Transcript Further Development and Application of the CMAQ Ozone and Particle Precursor Tagging Methodologies (OPTM & PPTM) 7th Annual CMAS Conference Chapel Hill, NC 6-8 October 2008 Presented.

Further Development and Application
of the CMAQ Ozone and Particle
Precursor Tagging Methodologies
(OPTM & PPTM)
7th Annual CMAS Conference
Chapel Hill, NC
6-8 October 2008
Presented by Sharon Douglas
ICF International, San Rafael, CA
Co-Authors:
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Tom Myers
Yihua Wei
Jay Haney
Tom Braverman,
ICF
EPA OAQPS
Presentation Outline
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Overview of CMAQ/OPTM & PPTM source attribution methods
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Application of CMAQ/OPTM & CMAQ/PPTM to support ozone &
PM2.5 designations (example for Milwaukee)
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Application of CMAQ/PPTM to characterize CAAA-related reductions in
PM2.5 for cost/benefit analysis
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Next steps
OPTM & PPTM: General Concepts
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Emissions (or IC/BC) species are tagged in the input files and continuously
tracked throughout the simulation
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Tags can be applied to source regions, source categories, individual sources,
and/or IC/BCs
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Tagged species have the same properties and are subjected to the same
processes (e.g., advection, chemical transformation, deposition) as the actual
species
OPTM & PPTM: General Concepts
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OPTM species include ozone, NOx & VOC
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PPTM species include PM-related S, N, SOA, POC, EC & other inorganic
particulates*
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Base simulation results not affected by tagging
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OPTM & PPTM quantify the contribution of tagged sources to simulated
species concentrations & deposition
*PPTM has also been implemented for mercury
Implementation of OPTM for CMAQ
(Overview(1))
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Total emissions of both NOx and VOC from the desired sources or
source categories are tagged (e.g., NOx_t1, NOx_t2, VOC_t1, VOC_t2)
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Oxidant tracers (OXN_t1, OXV_t1, OXN_t2, OXV_t2) correspond to
the oxidant produced from NOx & VOC for each tagged category
Implementation of OPTM for CMAQ
(Overview(2))
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Advection/Diffusion:
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Gas Phase Chemistry:
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Use standard CMAQ algorithms
Chemistry step called as usual
Changes in NOx, VOC & oxidant (ΔVOC, ΔNOX & ΔOX) are calculated and
apportioned to tags
Deposition:
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Calculated for the tags based on fractional change in total NOx, VOC & oxidant
due to deposition
Implementation of PPTM for CMAQ (Overview)
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Within CMAQ, tagging is accomplished by adding duplicate species (e.g.,
ANO3_t1, ANO3_t2)
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More than 50 (gas & aerosol phase) species per tag required to track total
PM2.5 (e.g., for nitrogen: ANH4I, ANH4J, ANO3I, ANO3J, NO, NO2,
NO3, N2O5 …)
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Key considerations/assumptions:
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Linear processes simulated directly
Potentially non-linear processes calculated for total species and apportioned to tags
PPTM can also be used to estimate contributions to N and other forms of
deposition
Application of CMAQ/OPTM & PPTM for the
Milwaukee Area
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Objective: To identify the source regions that potentially contribute to high
ozone and high PM2.5 concentrations in the Milwaukee, WI area
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Specs:
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Regional-scale modeling domain
2002 base year; limited simulation periods (1 month
for ozone; 4 months for PM2.5)
13 tagged source regions (county level)
Application of CMAQ/OPTM & PPTM for the
Milwaukee Area: Domain
12-km resolution
Application of CMAQ/OPTM & PPTM for the
Milwaukee Area: Tags
T1: Milwaukee Co., WI
T2: Washington Co., WI
T3: Ozaukee Co., WI
T4: Waukesha Co., WI
T5: Racine Co., WI
T6: Sheboygan & Fond du Lac Co., WI
T7: Dodge, Jefferson & Walworth Co., WI
T8: Kenosha Co., WI
T9: Cook Co., IL
T10: Lake, McHenry, Kane, Dupage Co.,IL
T11: Will Co., IL & Lake & Porter Co., IN
T12: Remainder of 12-km grid
T13: IC/BCs
CMAQ/OPTM Results for the Milwaukee Area: NOx
Average Contribution to Maximum 8-Hour Ozone
Tag 1: Milwaukee Co.
Tag 9: Cook Co.
Tag 10: 4 Other IL Co.
CMAQ/OPTM Results for the Milwaukee Area:
VOC
Average Contribution to Maximum 8-Hour Ozone
Tag 1: Milwaukee Co.
Tag 9: Cook Co.
Tag 10: 4 Other IL Co.
CMAQ/OPTM Results for a Monitoring Site: NOx
& VOC
Average Contribution to Maximum 8-Hour Ozone
CMAQ/OPTM Contributions to 8-Hr Ozone for Milwaukee: NOx & VOC
100
ppb
80
60
IC/BCs
Milwaukee Co.
12-km grid
40
20
0
T1
T2
T3
T4
T5
T6
T7
NOx
T8
VOC
Milwaukee Bayside
T9
T10
T11
T12
T13
Total
Summary CMAQ/OPTM Results for All Monitoring
Sites: NOx & VOC
Summary of CMAQ/OPTM NOx Contributions to 8-Hr Ozone for Milwaukee: High Ozone Days
50
ppb
40
30
20
10
0
KPP
MCHC
MDNR
MUWM
MBYS
OGFT
OHBP
RAPC
WSLG
WCLV
Summary
CMAQ/OPTM
Contributions
Ozone forRemainder
Milwaukee:
Milwaukee
Co. of
Other
Tagged WI VOC
Counties
Tagged ILto&8-Hr
IN Counties
of High
12-kmOzone
Grid Days
IC/BCs
50
ppb
40
30
20
10
0
KPP
MCHC
Milwaukee Co.
