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U.S. AIRCRAFT CAMPAIGNSU.S. AIRCRAFT CAMPAIGNS
Daniel J. Jacob
OBSERVATION PLATFORMS FOR ATMOSPHERIC COMPOSITIONOBSERVATION PLATFORMS FOR ATMOSPHERIC COMPOSITION
SURFACE SITES, SHIPS
SONDES, LIDARS
AIRCRAFT SATELLITES
Horizontal coverage
- - + +
Temporal coverage
+ + - +
Vertical range - + = (up to ~20 km)
= (interferences)
Vertical resolution
none + + -
Chemical detail + - + -Surface fluxes + - + +
(by inversion)
Cost + + = -
AIRCRAFT FLIGHT STRATEGIESAIRCRAFT FLIGHT STRATEGIES
Characterization of emissions, surface uptake
Process studies:• photochemistry• plume evolution• transport mechanisms
Satellitevalidation Air mass
characterization• global and regional chemical budgets• long-range transport
Remote sensing:• mapping of surface,atmosphere• satellite validation
NASA GTE TROPOSPHERIC CHEMISTRY MISSIONSNASA GTE TROPOSPHERIC CHEMISTRY MISSIONS
Other important global tropospheric missions: NASA/SONEX (North Atlantic), NSF/TOPSE (Arctic), NSF/ACE (Atlantic, Pacific),NOAA/ITCT-2K2 (E. Pacific)…
100 E 130 E 160 E 190 E 220 E 250 E 280 E
Longitude
0 N
10 N
20 N
30 N
40 N
50 N
60 N
La
titu
de
DC-8 FlightsP-3B Flightsoutbound
inbound
THE NASA/TRACE-P AIRCRAFT MISSION (Mar—Apr 2001)THE NASA/TRACE-P AIRCRAFT MISSION (Mar—Apr 2001)Characterize Asian chemical outflow and evolution;
place top-down constraints on sources
Two instrumented aircraft (DC-8 and P-3) operating out of Hong Kong and Yokota AFB (Japan)
THE NASA DC-8 “Flying Laboratory”THE NASA DC-8 “Flying Laboratory”
NASA DC-8 – the insideNASA DC-8 – the inside
TRACE-P DC-8 PAYLOADTRACE-P DC-8 PAYLOADEmphasis:high altitude outflow,large-scale mapping,photochemistry
PAN, carbonyls, alcohols
aerosols
NO, NO2
OH, HO2
Actinicfluxes
Carbonyls, alcohols
O3+aerosolDIAL
NMHCs,Halocarbons,DMS
HCHO
CO2, O3
Aerosols, SO2, HNO3
H2O, CO, CH4,N2O
H2O2, CH3OOH, HCHO
TRACE-P P-3 PAYLOADTRACE-P P-3 PAYLOAD
Emphasis:low altitude outflow,sulfur/aerosols,fluxes to ocean
Aerosols
H2O NO, NO2
NMHCs,Halocarbons,DMS
SO2, DMS
PAN, PPNActinic fluxes
CO, CH4
Vertical winds
O3, CO2
aerosolsH2SO4, MSA,OH, HNO3,HO2, RO2
TRACE-P INVOLVED THE INTEGRATION OF AIRCRAFT, TRACE-P INVOLVED THE INTEGRATION OF AIRCRAFT, SATELLITES, MODELS, AND EMISSION INVENTORIESSATELLITES, MODELS, AND EMISSION INVENTORIES
TRACE-P CO DATA(G.W. Sachse)Bottom-up
emissions(customized for TRACE-P)
Fossil and biofuel Daily biomass burning(satellite fire counts)
Chemical Transport Model (CTM)
MOPITT CO
Inverse analysis
validation
chemicalforecasts
top-downconstraints
OPTIMIZATION OF SOURCES
Example: improving constraints on Asian CO sources
Streets et al. [2003] Heald et al. [2003a]
MOPITT VALIDATION DURING TRACE-PMOPITT VALIDATION DURING TRACE-P
• Seven DC-8 vertical profiles (0.15-10 km) coincident with MOPITT overpass• Spirals of 20 km diam. matching MOPITT FOV• Double spirals to verify stationarity of features• One DC-8 transect along orbit track
