modeling elevated upper tropospheric ozone due to deep convection during the 2006 aerose ii cruise...
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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