Crawford SARP

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    NASAs Research ProgramNASAs Research Program

    in Tropospheric Chemistry:in Tropospheric Chemistry:

    How are Human InfluencesHow are Human Influences

    Changing EarthsChanging EarthsAtmosphere?Atmosphere?

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    Emission Transformation/Oxidation Removal(NOx, CO, Hydrocarbons) (O3, OH, CH2O, HO2, RO2) (HNO3, H2O2, ROOH)

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    Global NOx Sources

    (teragrams of nitrogen per year)

    Source Magnitude (uncertainty)

    Fossil Fuels 22 (13-31)

    Biomass Burning 8 (3-15)

    Soil Emissions 7 (4-12)

    Aircraft 0.85 (0.5-1)

    Lightning 5 (2-20)

    Global Hydrocarbon Sources

    (teragrams of carbon per year)

    Source Possible Range

    Fossil Fuels 46-95

    Biomass Burning 25-80

    Emission from Foliage 800-1500

    Soils/Oceans/Grasslands 15-30

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    Emission Transformation/Oxidation Removal(NOx, CO, Hydrocarbons) (O3, OH, CH2O, HO2, RO2) (HNO3, H2O2, ROOH)

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    Tropospheric Ozone Significance:

    Environmentally Important: Ozone is a pollutant

    adversely impacting health and agriculture

    Chemically Important: Ozone initiates the

    oxidation cycles responsible for removing most

    polluting gases from the atmosphere. Theseoxidation cycles also influence ozone itself.

    Climatically Important: Ozone influences climate

    directly as a greenhouse gas and is mostimportant in the upper troposphere where

    temperatures are cold. Ozone exerts an indirect

    influence through the oxidation of other

    greenhouse gases.

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    HNO3

    X

    XOHCl

    NH2

    NO

    H2SO4

    HSO3

    SO2

    CO

    H2O

    HO2

    HH2O2

    O3O(1D)

    O(3P)

    HO2

    NO

    H2

    Multi-stepprocess

    O3

    CH3CCl3

    HXNO2

    N2,O2O2

    hv

    H2O CXHY

    CO

    hv

    Removal byprecipitation

    O2

    SO2

    NH3

    Multi-stepprocess

    Multi-stepprocess

    Multi-stepprocess

    Removal byprecipitation

    Multi-stepprocess

    Removal byprecipitation Removal by pre-

    existing

    particles or

    nucleation

    OHCH3SCH3

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    Emission Transformation/Oxidation Removal(NOx, CO, Hydrocarbons) (O3, OH, CH2O, HO2, RO2) (HNO3, H2O2, ROOH)

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    Satellites: mainly column amountsSatellites: mainly column amountsOO33, CO, NO, CO, NO22, HCHO, HCHO Aerosol optical depth, propertiesAerosol optical depth, properties

    Aircraft: DC-8, P-3B, B200Aircraft: DC-8, P-3B, B200Comprehensive in situ chemical and aerosolComprehensive in situ chemical and aerosol

    measurementsmeasurements

    Lidar remote sensing of ozone, water vaporLidar remote sensing of ozone, water vapor

    and aerosol optical propertiesand aerosol optical properties

    Solar radiation measurementsSolar radiation measurements

    Global and Regional ModelsGlobal and Regional Models

    Source-receptor relationships for pollutionSource-receptor relationships for pollution

    Inverse modeling for estimating emissionsInverse modeling for estimating emissions

    Aerosol radiative forcingAerosol radiative forcing

    Detailed chemical processingDetailed chemical processing

    Model error characterizationModel error characterization

    Data assimilationData assimilationDiagnostic studiesDiagnostic studies

    Calibration and ValidationCalibration and Validation

    Retrieval developmentRetrieval development

    Correlative informationCorrelative informationSmall scale structure and processesSmall scale structure and processes

