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OAQPS Modeling, monitoring, emissions (AQAD) Updates
Rich Scheffe
US EPA – Office of Air Quality Planning and Standards
EGU
NonEGU
Nonpoint
Nonroad
Onroad
2005 Fires
Biogenic
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Example Benefits to EPA headquarters and the national air quality assessment community
• Treatment of fires in NEI and modeling inventories• VIEWS data analysis system
“the complex terrain, variety of emissions, meteorology and spatial vastness suggests that Western U.S. assessment practice will lead efforts in comprehensive air quality characterization out of necessity”
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Thanks• Kirk Baker• Tyler Fox• Lew Weinstock• Pat Dolwick• Joann Rice• Time Hanley• Robin Segall• Mark Houyoux• Ellen Baldridge• David Mintz• Jim Szykman (ORD)• Vasu Kilaru (ORD)• Jack Fishman (NASA)
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Topics
• Emissions and Modeling• National Monitoring Programs
– NAAQS driven• NO2 and ozone primary• NOx/SOx secondary• Ozone secondary
– Non regulatory• NCORE, CASTNET, CSN, satellites
• Blending data and Data integration/IT systems• National assessment tools and Western U.S. air
quality- reinforcing the importance of regional partnerships to address regional issues
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Primary Sources
HgHAPmetals
VOC (HAPs)
COSVOC
NO2
O3O3
hν
NO SO2
OH
H2SO4HNO3
NH3
OHHgo,Hg2
OH,O3
OH
OrganicPM
RO2
HO2
OH
hν
NitratePM
SulfatePM
ChemicalDeposition
gases
particles
Integration across pollutants, climate and media: tradeoffs and optimum strategies?
Climate forcing
Climate forcing
Climate forcing
Climate forcing
Climate forcing
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2050
20001970 1990 2010
Local/urbanRegionalHemispheric
Initial CAA BiogenicsRegional science
8-hr ozonePM2.5
(annual driver)
Regional Rules
New PMStandardsDaily/annual drivers
Climate-AQHemisphericalTransport
Evolutional change in National Air Pollution Management
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Emissions Measurements, National Emissions Inventory (NEI) and Modeled Emissions
• Note: new Emissions Inventory System (EIS) to house 2008 base NEI– Early 2011 availability
• 2001-2006 processed emissions for base year CMAQ simulations that drove CDC PHASE
• MP versions of 2002 and 2005 NEI and processed 12 km model fields (West and East)
• Note: EPA uses multi-year averaged fire emissions to carry to future projections
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Focus on improving Western U.S. oils and gas operations
• EPA Other Test Method 10 (OTM 10) – addressing fugitive VOCs– Open Path FTIR
• Broadband instrument (Multiple Compounds at once)• Monostatic (Source and Detector in one instrument)• Mounted on Orbital Scanner
• Summa Canisters– TO – 14A – GC/FID – TO – 15 – GC/MS
• Met Station• FLIR Camera
Robin R. SegallUS EPAOffice of Air Quality Planning and StandardsMeasurement Technology Group
WRAP Oil & Gas Workgroup October 20, 2009
Optical Remote Sensing (ORS)Path-Averaged Concentration Data
Nonlocalized Emission Source
Open Path FTIR
Retroreflector
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EGU
NonEGU
Nonpoint
Nonroad
Onroad
Biogenic
NorthEast
EGU
NonEGU
Nonpoint
Nonroad
Onroad
2005 FiresBiogenic
SouthEast
EGU
NonEGU
Nonpoint
Nonroad
Onroad
Biogenic
2005 Fires
MidWest
EGU
NonEGU
Nonpoint
Nonroad
Onroad
2005 Fires
Biogenic
SouthWest
EGU
NonEGU
Nonpoint
Nonroad
Onroad
2005 Fires
Biogenic
West
Nonpoint
Nonroad
OnroadNonEGU
EGU
Nonpoint
Onroad
EGUNonEGU2005 Fires
Nonpoint
2005 Fires
NonEGUOnroad
Nonpoint
Onroad
2005 Fires
NonEGU
EGU
Nonpoint
Onroad
NonEGU2005 Fires
NOx
NH3
Annual Average regional distribution of
NOx and NH3 Emissions (courtesy, M. Houyoux)
NOx
NH3
EGU NonEGU
Nonpoint
NonroadOnroad
2005 Fires
Western PM2.5
Nonpoint
Nonroad
Onroad
Biogenic
2005 Fires
NonEGU
VOC
Nonpoint
Nonroad
Onroad
Biogenic
NonEGU
2005 Fires
VOC
EGU
NonEGU
Nonpoint
Nonroad
Onroad
2005 Fires
Eastern PM2.5
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Air Quality Modeling
• Nationally– Variety of NAAQS REA and RIA, mobile source and point source
regulatory applications (2005 base): lifeblood of OAQPS• Constant evaluation (CMAQ) as new processes/versions are
developed by ORD
– Emerging developments• Treating fines scales to address MP issues and support
exposure modeling• Instrumented modeling (SA) to more efficiently address
attribution (primarily CAMX)• Climate-AQ interactions
– Searching for optimized AQ-climate benefits– Emphasis on short-lived species (O3, BC)
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Western U.S. Photochemical
Modeling Background(K. Baker)
• State of the science 3 dimensional photochemical grid models simulate the formation and transport of many secondarily formed pollutants and such as ozone and particulate matter
• Currently using both CMAQ v4.7 and CAMx v5.01
