HR: 1340h
AN: A33B-0904 [Abstracts]
TI: Dependability of Electrochemical Concentration Cell (ECC) Measurements
AU: * Schmidlin, F J
EM: fjs@osb.wff.nasa.gov
AU: Northam, E T
EM: northam@osb.wff.nasa.gov
AU: Baldwin, T M
EM: tony.m.baldwin@nasa.gov
AB:
It is known that valid measurements from the Electrochemical Concentration Cell (ECC) ozonesonde instrument depend on the
control exercise over the pre-flight preparation procedure. NASA Wallops Flight Facility uses preparation procedures designed
to detect anomalies that could interfere with obtaining valid ozone profiles. The major factors considered during
preparation of an ECC are pump efficiency calibration, volumetric flow rate check, and maintenance of a low background
current. Some pre-flight parameters are provided by the manufacturer; nonetheless, these are reconfirmed before they are
used. The ECC, prior to release is compared against a well calibrated UV photometer and the offset applied, if desired. The
advantage of this pre-release calibration and recent steps to improve the technique are discussed. Preparation of the ECC
instrument begins 3-4 weeks prior to the day of observation and the procedure iterated once a week until release occurs. We
briefly describe the instrumental tests employed, discuss the effect of different sensing solution concentrations from dual
instrument flights, as well as from improved laboratory tests. Comparison of ECC measurements against surface-(Dobson
Spectrophotometer) and space-based (AQUA, AURA, and EP-TOMS) measurements are included in our discussion. We postulate
reasons for differences, which, in spite of excellent ozonesonde pre-flight quality control and automated data analysis, may
be due to uncertainties in both measuring systems.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0365 Troposphere: composition and chemistry
DE: 0394 Instruments and techniques
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005