    Airborne Field Campaign Strategy: Maximize the value of satelliteAirborne Field Campaign Strategy: Maximize the value of satellite

    data for improving models of atmospheric composition and climatedata for improving models of atmospheric composition and climate

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    Ozone (O3): Aura-MLS, Aura-TES

    Carbon Monoxide (CO): Terra-MOPITT, Aqua-AIRS, Aura-TES

    Nitrogen Dioxide (NO2): Aura-OMI

    Formaldehyde (CH2O): Aura-OMI

    Aerosols: Terra-MODIS and MISR, Aqua-MODIS, CALIPSO, Glory-APS,

    Aura-OMI

    NASA satellite observations of Atmospheric Composition

    Terra

    10:30

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    OMI & MLS produce aOMI & MLS produce a

    tropospheric ozonetropospheric ozoneproduct by subtractingproduct by subtracting

    the MLS stratosphericthe MLS stratospheric

    ozone from OMIozone from OMI

    column ozone.column ozone.

    This can be comparedThis can be compared

    to the more sparse butto the more sparse but

    direct observationsdirect observations

    from TESfrom TES

    OMI & MLS: Global Tropospheric Ozone Residual

    Mark Schoeberl, NASA GSFC*Notice that largest ozone enhancements are downwind of source regions

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    CO observations from MOPITT and AIRS: Tracing

    pollution transport from combustion sources

    Strengths:

    -Atmospheric lifetime of ~2 months is ideal for observing

    long-range transport which takes place in mid-troposphere.

    -Excellent detection of enhanced CO from fires

    -4.2m thermal emission allows detection both day and nightLimitations:

    -Sensitivity limited mainly to middle troposphere

    -No significant vertical resolution

    Future observations aim to provide additional

    detection for 2.3 m channelStrengths:

    -Solar reflection at 2.3 m will be sensitive to total columnextending down to the surface

    -Information on surface concentrations may be derived in

    combination with

    4.6m observations

    Limitations:-Solar reflection limits

    detection to daytime

    mainly over land

    20

    10

    0

    Altitude(km)

    250200150100500

    CO, ppb

    4.6m

    Avg. Kernel

    2.3m

    Avg. Kernel

    Avg. CO

    profile Los

    Angeles (July

    2004)

    MOPITT Seasonal Average CO (850mb)

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    Strengths:

    -Atmospheric NO2 abundance is weighted toward surface,

    therefore column measurement can yield useful information onvariability in surface emissions

    -Atmospheric lifetime of NO2 is less than one day near the

    surface, therefore observed enhancements are in close proximity

    to sources.

    Limitations:

    -Stratospheric abundance of NO2 must be subtracted to give a

    tropospheric residual (similar to ozone), however, troposphericNO2 dominates the column in polluted areas.

    -Partitioning between NO2 and NO must be assessed to estimate

    total NOx, although NO2 typically constitutes ~80% of near-

    surface NOx

    -Emission of NOx undergoes large diurnal variability

    NO2 observations from OMI: High

    resolution information on anthropogenic

    emissions

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    OMI NO2: Beijing Olympics

    Br an Duncan, NASA GSFC

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    A 50% reduction

    in NO2!

    A 20-40%

    reduction in SO2!

    Beijing Olympics:

    Pollution Reduction Efforts

    OMI Tropospheric NO2 around Beijing, China

    x1015m

    olec/cm2

    Month

    Bryan Duncan, NASA GSFC

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    Formaldehyde observations from OMI: Oxidation of biogenic and

    other hydrocarbon emissions

    Strengths:

    -Atmospheric CH2O abundance is weighted

    toward surface with no significant stratospheric

    burden-Oxidation of most hydrocarbons result in CH2O,

    therefore it is an excellent proxy for the

    integrated influence of hydrocarbons on ozone

    photochemistry

    Limitations:

    -CH2O is not directly emitted, but rather is abyproduct of photochemistry. With a short

    lifetime (hours), it undergoes large changes

    throughout the day.