• Most recent modeling platform for western United States applications based on 2005 U.S. emissions; 2006 Canada and 1999 Mexico
• The 2005 emissions platform has been augmented with the WRAP Phase II oil and gas emission inventory
• Model performance for PM2.5 not ideal; sulfate ion estimates compare well to STN and IMPROVE but most other species do not
• Peak ozone tends to be underestimated in many urban areas; not currently capturing high winter ozone episodes
PM2.5 Sulfate Ion
PM2.5 Total Mass
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Western Transport Assessment (courtesy, K. Baker)
• Photochemical model source apportionment is a useful tool to assess interstate pollution transport
• Ozone and PM2.5 source apportionment used to track all anthropogenic emissions from western States to key receptor locations
• The sources selected for tracking with ozone source apportionment include all anthropogenic emissions from 17 selected States, Canada, Mexico, and boundary conditions
• Texas, Oklahoma, and Kansas are partial States due to domain configuration
• Annual 12 km source apportionment simulations for 2005 and 2006 tracking State specific anthropogenic emissions to ozone and PM2.5 estimated at key receptor locations
• Issues with PM2.5 model performance may delay PM2.5 transport assessment in the western U.S.
• Need to continue to work with WRAP and the western States to improve our western US modeling platform
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Modeling Issues (T. Fox)
1) tighter O3 stds in particular will place more of an emphasis on improving model performance in the non-California west--wintertime ozone formation issues, transport, visibility.
• Also will need to work closer with States that have not had to conduct such photochemical modeling for SIP demos for O3 or PM2.5
• We provide SIP modeling guidance and App W but what can we do to better inform and communicate to foster collaborations here?
2) Multiple players so how best to communicate and coordinate?
3) oil and gas development is key emissions source that we need to improve coordination on
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Ambient Air Monitoring
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Updating the Ozone Monitoring Network (L. Weinstock)
• Intent noted in 2008 NAAQS final rule; monitoring proposal published July 16, 2009, final rule expected in 2010
• Key provisions:– Additional monitors in smaller urban areas where not already
operating– New non-urban monitors (3 per state) to characterize sensitive
ecosystems and/or to provide coverage in less populated areas where elevated levels are occurring or likely
– Lengthened ozone monitoring seasons, where necessary, to ensure network operation when ambient levels approach NAAQS
• Proposed new monitors be deployed by January 1, 2012• Proposed ozone monitoring season changes effective on
the first day of ozone monitoring in 2011
Look for a final ozone monitoring rule sometime between April and August of 2010
162009 National Ambient Air Monitoring Conference, Nashville, TN
Revising the Ozone Monitoring Seasons
172009 National Ambient Air Monitoring Conference, Nashville, TN
Revising the Ozone Monitoring Seasons
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Nitrogen Dioxide
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Current NO2 (?) Monitoring Network
• The current network was implemented to support an annual standard
• The existing sites are satisfying multiple objectives including:– NAAQS compliance– assessment of ozone
formation and transport– health study support – Prevention of
Significant Deterioration (PSD)
The current NO2 network has approximately 400 sites, mostlyrepresenting area wide scales(neighborhood or larger scales)
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Near-road NO2 Site Selection
• Rank all road segments within a CBSA by Annual Average Daily Traffic (AADT) and then identifying a location or locations adjacent to those highest road segments where maximum hourly NO2 concentrations are expected to be highest
• Additional factors to consider: proximity to interchanges, fleet mix (diesel vs. light-duty), rapidly accelerating traffic, grade-climbing traffic, local terrain and meteorological effects
• Monitor probes must be no greater than 50 meters away, horizontally, from the outside nearest edge of the traffic lanes of the target road segment
• Located within 2 to 7 meters above the ground; may be placed on the interior side of any noise barriers (not ideal, however)
Beckerman et.al., 2008
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Proposed approach – Tier 1 – Near road sites
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Proposed approach – Tier 2 – area wide sites
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Alternative NO2 Network DesignArea-wide sites only
Note: Alaska would have 1 area-wide site in Anchorage and Hawaii would have 1 area-wide site in Honolulu. San Juan, PRwould have 2 area-wide sites.