Example (March 20)
TRACE-P validation spirals + transectMOPITTunderpass
MOPITT VALIDATION PROFILES DURING TRACE-PMOPITT VALIDATION PROFILES DURING TRACE-P
Aircraft Aircraft w/av. kernels
MOPITT (v3, x = ±100 km)
Averagingkernels
TRACE-P VALIDATION PROFILES:TRACE-P VALIDATION PROFILES:MOPITT vs. DC-8 CO columnsMOPITT vs. DC-8 CO columns
DC-8 w/avKer r2 > 0.99 DC-8 950-300 hPa r2 =0.98
CO column,
1018 molecules cm-2
MOPITT 2.25 ± 0.19
DC-8
w/avKer
2.12 ± 0.23
DC-8
950-300 hPa
1.58 ± 0.19
6% positive bias in MOPITT column data
Jacob et al. [2003]
COMPARATIVE INVERSE ANALYSIS OF ASIAN CO SOURCES COMPARATIVE INVERSE ANALYSIS OF ASIAN CO SOURCES USING DAILY MOPITT AND TRACE-P DATA USING DAILY MOPITT AND TRACE-P DATA
• MOPITT and TRACE-P both show underestimate of anthropogenic emissions (40% for China, likely due to under-reporting of industrial coal use)
• MOPITT and TRACE-P both show overestimate of biomass burning emissions in southeast Asia ;very low values from TRACE-P could reflect transport bias
• MOPITT has higher information content than TRACE-P because it observes source regions and Indian outflow
• MOPITT information degrades if data are averaged weekly or monthly • Ensemble modeling of MOPITT data indicates 10-40% uncertainty on retrieved sources
Heald et al. [2004]
CO observations from Spring 2001, GEOS-CHEM CTM as forward model
TRACE-P Aircraft CO MOPITT CO Columns
4 degreesof freedom
10 degreesof freedom
(from validation)
ASIAN HALOCARBON EMISSIONS (CHASIAN HALOCARBON EMISSIONS (CH33CClCCl33, CCl, CCl44, ,
Halon 1211, CFCs) DEDUCED FROM TRACE-P DATAHalon 1211, CFCs) DEDUCED FROM TRACE-P DATA
CH3CCl3 CCl4
TRACE-P PBL halocarbon observationsBack-trajectories for top 5% of CH3CCl3 PBL data; Seoul and Shangai are principal sources
Halocarbon emissions deduced from relationships with CO
• Eastern Asian source of CCl4 deduced from TRACE-P data is 5 times higher than UNEP estimate; other halocarbons are consistent with UNEP• Correction to CCl4 emission implies a 40% increase in total ODP-equivalent emissions from eastern Asia
Palmer et al. [2003]
TRANSPACIFIC TRANSPORT OF ASIAN TRANSPACIFIC TRANSPORT OF ASIAN CO AND OZONE IN TRACE-P: CO AND OZONE IN TRACE-P:
Feb 26-27, 2001 PLUMEFeb 26-27, 2001 PLUME
MOPITT 500 hPa CO, Feb 26
TRACE-P profiles,Feb 26-27
COOzone
1
1
2
23
3
45
4
5
Heald et al. [2003b]
Ozone CO
Aircraft track
Asian plume
NOAA/ITCT-2K2 AIRCRAFT CAMPAIGN IN APRIL-MAY 2002 NOAA/ITCT-2K2 AIRCRAFT CAMPAIGN IN APRIL-MAY 2002 Monterey, CAMonterey, CA
High-ozone Asian pollution plumes observed in lower free troposphere but not at surface (Trinidad Head);strong stratospheric influence (Trinidad Head sondes)
CO
O3
PAN
HNO3
May 5 plume at 6 km:High CO and PAN,no O3 enhancement
May 17 subsidingplume at 2.5 km:High CO and O3,PAN NOxHNO3
Hudman et al. [2004]
Observations by D. Parrish, J. Roberts, T. Ryesrson (NOAA/AL)
DIURNAL AND CONVECTIVE INFLUENCES ON HODIURNAL AND CONVECTIVE INFLUENCES ON HOxx
