R. C. Hudman, D. J. Jacob, S. Turquety, Lee Murray, ITCT-2K4 science team, INTEX-NA science team
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R. C. Hudman, D. J. Jacob, S. Turquety, Lee Murray, ITCT-2K4 science team, INTEX-NA science team A multi-platform analysis of the North American reactive nitrogen budget during the ICARTT summer intensive NEAQS/ITCT2k4 rements: M. Avery, R. Cohen, J. Dibb, F. Flocke, J. Holloway, A. Neu T. Ryerson, G. Sachse, H. Singh, P. Wennberg ICARTT science meeting GEOS-CHEM - NEI-99 emissions (VOC modifications) - 2x2.5 resolution
description
A multi-platform analysis of the North American reactive nitrogen budget during the ICARTT summer intensive. R. C. Hudman, D. J. Jacob, S. Turquety, Lee Murray, ITCT-2K4 science team, INTEX-NA science team. Measurements: M. Avery, R. Cohen, J. Dibb, F. Flocke, J. Holloway, A. Neuman,. - PowerPoint PPT Presentation
Transcript of R. C. Hudman, D. J. Jacob, S. Turquety, Lee Murray, ITCT-2K4 science team, INTEX-NA science team
R. C. Hudman, D. J. Jacob, S. Turquety, Lee Murray, ITCT-2K4 science team, INTEX-NA science team
A multi-platform analysis of the North American reactive nitrogen budget during the ICARTT summer intensive
NEAQS/ITCT2k4
Measurements: M. Avery, R. Cohen, J. Dibb, F. Flocke, J. Holloway, A. Neuman,
T. Ryerson, G. Sachse, H. Singh, P. Wennberg
ICARTT science meeting
GEOS-CHEM
- NEI-99 emissions (VOC modifications)
- 2x2.5 resolution
ICARTT 0-2 km NOy* partitioning:Rapid Oxidation of NOx downwind of continent
PAN/NOy
NOx/NOy
Merged Observations GEOS-CHEM
Rapid NOx oxidation
NE/MW: 25% South: 18% OffShore: 15%
HNO3/NOy
NE/MW: 19% South: 20% OffShore: 10%
NE/MW: 56% South: 62% OffShore: 74%
Large NOx sources
*“NOy”=NOx + HNO3 + PAN
ICARTT 4-8 km NOy partitioning:Role of PAN increases
PAN/NOy
HNO3/NOy
Observed Modeled
NOx/NOy
PAN in outflow
ICARTT 8+ km NOy partitioning:Large Lightning Presence
PAN/NOy
Observed Modeled
NOx/NOy
PAN dominates outflow
HNO3/NOy
GEOS-CHEM vs. INTEX-NA and ITCT2k4:Comparison along the flight tracks*
•local, strat, BB filteredGridded tp 2x25
NO2 underestimate above 6 km
Overestimate of CO & NOx anthro. source
Similar PAN underestimate
O3 FT bias
PAN bias: Background or NA Enhancement?PAN - CO correlations in free tropopshere
ModeledObserved
Top:
Bottom: Modeled Tagged tracer correlations 6-8 km
PAN discrepency in enhancement
[Q. Liang, UW]
PAN correlation dominated by NA tracer
July Total (Tg N)
Global
Aircraft Source July (Tg N): .05, Yearly ~ .5
Lightning Source July (Tg N): .5, Yearly ~ 5
U.S.
Aircraft Source July (Tg N): .012
Lightning Source July (Tg N): .067
Relative Importance of Upper trop NOx sources: July Lightning and Aircraft Totals
LI ~ 5 x Aircraft
IPCC Aviation and Global Atm (1999)
1992 ~.5
2015(proj) ~1.0
Most we can increase aviation srce x2
NOT ENOUGH!
Insufficient Convection? …not likelyPropane – NO2 correlations in BL and 8-10 km
OTD/LIS Climatology and GEOS-CHEM 2004
Factor of two underestimate above 35 N over U.S.
Mean July flash rate
OTD/LIS GEOS-CHEM
[Flashes/km2/day]
ZMMU (REAL*8 ) : GEOS-4 Z&M updraft mass flux [Pa/s]
20
10
Alt
itud
e (k
m)
-50 50 -50 50
CLDMAS (REAL*8 ) : Cloud mass flux [kg/m2/600s]
Latitude
Cloud Top Height (CTH) is calculated as where these values go to zero, respectively.GEOS4 convective cloud heights do not reach tropopause
tropopause height
Mean CLDMAS and ZZMU: GEOS4 low cloud heights illustrated Convective Mass Flux GEOS-4 vs. GEOS-3: Vertical Placement of NOx emissions greatly influences mean [NOx]
Different assumptions in the vertical placement of lightning NOx 50% increase in mean [NOx]
O3 vs. CO correlation 0-2 km: All INTEX and ITCT-2K2 data
All Data
South
Northeast
Lower O3/CO correlation in South
[Lee Murray]
RMA slope = .47
R^2 = .49
RMA slope = .47
R^2 = .5
RMA slope = .35
R^2 = .3