Alternative approach – area wide (only) sites
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Role of National Assessment Tools in support of Western U.S. Air Quality
• Historical emphasis on Eastern US applications– Original RADM NAPAP modeling, ROM– The West is challenging relative to softer gradations in Eastern U.S.
topography
• Further confounded by:– Challenging emissions characterizations, e.g.,
• dominant role of fires• New dispersed oil/gas operations
– Meteorology• Precursor Concentration enhancing (mtn-valley inversions)• Exacerbated photochemical stimulation (bright surfaces/snow)
– Intercontinental transport
• Western Modeling Center?• Monitoring network design tethered to population surrogate approaches
– Natural conflict with Western heterogeneity
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Rethinking Nitrogen/ozone monitoring in rural/regional scales
• Nitrogen is universal across environmental issues/media, atmospheric chemistry and physics, and national control scenarios --echoing Paul T.
• Population weighted approach inadequate to characterize regional scale air quality – exacerbated in the West
• NAAQS by itself can not drive adequate network design
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National Nitrogen Observation NetworksAlso SEARCH, NPS
SLAMS
CASTNET
NADP
PM speciation NCORE
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Existing and proposed sentinel sites – LRTAP 2007 assessment
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What’s missing
• 1st…what is adequate (relative terms)– Great NO network– wet and dry nitrateBut,
• Rural coverage in general…especially Western States• Virtually no true NO2 observations• Skeleton NOy network• Missing routine and sustained vertical profile and aloft
data– Sentinel transport sites– Reliance on occasional intensive studies (2010 CALNEX)
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Rethinking Nitrogen/ozone monitoring in rural/regional scales
• Opportunities
– NAAQS• New NO2 standard
– Lead to molecule specific observations
• N/S secondary standards review– Possible growth of NOy observations– Increased attention to NH3– catalyze blending models and obs (spatial scarcity and wet-dry
anomolies)
• Tighter primary ozone standards & secondary ozone standard– Spread to regional/Western locations– Greater influence of hemispherical transport
– Collaborations across agencies, remote sensing
– Blending models and observations
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Satellites provide best source of ambient NO2: Accountability and Trends
Figure 20. Left - superimposed Eastern U.S. emission and combined GOME and SCIAMACHY NO2 1997-2002 trends (Kim et al., 2006); right - GOME NO2 trends from 1995 – 2002 (after Richter, 2005). Clear evidence of reductions in midwest U.S. and European NOx emissions, and increased NOx generated in Eastern Asia.
Figure 21. 2004 OMI NO2 column images aggregated for all Fridays (left) and Sundays (right) indicating weekend/weekday patterns associated with reduced Sunday emissions (source, Husar).
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Tropospheric NO2 columns retrieved from the SCIAMACHY satellite instrument for 2004 –2005 (after Martin et al., 2002)
Global Distribution of Nitrogen Dioxide: Precursors to Ozone Formation (Fishman)
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• Understanding the the Oxidizing Capacity (amount and distribution of OH) of the Troposphere and the Tropospheric Ozone Cycle Drives the Science
• Species in Red Can be Observed by Satellite
OH
Overview of the GEO-CAPE MissionGeostationary Coastal and Air Pollution Events
Mission
Jack FishmanScience Directorate
NASA Langley Research Center
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TOMS (Daily) 100-km res.
