Modeling Elevated Upper Tropospheric Ozone Due To Deep

Convection During the 2006 AEROSE II Cruise

Jonathan W. Smith1,2, Gregory S. Jenkins1, Kenneth E. Pickering2, Mary C. Barth3

1.Howard University (HU) 2. NASA/GSFC 3. NCAR/ACD

1st DC-AMS Joint Meeting with HU, UMD-CP, and UMBCWednesday, February 17, 2010

Outline• Overview of enhanced upper tropospheric ozone sources

• Convective transport of biomass burning (BB) constituents

• Convection and nitrogen oxide production from lightning (LNOx)

• BB, convection, and LNOx

• Ideal study location

• WRF-Chem Methodology

• Proposed LNOx sensitivity tests in WRF-Chem

• Hypotheses

Overview of enhanced upper tropospheric ozone sourcesAghedo et al. 2007 Table 1

CONVECTIVE TRANSPORT OF

BB CONSTITUENTS

MODIS Rapid Response – Global Fire Map 31 May – 09 June 2006

MODIS Aura 30 MAY 2006

Angola

Democratic Republic of Congo

Zambia

CongoConvection

Positive Carbon Monoxide

(CO) Anomaly

Max Ozone Production

(longer lifetime)

N SFires

Convective Transport of BB Constituents

Fire Constituents

Outflow Region

1000 hPa

200 hPa EasterlyBackground

Wind(Out of screen)

Ascension Island (7 S 14 W) 1430 Z 14 June 2006 SHADOZ Data

90 ppbv around 250 – 300 hPa

CONVECTION AND LNOx

Lightning flashes per square km over an 11 – year period

Credit: NASA/Marshall Space Flight Center's Lightning Imaging Sensor Science Team, NASA's Optical Transient

Detector and TRMM's Lightning Imaging Sensor

WWLLN detected 203,416 cloud to ground (CG) strikes In this region during June 2006

Ozone Production

W E

LNOx

Outflow Region

1000 hPa

200 hPa

250 Moles of NO per Flash (Schumann and Huntrieser [2007])

NO + HO2 radicalNO2 photolysis

NOx has longer lifetime

Easterly Background Wind

CG Strikes

IC Strikes

AEROSE II Cruise Ozonesonde Launch Position Along 23 W (Morris et al. 2007)

4.16 S – 1430 UTC – 15 June

0.51 S – 0133 UTC – 14 June3.50 N – 1346 UTC – 11 June

2.76 S – 1426 UTC – 26 June

2.36 N – 0234 UTC – 29 June

3.56 N – 1454 UTC – 29 June

1st Leg

2nd Leg

BBCONVECTION

AND LNOx

Fire and Lightning

Jenkins et al. 1997, JGR

Jenkins et al. 2008, GRL, Figures 1 b

Ideal Study Location and WRF-Chem Model Domain

Fire emissions Deep Convection

Significant CG Lightning Strikes

Tool: WRF-Chem - dx, dy = 25 km

WRF-Chem Model MethodologyWRF-CHEM MODEL

PARAMETERSBB RUN

SCHEMES

Start and End Time 00 Z 25 May 2006 to 00 Z 01 July 2006

Meteorology Initial/Boundary Conditions

GFS Final Analysis (1.0° x 1.0°)

Chemistry Initial/ Boundary Conditions MOZART (Global Model)

Chemical Mechanism CBM-Z/MOSAIC

Microphysics Thompson graupel scheme

Cumulus New Grell

PBL Scheme MYJ

Surface Physics Noah Land Surface Model

Photolysis Madronich F-TUV

# of Eta Levels 50

Top of Model 10 hPa

Model Output Interval 3 hours

Proposed LNOx Sensitivity Tests in WRF-Chem

Calculate anomalous quantities of NOx and ozone in the upper troposphere generated from placing CG strikes

into each model grid cell using 250 moles NO/flash (Schumann and Huntreiser, 2007)

Investigate whether methods employed by Amanda Hansen et al. can be used to parameterize lightning flash

rates with the New Grell convective scheme

Calculate differences in LNOx production when lightning is placed in grid cells vs parameterization

Hypotheses• Deep convection overlaps with fires in the Congo, Democratic Republic of Congo, and

northern Angola

• 2 – 4 days for anomalous CO plumes ejected by deep convection to reach 1000 km into the Central Atlantic Ocean (Pickering et al. 1996)

• BB is a significant producer of ozone in the upper troposphere - > should increase ozone by 30 - 40 ppbv over the background (Dickerson et al. 1987, Pickering et al. 1996)

• The easterly flow of LNOx at 300 hPa is transported to 23 W hence leading to a coupled BB constituents and LNOx enhancement of ozone (Jenkins and Ryu 2005, and Savauge et al. 2007)

• Positive CO and Ozone anomalies will exist simultaneously but the ozone anomaly will be downwind of CO anomaly and convective cell (Dickerson et al. 1987)

• Results could provide a rough quantitative figure on how much LNOx contribution to enhanced Ozone and the global NOx budget in general

• Results could provide guidance on the percentage of ozone enhanced by LNOx (natural source) vs BB (anthropogenic source)

Acknowledgements

Gabi Pfister – ACD/NCAR

Christine Wiendenmeyer - ACD/NCAR

Jeff Lee – ACD/NCAR

Steve Peckham – NOAA

Robjhon Miliaritania – Howard University

Everette Joseph – Howard University

Nick Nalli - NOAA

NSF ATM Grant - 621159

QUESTIONS