    -Atmospheric lifetime of CH2O is less than one

    day, observed enhancements occur at variable

    distances from hydrocarbon sources, depending

    on their atmospheric lifetime.

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    NASA Tropospheric Chemistry Field Campaigns (1983-2008)

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    INTEX B Fli ht P id S i F d V lid ti

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    INTEX-B Flights Provide Science-Focused Validation

    Opportunities: DC-8 Flight 16 from Anchorage

    MLS

    TES-LAsian pollution

    Large concentrations of ozone

    in the Pacific troposphere

    Multiple satellite tracks

    are examined for validation

    DIAL O3 (E. Browell, NASA LaRC)

    CO prediction from the RAQMS

    model (R. B. Pierce, NASA LaRC)

    0

    2

    4

    6

    8

    10

    12

    Altitude(km)

    0

    50

    100

    150

    200

    250

    300

    CO(ppbv)

    DACOM CO (G. Sachse and G. Diskin, NASA LaRC)

    Large concentrations of ozone are associated

    with high CO suggesting Asian pollution

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    OMI NO Tropospheric Column Compared with GEOS Chem

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    OMI NO2 Tropospheric Column Compared with GEOS-Chem

    Asian NOx anthropogenic

    emissions for the year 2000

    2 x 2000 Asian NOx

    emissions

    OMI NO2 tropospheric column observations suggest a factor of 2 increase of

    Asian anthropogenic NOx emissions from 2000 to 2006.

    D. Jacob, Harvard

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    Satellite observations reveal

    increasing Asian NO2 emissions

    Transport of Asian Ozone and its Precursors

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    The mean Asian ozone, CO, NOx, and PAN enhancements at 800 hPa for INTEX-B

    Latitudinal distribution of NO2 and PAN at 1.5 -5 km

    Transport of Asian Ozone and its Precursors

    Ozone CO

    NOx PAN

    NO2 PAN

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    HOW DO AIRBORNE FIELD CAMPAIGNS AFFECT POLICY?HOW DO AIRBORNE FIELD CAMPAIGNS AFFECT POLICY?

    Information synthesis

    Improved knowledge;publications in scientific journals

    Summary assessments for policymakers:Intergovernmental Panel on Climate ChangeArctic Council

    UNEP Hemispheric Transport of Pollution Assessment

    Better-informed decisions to protect the environment

    Satellites

    Models Aircraft

    Improved model predictions

    2 yrs

    5 yrs

    10 yrs

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    Contrasting Conditions

    along a Frontal Zone

    P-3B Flight 19

    100 150 200 250 300 350 400 450 500 550 600CO (ppbv)

    0

    1

    2

    3

    4

    5

    Altitude

    (km)

    10 10

    DC-8 DC-8

    Cl d bi

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    Jan. 27 - Feb. 2, 2003 (1 week)

    Feb. 1 - 25, 2004 (3.5 weeks)

    10-11 km

    9-10km

    8-9 km

    7-8 km

    6-7 km

    5-6 km

    4-5 km

    3-4 km

    2-3km

    1-2 km

    0-1 km

    0 100 200 300

    CO (ppbv)

    In CloudAbove CloudClearBelow Cloud

    Median CO (ppbv) Enhancement in Cloudy Regions

    Clear Cloudy Enhancement

    1-5 km 135 178 32%5-11 km 101 116 15%

    0 100 200 300 400

    CO (ppbv)

    0

    1

    2

    3

    4

    5

    6

    7

    8

    9

    Altitude(km)

    0 10 20 30 40 50 60 70 80 90 100

    Relative Humidity (percent)

    0

    1

    2

    3

    4

    5

    6

    7

    8

    9

    Altitude(km)

    DC 8P-3B

    DC 8P-3BClouds may bias

    satellite estimates

    of pollution in

    Asian outflow

    observations in

    cloudy areas areneeded

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    Arctic Research of the Composition of the Troposphere fromArctic Research of the Composition of the Troposphere from

