011 only

• 2009 was dropped due to abnormally low ozone levels 

caused by: 

 Below normal temperatures at the surface

 Below normal temperatures aloft

 Above normal precipitation 

 A deep economic recession

• Justified by long-range weather forecasts for normal to 

above normal temperatures over much of the OTR
11

Hypothetical 2012 DV

2011 AQS data not yet certified

Unclassified/Attainment

EPA Proposed Nonatt.

> 75ppb outside of 

projected nonattainment 

areas

> 85ppb inside projected 

nonattainment areas

EPA Proposed Partial Nonatt.

Prelim DV > 75ppb
12

Analysis of 2011 Design Values

Data based on average 

of 2010 and 2011 4th

high ozone values 

Removing 2009 from 2011 Design Value

71 to 75 ppb

> 75 ppb
13

OTR Hypothetical 2012 DVs by MSA

Areas with hypothetical 2012 DV > 85ppb (moderate 

threshold) located within areas with potential 

marginal nonattainment (2010 DV)

New Haven-Milford

• 86ppb

New-York-Northern New Jersey-Long Island

• 87ppb, 87ppb, 86ppb, 86ppb

Philadelphia-Camden-Wilmington

• 89ppb, 88ppb, 86ppb, 86ppb

Washington-Arlington-Alexandria

• 88ppb, 87ppb, 86ppb 
14

OTR Hypothetical 2012 DVs by MSA

• Likely attainment/unclassified for 2010 DV

• 1 or more monitors with hypothetical 2012 DV > 

75ppb

Providence-New 

Bedford-Fall River, 

RI-MA

YoungstownWarrenBoardman, OH-PA

HarrisburgCarlisle, PA

York-Hanover, PA Indiana, PA (not in 

MSA)

Kent County, MD 

(not in MSA)

HagerstownMartinsburg, MDWV

Many areas 

outside the OTR
15

Screening Modeling Schedule

• Completed

Level 1 Screening 

(2007 Inventory & 2020 Control Scenario Using Proxies)

• Completed “Scenario 4”

• “Scenario 5” for Annual Meeting and potentially “Scenario 6”

Level 2 Screening 

(2007 Inventory & 2020 Control Scenario Using Proxies)

• For Fall 2012

Level 3 Screening 

(Complete 2020 Inventory + Boundary Conditions) 

• For SIP submission deadline TBD 

SIP Quality
16

Scenarios 5 and 6

Requested by Transport Assessment Group

• Scenario 5 is an OTW 2015 case

• Scenario 6 is an OTW 2018 case

 Emissions are extrapolated between already developed

 emission inventory years

CMAQ runs will look at inside and outside OTR 

factors by sector

 Both scenarios to be compared for 3 summer months.

 Scenario 5 will also be run for 7 months

CALGRID will be run with state-by-state factors by 

sectors on an episodic basis (about 40 days)
17

Upgrades from Level 2 to 3 Screening

• Upgraded Version 3 of Emission Inventory

 Decrease in NOXfor every state from 1-5%

 Decrease in VOC for every state except PA & DC

• 2020 Updates

 MOVES estimate

 Updated EGU proxy

• Emissions Outside of the OTR

 Full 2007 SESARM inventory

 2007 EGU/MOVES for LADCO

 Updated National Emissions Inventory for 

remaining areas/sectors

• Boundary Conditions

 Improved from static to modeled time variant
18

Plan B: 2020 EGU Proxy

• We will not be able to run ERTAC for outside of the 

OTR, and possibly not within, in time for Level 3 

Screening

• Improve the relative accuracy from a flat, across 

the board, 65% reduction

• Could be based on:

 Actual 2010 emission Levels

 CSAPR State Level Allocations

 CSPAR IPM Modeling Runs 

• Would be completed in under 2 months with a 

minimal level of resources 

• Need to determine who will conduct an analysis?
19

Level 3 Screening Schedule

•Version 3 of OTR+VA Inventory (w/ finalized MOVES)

•2020 MOVES estimate Early Spring •Updated National Emissions Inventory 2008

•ERTAC EGU code

•Other Regional Planning Orgs (including % reduction file) Late Spring •Category 3 Marine (Ocean going vessels)

•ERTAC EGU results

•Boundary Conditions Early Summer

•Start Modeling Runs

Mid Summer
20

Planned Level 3 Screening Activities

• Base Cases – 2007 and 2020

• Proposed Control Cases

 OTC “Controlled Inventory” – update Scenario 4

 Urban focused VOC Reduction

 Point/Nonroad/Area NOx Reduction

 Tier 3 + Low Sulfur Fuel 

 Theoretical CSAPR 2 Program
21

Other Committee Activities

• Model performance analyses on 2007 base

• Exploring BenMAP health benefit analysis

 Select modeling scenarios

 2010 rollback scenario to 75 ppb standard

• Analysis of transport patterns:

 Meteorological data

 Sensitivity modeling
22

Questions

• Committee Chair:

 Jeff Underhill (NH)

jeffrey.underhill@des.nh.gov (603) 271-1102

• Modeling Lead:

 Mike Ku (NY)

mku@dec.state.ny.us (518) 402-8402

• Emissions Inventory Lead:

 Susan Wierman (MARAMA)

swierman@marama.org (443) 901-1882

• OTC Committee Lead:

 Joseph Jakuta

jjakuta@otcair.org (202) 508-3839