RADICALS OVER PACIFICRADICALS OVER PACIFICPEM-Tropics B DC-8 flight NW of Tahiti on April 7, 1999
Fly back-and forth “shoelace” pattern for 4 hours
Background:12% RH80 ppt H2O2
60 ppt CH3OOH
Conv. influence:35% RH80 ppt H2O2
290 ppt CH3OOH
Observations (W. Brune)Photochemical modelModel with k(CH3O2+HO2) x3+
• HOx at sunrise behaves as expected;• strong HOx source from photolysis of convected CH3OOH;• need additional HOx sink to match observations
Ravetta et al. [2002]
ICARTT: COORDINATED ATMOSPHERIC CHEMISTRY CAMPAIGN OVER ICARTT: COORDINATED ATMOSPHERIC CHEMISTRY CAMPAIGN OVER EASTERN NORTH AMERICA AND NORTH ATLANTIC IN SUMMER 2004EASTERN NORTH AMERICA AND NORTH ATLANTIC IN SUMMER 2004
International, multi-agency (U.S.) collaboration targeted at U.S. regional air quality, pollution outflow, transatlantic transport, aerosol radiative forcing
Terra
ERS
MISR, MODIS, MOPITT
ERS-2
GOME
Envisat
SCIAMACHY
Aqua
AIRS, MODIS
NASA DC-8
UK BAE-143
DLR Falcon
NOAA-P3DOE G-1
NASAProteus
NRT
O3
HNO3
CH2O
CO
HIGH FREE HIGH FREE TROPOSPHERIC TROPOSPHERIC
OZONE OVER OZONE OVER SE U.S. SE U.S.
OBSERVED OBSERVED IN ICARTTIN ICARTT
July 12 DC-8 flight from St. Louis
High ozone appears tropospheric in origin
PREDICTED UPPER TROPOSPHERIC OZONE MAXIMUM PREDICTED UPPER TROPOSPHERIC OZONE MAXIMUM OVER MIDDLE EAST IN SUMMER: HOW TO TEST?OVER MIDDLE EAST IN SUMMER: HOW TO TEST?
GEOS-CHEM tropospheric ozone column, July 1997
Comparison to MOZAIC observations aboard commercialaircraft, 1995-2000
Jul (red), Jan (blue),model (solid), obs (dotted)
Li et al. [2001]
FUTURE TROPOSPHERIC CHEMISTRY MISSIONS: FUTURE TROPOSPHERIC CHEMISTRY MISSIONS: INSTRUMENT NEEDSINSTRUMENT NEEDS
• Fast instrumentation for NH3, bulk aerosol composition including organics
• Improved precision/accuracy for HOx radical measurements, capability for CH3O2 measurements
• Improved confidence in measurements of SO2, bulk aerosol composition, aldehydes, peroxides
• CO lidar
THE FUTURE OF U.S. AIRCRAFT MISSIONSTHE FUTURE OF U.S. AIRCRAFT MISSIONS
•DC-8 to remain an important platform in near future: NASA INTEX-B in spring 2006
•Probing the upper troposphere/lower stratosphere using aircraft with 18-20 km ceilings and tropospheric measurement capability: NSF HIAPER, NASA WB-57
• Routine and cheap vertical profiling using small aircraft (e.g., Cessna)
• Air sampling packages on commercial aircraft (European MOZAIC program has been a big success)
• Global monitoring using remotely piloted vehicles (RPVs)
RPV Capability Development Timeline
HALE-ROA Capability Set • 14 days @ 60-70K ft• 400-lb Payload• Autonomous Operations
10-Year Capability Set • 100 days @ 75K ft• 1000-lb Payload• Autonomous Operations• Collaborative Engagement
Full Capability Set • Heavy Lift• 100 days @ > 60K ft• Autonomous Operations• Collaborative Engagement
Current SOA: • 60K ft @ 14 hrs - 200-lb• 100K ft @ 1 hrs - 100-lb• Pre-Programmed
Required Technologies @ TRL 6
FY09 FY14 FY19Current timeline