MAOS (Mobile Aerosol Observing System) and the G1 Aircraft at Cape Cod Allie Marquardt Collow

MAOS

InstrumentMeasurement Radar Wind ProfilerWind speed and direction profiles using 1290Mhz and 915Mhz SodarWind velocity and direction in the lower atmosphere Aerosol SpectrometerAerosol size and number from 50nm to 1 micron Dual Column CCN CounterNumber of aerosols that activate to become cloud condensation nuclei two independently selectable supersaturations Single Particle Soot PhotometerBlack Carbon mass, size and composition, and single particle scattering of non- absorbing particles Scanning Mobility Particle SizerAerosol Size Distribution from 15 to 450 nm Photo-Acoustic Soot SpectrometerAerosol absorption and scattering coefficient HumidigraphAerosol scattering coefficient as a function of relative humidity NephelometerAerosol extinction coefficient Condensation Particle Counter (10 to >3000nm size range) Condensation particle concentration, 10nm to >3000nm Condensation Particle Counter (2.5 to >3000nm size range) Condensation particle concentration, 2.5nm to >3000nm Hygroscopic Tandem Differential Mobility Analyzer Aerosol growth factor as a function of humidity Particle Soot Absorption PhotometerAerosol absorption coefficient 7-Wavelength AethelometerOptical Absorption Weather TransmitterTemp, RH, wind speed and direction, rainfall, barometric pressure Trace Gas Instrument SystemCO, SO2, NOx Concentrations Particle into Liquid Sampler-ion Chromatography-water soluble organic carbon Aerosol chemical composition, anions, cations, water soluble organic carbon Proton Transfer Mass SpectrometerVolatile Organic Compounds Aerosol Chemistry Speciation MonitorAerosol mass and composition

MAOS Aerosol Chemistry Speciation Monitor(ACSM) An aerodynamic lens samples and focuses submicron particles The focused particle beam enters two more chambers where particles impact and flash vaporize on a hot oven Particles are then detected and chemically characterized using 70eV electron impact quadrupole mass spectrometry An Aerosol Chemical Speciation Monitor (ACSM) for Routine Monitoring of the Composition and Mass Concentrations of Ambient Aerosol, N. L. Ng, S. C. Herndon, A. Trimborn, M. R. Canagaratna, P. L. Croteau, T. B. Onasch, D. Sueper, D. R. Worsnop, Q. Zhang, Y. L. Sun and J. T. Jayne,, Aerosol Sci. Tech., 45, , DOI: / , Sensitivity (μg m-3, 30 minute, 3σ ): Organic: 0.3 Sulfate: 0.4 Nitrate: 0.2 NH4: 0.5 Chloride: 0.2

MAOS

9 Possible Atmospheric Research Flights for the TCAP campaign July 7-30, No flights are planned within 30nm of either BOS or NY Class B Airspace

MAOS Marine Boundary Layer Altitude (not to scale) Cape Cod (with AMF/MAOS) Ocean Schematic of G-1 flight plan UFT (~10,000 ft MSL or AOD = 0.01) MFT (~ ½ UFT) LFT (~ 1km) UBL (~ 05. km) LBL Free Atmosphere (~60km/ 10 min) KHYA (Barnstable Airport) LBL = lower (marine) boundary layer MBL = middle (marine) boundary layer LFT = lower free troposphere MFT = middle free troposphere UFT = upper free troposphere spiral down B200 G-1 Instruments in excel file

MAOS G-1 Cabin Layout

MAOS SPLAT II Creates a focused particle beam using an aerodynamic lens inlet Two stages of differential pumping separate particles and gas Two stages of optical detection use light scattering to detect each particle twice and to measure its velocity, from which the particle aerodynamic diameter is obtained. Pulsed, synchronized IR evaporation followed by UV ionization of semi-volatile fractions and ablation of non-volatile fractions creates ions. From these ions, time-of-flight mass spectra are generated for compositional analysis /viewInstrument.jsp?id=34020