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    DC-8

    P-3B

    B200

    Terra

    10:30

    Arctic Research of the Composition of the Troposphere fromArctic Research of the Composition of the Troposphere from

    Aircraft and Satellites (ARCTAS) conducted flights during SpringAircraft and Satellites (ARCTAS) conducted flights during Spring

    (Arctic Haze) and Summer (Boreal Fires)(Arctic Haze) and Summer (Boreal Fires)

    http://fuelberg.met.fsu.edu/gallery/arctas/Thule_to_Cold_Lake_+_P-3_and_Tar_Sands/thule-to-cold-lake%20030.jpg
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    LIDAR INSTRUMENTS ON THE AIRCRAFT OBSERVE ARCTIC HAZEFROM THE SURFACE TO 30,000 FEET

    Iqaluit-Fairbanks DC-8 transit, April 9;Yellow-green colors indicate Arctic haze

    Asia

    NorthAmerica

    Europe

    Fires

    Johnathan Hair, NASA/LaRC

    Other instruments on the aircraft pinpoint the origin of this haze

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    High Spectral Resolution Lidar Observations ofArctic Haze from the NASA B200 aircraft

    cloud

    cloud

    Long-range transport from mid-latitudes into the Arctic

    results in an aerosol haze (in blue) that is mixed

    throughout the troposphere.

    Intense aerosol plumes originating from fires were

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    10

    8

    6

    4

    2

    0

    Altitude(km)

    100806040200

    Aerosol Extinction (Mm-1

    )

    Median

    10th

    and 90th

    Percentile

    0.100.050.00

    Black Carbon (g/m3)

    Aerosol Extinction

    Intense aerosol plumes originating from fires were

    superimposed on the background arctic hazehow

    important are they?

    Anomalies in fire counts from MODIS and Carbon

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    Anomalies in fire counts from MODIS and Carbon

    Monoxide from MOPITT corroborate unusually strong

    fire emissions over Siberia in April 2008.

    Comparison of CALIPSO satellite observations and

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    CALIPSO (observations)

    GMAO (model)

    RAQMS (model)

    Eastern Asia (110E 130E)

    Comparison of CALIPSO satellite observations and

    models suggests that transport of aerosols to the

    arctic from Siberian

    fires is too strong inmodels .

    Sharp gradient observed by

    CALIPSO not seen in model

    predictions.

    Preliminary model results for

    carbon monoxide indicate that

    fire emissions are

    overestimated by factors of

    2 to 3. For aerosols,

    scavenging and removal by

    precipitation is an additional

    concern requiring attention.

    Closing points:

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    0

    5

    10

    15

    20

    25

    1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

    Area Burned over Time (M ha)

    Russia

    Canada andAlaska

    Closing points:

    ARCTAS observations show a larger than expected contribution

    from fire emissions in Spring, although this may not be

    inconsistent with recent trends in boreal fires.Models appear to do a reasonable job of reproducing observed

    carbon monoxide distributions, but require estimated fire

    emissions to be reduced by factors of 2 to 3.

    Scavenging is an additional factor critical to understanding

    aerosol impacts. What fraction

    of the aerosol transported to

    the arctic is ultimately

    deposited to the snowpack?

    V DIAL Ozone Depletion Events (ODE) 17 April 200

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    NO Low Ozone Event measured by:

    UV-DIAL orNCAR CLD

    Low Ozone Event measured by:

    UV-DIAL orNCAR CLD

    V DIAL Ozone Depletion Events (ODE) 17 April 200Extending UV DIAL measurements near surface

    UV DIAL O one

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    NO Low Ozone Event measured by:

    UV-DIAL orNCAR CLD

    Low Ozone Event measured by:

    UV-DIAL orNCAR CLD

    UV DIAL OzoneDepletion Events

    (ODE) 8 April 2008

    Extending UV DIALmeasurements near

    surface

    5/1/2006 Fli h (RF 06)

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    5/1/2006 Flight (RF 06)

    Pre-flight modeling showed Asian influenced air mass off coast

    of Northwest U.S.

