Table 1. Instrumentation and Measurement Parameters During ICARTT Instrument Measurement Measured Property Measurement Principle Forward scattering spectrometer probe (FSSP) cloud droplet number distribution geometric diameter: 1.5-37 mum optical forward scattering Cloud, aerosol, and precipitation spectrometer (CAS) cloud droplet number distribution geometric diameter: 0.5-50 mum optical forward scattering and 2-D imaging Condensation particle counter (CPC) aerosol number concentration geometric diameter > (3 nm, 7 nm, 13 nm) varying supersaturations of butanol Dual automated classifier aerosol detector (DACAD) aerosol size distribution geometric diameter: 10-800 nm classification by electrical mobility Passive cavity aerosol spectrometer probe (PCASP) aerosol size distribution geometric diameter: 100-2500 nm optical scattering Aerodynamic particle sizer (APS) aerosol size distribution aerodynamic diameter: 500-10,000 nm aerodynamic classification Three-column cloud condensation nuclei counter (CCN) CCN concentration three supersaturations activation at constant supersaturation; optical detection of droplets Aerodyne aerosol mass spectrometer (AMS) aerosol chemical composition mass concentration: SO42-, NH4+, NO3-, OC Flash ionization; quadrapole mass spectrometer Particle-into-liquid sampler (PILS) aerosol chemical composition mass concentration: SO42-, NH4+, NO3-, oxalate ion chromatography C-Navigational System and Novatel GPS updraft velocity, wind speed wind velocity; aircraft position and altitude wind velocity = aircraft ground velocity (C-MIGITS INS/GPS) - aircraft air velocity (turbulence and Pitot-static probes)