MDNR
MUWM
Other Tagged WI Counties
MBYS
OGFT
Tagged IL & IN Counties
OHBP
RAPC
Remainder of 12-km Grid
WSLG
IC/BCs
WCLV
CMAQ/PPTM Results for a Monitoring Site
CMAQ/PPTM Source Region & Species Contributions to Avg PM2.5 for Milwaukee
8
12-km grid
ug/m3
6
IC/BCs
Milwaukee Co.
4
2
0
T1
T2
T3
SO4
T4
NO3
T5
NH4
T6
T7
T8
T9
POA
PEC
Other Primary PM2.5
Milwaukee Virginia Fire Station
T10
T11
T12
T13
CMAQ/PPTM Results for a Monitoring Site
CMAQ/PPTM Source Region & Species Contributions to Avg PM2.5 for Milwaukee
8
12-km grid
ug/m3
6
4
IC/BCs
Waukesha Co.
Milwaukee Co.
2
0
T1
T2
T3
SO4
T4
NO3
T5
NH4
T6
T7
T8
POA
PEC
Other Primary PM2.5
Waukesha
T9
T10
T11
T12
T13
Summary CMAQ/PPTM Results for All Monitoring Sites
8
Summary of CMAQ/PPTM Source Region Contributions to Avg PM2.5 for Milwaukee
ug/m3
6
4
2
0
DNR
Milwaukee Co.
FDH
CHC
Other Tagged WI Counties
FAA
VFS
Tagged IL & IN Counties
OZK
Remainder of 12-km Grid
WKS
IC/BCs
Summary for Milwaukee
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OPTM & PPTM can be used to quantify
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the contribution of emissions (by species) from specified source regions to CMAQderived concentrations
the potential for sources/source regions to contribute to nonattainment in a given
area
Contributions vary by location and are different for
the different species (NOx, VOC and PM species)
Ozone & PM2.5 nonattainment issues in the
Milwaukee area are the combined result of local
emissions as well as intra- & inter-state transport
§812 Cost/Benefit Analysis: PM2.5 Modeling Component
CMAQ-Ready 36-km
Emission Inventories
(US Domain)
1990
2000 without CAAA
2000 with CAAA
2010 without CAAA
2010 with CAAA
2020 without CAAA
2020 with CAAA
2002 Meteorological Inputs
CMAQ Model
(Version 4.6)
Annual Simulation
Period
Annual PM2.5, Visibility
& Deposition
(US Domain)
1990
2000 without CAAA
2000 with CAAA
2010 without CAAA
2010 with CAAA
2020 without CAAA
2020 with CAAA
Geophysical & IC/BC Inputs
Health and Ecological Assessments
Application of CMAQ/PPTM to Support the §812
Cost/Benefit Analysis
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Objectives:
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Quality assurance
To quantify and compare the source category contributions to PM2.5 both with
and without the Clean Air Act Amendments (CAAA)
Specs:
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National-scale modeling domain
Annual simulation period; two scenarios (2010 without
CAAA and 2010 with CAAA)
7 tagged source categories
Application of CMAQ/PPTM for the §812 Modeling
Analysis: Domains
36-km resolution
for PM2.5
WUS
EUS
CONUS
Application of CMAQ/PPTM for the §812
Modeling Analysis: Tags
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T1: EGU sources (U.S.)
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T2: Non-EGU point sources (U.S.)
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T3: On-road mobile sources (U.S.)
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T4: Non-road mobile sources (U.S.)
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T5: Area (non-point, non-mobile) sources (U.S.)
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T6: Initial and boundary conditions (IC/BCs)
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T7: All other sources (natural emissions,
offshore sources, and non-U.S. sources)
CMAQ/PPTM Results: Contribution from EGU Sources
(Tag 1)
Annual Average PM2.5
2010 without CAAA
2010 with CAAA
CMAQ/PPTM Results: Contribution from Non-EGU Point
Sources (Tag 2)
Annual Average PM2.5
2010 without CAAA
2010 with CAAA
CMAQ/PPTM Results: Contribution from On-Road
Sources (Tag 3)
Annual Average PM2.5
2010 without CAAA
2010 with CAAA
CMAQ/PPTM Results for a Monitoring Site
Annual Average PM2.5
50
ug/m3
40
30
20
10
0
EGU
Non-EGU
On-road
mobile
Non-road
mobile
NoCAAA
Area
CAAA
Philadelphia
IC/BCs
Other
Total
Summary of PPTM Results for the §812 Modeling
Analysis
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PPTM used as a probing tool to attribute the overall reductions in
PM2.5 (due to the CAAA measures) to specific source categories
Total simulated PM2.5 concentration is lower
under the CAAA scenario, primarily due to
reductions in area- & point-source (EGU &
non-EGU) emissions (relative importance
varies by region and by location)
Health benefits can be similarly attributed to
source categories, sources, or specific
measures
Next Steps
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Incorporate OPTM & PPTM (for ozone and PM2.5) into CMAQv4.7
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Incorporate PPTM (for mercury and 10 additional toxic pollutants)
into CMAQv4.7
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Distribute OPTM & PPTM codes through CMAS