    Flight plan chosen to intercept it

    Pollution seen in layer at 20,000 ft early and late in flight

    J. Jimenez, CU-Boulder

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    Forecast E al ation Ma 4 DC8

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    MOZART Forecast CO

    interpolated to flight track

    compared to preliminary

    data from DACOM*

    MOZART Forecast CO

    along flight track(Fx initialized 0502 12UTC)

    * Data from Glen Sachse, NASA Langley

    Forecast Evaluation - May 4 - DC8

    05/04 12Z Forecast: Valid for 05/05 18-24Z05/04 12Z Forecast: Valid for 05/05 18-24Z

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    05/04 12Z Forecast: Valid for 05/05 18 24Z05/04 12Z Forecast: Valid for 05/05 18 24Z

    24Z: 700 hPa18Z: 700 hPa

    L. Emmons, NCAR

    F id 5/5 18Z

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    5/ 5 00Z fo re ca st Friday, 5/5, 18Z

    1

    CO

    1 2

    CO

    23

    4

    3 4

    GEOS-Chem and FLEXPART

    forecasts were very similar to

    MOZART for this flight

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    7

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    0 100 200 300 400 5000

    1

    2

    3

    4

    5

    6

    7

    100 200 300 400 500 100 200 300 400 500 100 200 300 400 500 100 200 300 400 500

    0 250 500 750 10000

    1

    2

    3

    4

    5

    6

    250 500 750 1000 250 500 750 1000 250 500 750 1000 250 500 750 1000

    Altitude(km)

    Altitud

    e(km)

    NOy (pptv)

    PAN (pptv)

    A. Weinheimer, NCAR

    F. Flocke, NCAR

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    .

    The 2004 Alaska Fires

    MOPITT 700 hPa CO mixing ratio for the period 15-23 July, 2004,

    during the INTEX-A field campaign. The intense wildfires in Alaska

    produced plumes of carbon monoxide pollution that can be traced

    across North America and the Atlantic Ocean.David Edwards, NCAR

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    Long-range transport of smoke affects air quality

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    Comparison of MODIS and GOCART

    Pollutants from forest fires (e.g.,aerosol particles and ozone) can betransported long distances, affectingsurface air quality downwind.

    In July 2004, large forest fires

    occurred in Alaska and westernCanada. Smoke aerosols weretransported across Canada and tolarge areas of continental U.S.,affecting regional air quality.

    Event was observed by MODIS andsimulated by the GOCART model,which showed a similar pattern andintensity for aerosol optical thickness.

    MODIS AOT 550 nm 200407

    GOCART AOT 550 nm 200407

    Mian Chin, NASA GSFC

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    Taken from National Air Quality-Status and Trends through 2007 (http://www.epa.gov/airtrends/2008/)

    Ozone concentrations in ppm, 2007

    (fourth highest daily max 8-hour concentration).

    Annual average PM2.5 concentrations in g/m3, 2007

    Violations of National Ambient

    Air Quality Standards (NAAQS)

    are primarily related to ozone

    and fine particulate matter.

    * Yellow and Red symbols represent levels in violation of NAAQS

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    Aerosols Significance:

    Environmentally Important: Aerosols adverselyimpact health, reduce visibility, and acidify

    precipitation

    Chemically Important: Aerosols are critical toatmospheric removal processes.

    Climatically Important: Aerosols influence Earths

    energy balance directly through the scattering

    and absorption of radiation as well as indirectly

    through modification of clouds (e.g., distribution

    and optical properties).