Geostationary (Hourly)
OMI (Daily)
Map of Houston and surrounding area
Best Method to Observe Pollution is from Geostationary Orbit
Technology Readily Available:
O3, CO, NO2, SO2, CH2O and aerosols
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0
5
10
15
20
25
30
35
40
45
0 3 6 9 12 15 18 21 0 3 6 9 12 15 18 21 0
0
5
10
15
20
25
30
35
40
45
0 3 6 9 12 15 18 21 0 3 6 9 12 15 18 21 0
Integrated Column NO2 Accurately Captures Diurnal Behavior
Sur
face
NO
2 C
alcu
late
d b
y C
MA
Q
(pp
b)
Col
umn
NO
2 C
alcu
late
d b
y C
MA
Q
(101
5 m
ol.
cm-2)
0
5
10
15
20
25
30
35
40
45
0 3 6 9 12 15 18 21 0 3 6 9 12 15 18 21 0
Surface NO2 Column NO2
Surface NO2 Concentrations Calculated by CMAQ Plotted as a Function of Hour: June 22-23, 2005
Surface Concentrations and Integrated NO2 Column Calculated by CMAQ Plotted as a Function of Hour: June 22-23, 2005
Measurements from GeoTRACE Capture Daylight Portion of Diurnal Cycle
Observations from GEO: NO2 Measurements Every 30-60 Minutes Throughout Sunlit Hours
June 22 Hour of Day (GMT) June 23
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2001 4th High Observed Concentrations(at 436 test sites used in the interpolations)
2001 4th High CMAQ Concentrations(for each grid cell)
2001 VNA 4th High Concentrations(4th High Interpolation Only)
2001 eVNA 4th High Concentrations(4th High Interpolation Only)
2001 VNA 4th High Concentrations(Daily Interpolations)
2001 eVNA 4th High Concentrations(Daily Interpolations)
2001 VNA 4th High Concentrations(4th High Interpolation Only)
2001 eVNA 4th High Concentrations(4th High Interpolation Only)
2001 VNA 4th High Concentrations(Daily Interpolations)
2001 eVNA 4th High Concentrations(Daily Interpolations)
2001 VNA 4th High Concentrations(4th High Interpolation Only)
2001 eVNA 4th High Concentrations(4th High Interpolation Only)
2001 VNA 4th High Concentrations(Daily Interpolations)
2001 eVNA 4th High Concentrations(Daily Interpolations)
2001 VNA 4th High Concentrations(4th High Interpolation Only)
2001 eVNA 4th High Concentrations(4th High Interpolation Only)
2001 VNA 4th High Concentrations(Daily Interpolations)
2001 eVNA 4th High Concentrations(Daily Interpolations)
=
Blending observations and models: Data Fusion (Rizzo/Baldridge)-Support for poorly monitored areas
e.g., Rural ozone characterization
Another Eastern U.S. HQ bias?
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2001-2006 CDC PHASE ozone and PM2.5 surfaces (Kilaru)
http://www.epa.gov/nerlesd1/land-sci/lcb/lcb_sads.html
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Data/IT systems
• A word about VIEWS/TSS
• Collaboration with NASA ROSES CSU/CMAS, USDA and Bluesky Rains, GEOSS
• Community cost sharing
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• Integration of systems to improve – air quality models
for forecast– Current and– Retrospective
assessments
• Global-Regional Air Quality Connections
• Climate-AQ connections
Maximizing space/time/composition through systems integration
Land AQ Monitors
Total column depth(through Satellites)
AQ model results
Vertical Profiles
Integrated Observation- Modeling
Optimized air chemistry
Characterizations
Exposure/Health
Air managem
entecosystem
s
accountability
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Appendices
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Near-road NO2 Site Selection
• Rank all road segments within a CBSA by Annual Average Daily Traffic (AADT) and then identifying a location or locations adjacent to those highest road segments where maximum hourly NO2 concentrations are expected to be highest
• Additional factors to consider: proximity to interchanges, fleet mix (diesel vs. light-duty), rapidly accelerating traffic, grade-climbing traffic, local terrain and meteorological effects
• Monitor probes must be no greater than 50 meters away, horizontally, from the outside nearest edge of the traffic lanes of the target road segment
• Located within 2 to 7 meters above the ground; may be placed on the interior side of any noise barriers (not ideal, however)
Beckerman et.al., 2008
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Overview of Public Comments on NO2• Current Standard
– CASAC, environmental/public health groups, and most states agree with the proposed conclusion that the current standard alone is not requisite to protect public health with an adequate margin of safety
– Some industry groups commented that revision of the current standard is not justified at this time based largely on uncertainties in the scientific evidence
• Approach to setting a new 1-hour standard and establishing a 2-tiered monitoring network
– CASAC, environmental/public health groups, and most states support the establishment of a new 1-hour standard and the need to obtain better information on NO2 concentrations around roads
• Groups disagree regarding the most appropriate approach– Industry does not support the establishment of a new 1-hour standard or the proposed
monitoring network based largely on uncertainties in the scientific evidence
• Standard level and form – CASAC and some States support our proposed ranges of levels and recommend a
98th percentile form under the proposed approach – Environmental/public health groups recommend a lower level with a more stringent
form (e.g., 99th percentile or no exceedance) – Industry groups recommend a higher level and generally recommend a 98th percentile
form
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CASAC Comments on NO2 Approach• CASAC strongly supports the establishment of a new 1-hour
standard and the need to obtain better information on NO2 concentrations around roads
• CASAC consensus was that we need to monitor near roads, but CASAC members were split regarding the most appropriate approach
• The majority of CASAC members favor the proposed approach noting that this approach would be more effective than the alternative at limiting roadway-associated exposures
