DC-8 SEAC4RS Payload & CapabilitiesHanwant Singh, ARC

Assumes 8 h DC-8 round trip with some loiter time

UTAPAO

Multiple flight clearances needed

IN MM

TLBB

NP

VNCB

BD

TBIN

ML

IA

DC-84 Engine JetCeiling 12.5 km (0.5-41Kft)Range 10000 kmTrue air speed 250-450 kntsTurning radius 15-30 km (<10° BA)Nominal flights 8-9 hours

DC-8 SEAC4RS Payload (26 instruments)

Investigator Acronym Measurement Type Principal, sensitivity, resolutionRyerson CSD CL NO, NO2, NOy, O3 In Situ chemiluminescence; 10 ppt; 1-sCohen TD-LIF NO2, Sum-Nitrates In Situ Fluorescence; 10 ppt; 1-sHuey GT-CIMS PANs, SO2 In Situ Ionization-spectroscopy; 10 ppt; 10-sDibb SAGA* HNO3, bulk aerosols In Situ Ion-chromatography; 10 ppt; 120-sWennberg CIT-CIMS HNO3, HCN, peroxides, o-acids In Situ Ionization-spectroscopy; 10 ppt, 1-sFried DFGAS Formaldehyde In Situ IR-Spectrometer; 10 ppt; 15-sHanisco ISAF Formaldehyde In Situ Fluorescence; 10 ppt; 1-sWisthaler PTR-MS Select OVOC, NMHC, CH3CN In Situ Ionization-spectroscopy; 10 ppt, 10-sBlake WAS* Hydro and halo carbons In Situ Gas-chromatography; low ppt, 120-sDiskin DACOM CO, CH4, N2O In Situ TDL-spectroscopy, low ppb, 1-sBeyersdorf AVOCET CO2 In Situ Non-dispersive IR, 100 ppb, 1-sDiskin DLH Water vapor Remote Open-path Spectroscopy, 1 ppm, 1-sHair DIAL HSRL O3 and aerosol profiles Remote Up/down lidar ozone and aerosol profilesJimenez AMS TOF-Aerosol mass spectra In Situ Fine aerosol (SO4, NO3, OA), 0.1 ng/m3, 10-sGao HD-SP2 Black carbon aerosol In Situ laser-induced incandescence, 1 ng/m3, 60-sMurphy PALMS Single particle composition In Situ ionization mass spectrometer, 0.2-3 mm, 100-HzAnderson LARGE Aerosol measurements (CN, CCN) In Situ Particle counters, 0.01-10 mm, 1-sSorooshian DASH-SP Aerosol hygroscopicity In Situ Differential mobility, growth factors, 10-2500 nmBrock AOP Aerosol extinction and absorption In Situ Cavity ring down/photoacoustic, 405-660 nmLawson SPEC Aerosol parameters Remote Particle imagingTanelli APR-2 Precipitation, clouds Remote 13.4 & 35.6 GHz RADARRussell AATS-14 Aerosol optical depth Remote Sun photometer, 350-2100 nm; 2-6 nm resolutionBucholtz BBR Broadband solar and IR Remote Up/down solar/IR irradiance, hemispheric, 10-HzSchmidt SSFR Solar and near IR irradiance Remote Up/down radiometer, 380-2200 nm, 10 nm resol.Hall CAFS Actinic flux Remote Spectral radiometers, 280-680 nm, 2 nm resol.Bui MMS Micromet (T, P, wind vectors) In Situ Winds, temperature, pressure, 100-Hz

DC-8 SEAC4RS Payload

Mission Mgr. Console

NavigationCIT-CIMS

AOP

LARGE

HD-SP2DASH-SPPALMS AMS

ISAF TD-LIFGT-CIMS

CSDL-CLDACOMDLH SAGA

AVOCETAPR-2

DFGASMMSSPEC

PTR-MSWAS SSFR

BBRAATS-14(4STAR)

MSCAFS

DIAL

O3/NOy

HCHO

DIAL

Instrument channels & probes• AOP (3 instruments): (1) cavity ring-down extinction spectrometer,

(2) photo acoustic absorption SPTR, and (3) aerosol size SPTR• GT-CIMS (2 instruments): (1) SF5

- CIMS for SO2 (HCl, HNO4) and (2) I- CIMS for PANS

• LARGE: Multiple probes

75 organics on the DC-8

• PTR-MS: CH3CN, acetone, methanol, acetaldehyde, benzene, toluene, isoprene, pinenes, MVK

• CIT-CIMS: HCN, CH3OOH, CH3COOH, HCOOH, some oxygenated carbonyls

• GT-CIMS: PANs {RC(O)OONO2}• WAS: C2-C10 NMHC, C1-C5 RONO2, C1-

C2 halocarbons, OCS• AMS: Organic aerosol

Observed groups on the DC-8

• Tracers: CH3CN, HCN, CO, CO2, SO2, halocarbons (CH3I/CHBr3), NOy, some NMHC, aerosol

• Photochemical/O3 precursors: O3*, NO2, HNO3, HCHO, NO, PANs, HNO4, OVOC,C1-C10 HCs, H2O2, CH3OOH

• Greenhouse gases: CO2, CH4, N2O, O3, H2O• Aerosol composition: SO4, NO3, BC, NH4, OA• Aerosol properties: CN, hot-CN, CCN, hygroscopicity,

absorption, extinction, scattering, clouds/precipitation• Radiation: Actinic fluxes, AOD, solar and IR irradiances

*Duplicate DC-8 measurements in red

Downlinking DC-8 data for flight coordination

Many DC-8 PIs are agreeable to transmitting data to the ground but will need help to facilitate this process. Most have not done it before.

Need to optimize this activity taking into account bandwidth constraints and usefulness for ground planners.

Present feasible candidates are:• DIAL curtains • CO, O3, NOy, H2O• Hot/cold FCN, SO4• State variables (T, P, Lat/Long, Alt, 3-D winds)• Feasible but lower priority (CH4, SO2, PAN, BC,

OA, CO2, NO, total-SCAT, UFCN, AOD etc.)

O3 Aerosol Scat

Examples of gas & aerosol composition from DC-8

Some comments & observations/DC-8Excellent DC-8 range & state of the art gas/aerosol

composition package to address main SEAC4RS goals of;- Megacity/BB pollution outflow and its evolution;- Inflow, outflow & processing by deep convective

systems; - Asian monsoon anticyclone composition and chemistry;- Cirrus layer heating rates & UTLS influences- SAT Cal/Val

Coordinated platform flights will be central to achieving SEAC4RS objectives

SEAC4RS goals will benefit from:- Smooth DC-8 in flight communications with ground and

possibly other A/C- Sorting data transmission and instrument inter-

comparison issues during DC3- Suitcase flight opportunities and/or extra long flights??