|
Detailed Reference Information |
Ryerson, T.B., Huey, L.G., Knapp, K., Neuman, J.A., Parrish, D.D., Sueper, D.T. and Fehsenfeld, F.C. (1999). Design and initial characterization of an inlet for gas-phase NOy measurements from aircraft. Journal of Geophysical Research 104: doi: 10.1029/1998JD100087. issn: 0148-0227. |
|
An understanding of gas-phase HNO3 transmission through an inlet is necessary to evaluate the quality of NOy measurements from an aircraft platform. A simple, inexpensive, low-volume Teflon inlet is described and its suitability as an aircraft inlet for gas-phase NOy is assessed. Aerosol transmission is not characterized, but inlet design and orientation probably discriminates against the majority of aerosol by mass. Laboratory data, in-flight HNO3 standard addition calibrations, and ambient NOy measurements from the 1997 North Atlantic Regional Experiment aircraft mission are used to characterize inlet transmission efficiencies and time constants. Laboratory tests show high transmission efficiencies for HNO3 which are relatively independent of ambient temperature and humidity. In-flight standard addition calibrations were carried out at ambient temperatures ranging from -20¿ to +8 ¿C and relative humidities from 3% to 71%. These data suggest that nearly all the sampled air contacts an inlet surface, with 90% of added HNO3 being transmitted in ~1.5 s. Ambient data are presented to demonstrate negligible hysteresis in 1-Hz NOy measurements, relative to variability observed in ozone data, from an air mass where HNO3 is expected to be a large fraction of the total NOy. Power spectra of ambient NOy (at temperatures from -35¿ to +35 ¿C and relative humidities from 3% to 100%) and ozone measurements suggest an effective NOy instrument time constant of ~2 s. ¿ 1999 American Geophysical Union |
|
|
|
BACKGROUND DATA FILES |
|
|
Abstract |
|
|
|
|
|
Keywords
Atmospheric Composition and Structure, Constituent sources and sinks, Atmospheric Composition and Structure, Troposphere—composition and chemistry, Atmospheric Composition and Structure, Pollution—urban and regional, Meteorology and Atmospheric Dynamics, Numerical modeling and data assimilation |
|
Publisher
American Geophysical Union 2000 Florida Avenue N.W. Washington, D.C. 20009-1277 USA 1-202-462-6900 1-202-328-0566 service@agu.org |
|
|
|