    URGENT NEED TO BETTER UNDERSTANDURGENT NEED TO BETTER UNDERSTAND

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    URGENT NEED TO BETTER UNDERSTANDURGENT NEED TO BETTER UNDERSTAND

    CHANGES IN THE ARCTIC ATMOSPHERECHANGES IN THE ARCTIC ATMOSPHERE

    Receptor and accumulator of pollution fromReceptor and accumulator of pollution fromnorthern mid-latitudes continents: arctic haze,northern mid-latitudes continents: arctic haze,mercury,mercury,

    Increasing forest fires in Siberia, Canada, AlaskaIncreasing forest fires in Siberia, Canada, Alaskablanket large areas with smokeblanket large areas with smoke

    Rapid warming over the past decades fasterRapid warming over the past decades fasterthan anywhere else on Earththan anywhere else on Earth

    Arctic haze and other pollution may be anArctic haze and other pollution may be animportant contributor to the warming, withimportant contributor to the warming, withcomplicated feedbackscomplicated feedbacks

    Our goal is to test and improve the models used toOur goal is to test and improve the models used to

    predict changes in Arctic pollution and climatepredict changes in Arctic pollution and climate

    THE ARCTIC IS A BEACON OF GLOBAL CHANGE

    ining pollution transport with aircraft, models, and satellites

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    DC-8 in situ CO GEOS-Chem Column COAIRS 500 mb CO (ascending

    g p p

    Characteristics of the pollution plume: Observed at ~4-6 km

    Elevated CO, SO4, and HCN

    Source could be: anthropogenic emissions from easternAsia

    biomass burning from southernSiberia

    50 75 100 125 150 175 200ppbv

    0.5 0.9 1.3 1.7 2.1 2.51018 molec/cm2

    50 100 150 200 2500ppbv

    Jenny A. Fisher [Harvard], Glenn Diskin [LaRC], Juying Warner [UMBC]

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    Atmospheric Temperature

    and Pressure

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    O3

    h H2O

    OH

    O3

    NO NO2

    h

    Dominant Source of OH NOx Partitioning

    Tropospheric Photochemistry

    Key Roles for Ozone:

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    O3

    HO2 OH

    O3

    Oxidation of Pollutants O3 Destruction

    Tropospheric Photochemistry

    Key Roles for HOx (OH+HO2):

    h, H2O .O3 OH

    OH .

    CO, CH4, RH .

    HO2, CH3O2, RO2

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    HO2, RO2

    NO NO2

    hv

    O3

    NO

    HO2 OH

    CO

    Ozone Production HOx Partitioning

    Tropospheric Photochemistry

    Key Roles for NOx (NO+NO2):

    Simplified HOxproduction and loss scheme

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    OH HO2

    O3 CH3COCH3

    HNO3 H2O2ROOH

    hv

    H2O

    CO, O3

    NO, O3

    CH4

    NO

    hv

    NO

    NO2

    HO2RO2

    CH2O

    NMHC hv

    Example of nonlinear

    chemical behaviorNOx

    amount for peak ozoneproduction is sensitive to

    the source strength for

    radicals (OH, HO2, and RO2).

    RO2

    OH

    hv

    hv

    Simplified HOxproduction and loss scheme

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    OH HO2

    O3 CH3COCH3

    HNO3 H2O2ROOH

    hv

    H2O

    CO, O3

    NO, O3

    CH4

    NO

    hv

    NO

    NO2

    HO2RO2

    CH2O

    NMHC hv

    EXAMPLEof nonlinear

    chemical behaviorboth

    NOx amount for peak ozoneproduction and peak rate

    are sensitive to the source

    strength for radicals (OH,

    HO2, and RO2).

    RO2

    OH

    hv

    hv

    Tropospheric Ozone Photochemistry

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    O3O(1D)

    OH

    HO2CH3O2RO2

    h

    NMHCs

    HO2

    OH

    H2O

    COCH4

    F(O3) = (k[HO2] + k[CH3O2] + k[RO2]) [NO]

    D(O3) = k[O(1D)][H2O] + k[HO2][O3] + k[OH][O3]

    Net O one Tendenc F(O ) D(O )

    Tropospheric Ozone Photochemistry

    NO2

    NO

    h

    HO2, CH3O2, RO2

    O2