• A minority of CASAC members favor the alternative approach, combined with the establishment of a research-oriented near-road network noting…– That epidemiologic studies did not use near-roadway exposure data – The limited information available at this time to inform the design of a
national roadside monitoring network
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Other Public Comments on NO2
• Most environmental and public health organizations strongly support the proposed NAAQS and near-road monitoring
• Mixed response from State, Local, and tribal air monitoring groups and agencies.– Mostly support near-road monitoring, but are divided
on:• 1) Specifics on monitor requirement triggers and siting, and• 2) Whether EPA should run a research network (non-
regulatory) or an actual regulatory network
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Anticipated NO2 Implementation Schedule
MilestoneDates for Proposed
ApproachDates for Alternative Approach
State Designation
Recommendations to EPA
January 2011: Based on existing network data because near-road monitors not in place
January 2011 utilizing existing network
Designations
January 2012: EPA designates all/most areas as “unclassifiable” because near road monitors not in place
January 2012 utilizing existing network
New NO2 Monitoring Network
January 1, 2013: Monitoring sites operational
January 1, 2013: New area-wide monitoring sites operational but not utilized for current round of designations
Nonattainment Re-Designations
January 2018 based on 2013 – 2016 ambient data
Not Applicable
Attainment DateJanuary 2023: 5 years after date of re-designations
January 2017
Under a judicial consent decree, EPA must complete this review of the primary NO2
standard by January 22, 2010.
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County-Level Ozone Design Value Maps based on 2006-2008 data
9/8/09Contact David Mintz x5224 with questions
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Counties with 2006-2008 8-hour Ozone Design Value Above 0.075 ppm
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 8-hour Design Value Above 0.075 ppm
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Counties with 2006-2008 8-hour Ozone Design Value Above 0.070 ppm
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 8-hour Design Value Above 0.070 ppm
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Counties with 2006-2008 8-hour Ozone Design Value Above 0.065 ppm
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 8-hour Design Value Above 0.065 ppm
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Counties with 2006-2008 8-hour Ozone Design Value Above 0.060 ppm
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 8-hour Design Value Above 0.060 ppm
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Counties with 2006-2008 W126 Ozone Design Value Above 21
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 W126 Value Above 21 ppm-hours
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Counties with 2006-2008 W126 Ozone Design Value Above 15
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 W126 Value Above 15 ppm-hours
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ounties with 2006-2008 W126 Ozone Design Value Above 7
Alaska
Hawaii Puerto Rico
Virgin Islands
Counties with 2006-2008 W126 Value Above 7 ppm-hours
53Monitoring site locations for CAMX Hiawatha EIS project, courtesy ENVIRON
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Additional counties that would be nonattainment for a W126 secondary standard compared to alternative primary standards
(based on 2006-2008 data)
7 ppm-hours 15 ppm-hours
21 ppm-hours
0.060 ppm 29 5 1
0.065 ppm 34 5 1
0.070 ppm 84 10 1
0.075 ppm 243 29 3
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Western U.S. Photochemical Modeling Background
• State of the science 3 dimensional photochemical grid models simulate the formation and transport of many secondarily formed pollutants and such as ozone and particulate matter
• Currently using both CMAQ v4.7 and CAMx v5.01
• Most recent modeling platform for western United States applications based on 2005 U.S. emissions; 2006 Canada and 1999 Mexico
• The 2005 emissions platform has been augmented with the WRAP Phase II oil and gas emission inventory
• Model performance for PM2.5 not ideal; sulfate ion estimates compare well to STN and IMPROVE but most other species do not
• Peak ozone tends to be underestimated in many urban areas; not currently capturing high winter ozone episodes
PM2.5 Sulfate Ion
PM2.5 Total Mass
56
Ozone Designations
• Photochemical model source apportionment tracks the formation and transport of ozone and PM2.5 from specific emissions sources and allows the calculation of contribution to specific receptors
• Photochemical model source apportionment is an ideal tool to estimate the combined impact of multiple factors of the 9 factor ozone designation analysis
• Source apportionment photochemical modeling for ozone designations tracks all anthropogenic NOX and VOC emissions from specific counties for contribution to ozone estimated at nonattainment monitor locations (does not include fires for contribution analysis)
• Annual 2005 and 2006 source apportionment modeling for Western U.S. at 12 km grid resolution
• Counties were selected if they comprised part of a CSA or CBSA that had a violating monitor for the new 8-hr ozone NAAQS; EPA Regional offices added additional counties for tracking in the model
Model tends to underestimate the higher ozone concentrations (ozone observation/10 on X axis)
57
NADP sites: approximately 250 – weekly precipitation samplesanalyzed for sulfate, SO4
-2, nitrate, NO-13, and ammonium, NH+1
4
active
inactive
58
Castnet sites: ~ 86; weekly averaged dry gases - SO2, HNO3, particles- NH4, SO4, NO3.
59
Ozone and Climate (P. Dolwick)
• In addition to posing a significant risk to public health and welfare, ozone is important as a “short-lived” climate forcer.
• contribution is ~20% that of CO2
• ozone reductions would yield immediate climate benefits
• Climate-focused ozone reductions may involve different pollutants and sectors than strategies designed to lower short-term peaks
• e.g., methane and carbon monoxide
• EPA is building modeling capacity to assess joint climate/health impacts of ozone precursor reductions. (Adapted from IPCC Synthesis Report, 2007;
as well as Ramanathan and Carmichael, 2008)
60
Ozone Monitor LocationsMetropolitan Statistical Areas
Red Outlines – No Ozone Monitors(based on complete data for
2004-2006 and 2005-2007)
MSA of population 50k – 350k with no current ozone monitors
61
Summary of the NO2 NAAQS and Monitoring Proposal
• Proposed approach – Retain the current annual standard and to increase public health
protection against respiratory effects linked to short-term NO2 exposure by setting a new 1-hour standard reflecting the maximum allowable NO2 concentration anywhere in an area
• Level: Proposed 80 to 100 ppb and solicited comment from 65 to 150 ppb
• Form: proposed 99th percentile and solicited comment on 98th percentile
– In order to have monitors in locations where peak NO2 concentrations are likely to occur, we also proposed to require a 2-tiered NO2 monitoring network that would include…
• Near road monitors: Monitors placed within 50 meters of major roadways, and
• Area-wide monitors: Monitors placed away from major roadways to measure NO2 concentrations that occur more broadly across the community
62
• Alternative approach– We solicited comment on setting the 1-hour standard
such that it would reflect the allowable area-wide NO2 concentrations
– Under this alternative, we solicited comment on standard levels from 50 to 75 ppb
– In order to have monitors that measure area-wide NO2 concentrations, we solicited comment on requirements for monitor placement, including a requirement that monitors be located at some minimum distance from major roadways
Summary of the NO2 NAAQS and Monitoring Proposal
63
PM10-2.5 Speciation Monitoring Pilot (J. Rice)
PM10-2.5 mass monitoring required as part of NCore
• Some measurement issues not yet resolved
• Prior to future implementation, a small pilot project will occur in 2010 at two locations– Primarily using PM10-2.5 FRMs and dichot FEMs
– Goal to identify key target species
– Further development of analysis methods
– Develop Standard Operating Procedures (SOPs)
• CASAC consultation on pilot February 2009– Supported pilot monitoring effort
– Strongly recommended use of dichot samplers
– Recommended analysis of pilot data prior to network deployment…”move slowly”
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Significant Temporal Correlation Between In Situ and OMI-derived Surface NO2
Correlation of Coincident Observations over 2005
Lamsal et al., JGR, 2008
Future work NO2: (led by Martin and Lamsal)
Extend to operational with OMI and GOME-2 using monthly GEOS-Chem NO2 profiles
• Continue developing relationship between column and surface NO2 (lightning, clouds, spatial resolution)
• Evaluation againstsurface NO2 measurementsSEARCH Network (Photolytic converter analyzers ), SLAMS/EPA Network (Molybdenum converter analyzers), and Langley/VADEQ/EPA and EPA-RTP sites (Photolytic converter analyzer)
Satellite NO2 Portion of AIRNow Satellite Data Processor (ASDP) 2009 NASA ROSES Project (P. Dickerson –PI, courtesy Szykman)..
Significant Temporal Correlation Between In Situ and OMI-derived Surface NO2