ELECTROCHEMICAL CONCENTRATION CELL OZONESONDE PERFORMANCE EVALUATION DURING STOIC 1989

Electrochemical concentration cell (ECC) ozonesondes flown by NOAA and NASA Wallops Flight Facility (WFF) personnel during the Stratospheric Ozone Intercomparison Campaign (STOIC) conducted at the Jet Propulsio n Laboratory's Table Mountain Facility, Wrightwood, California, July 2 1 to August 1, 1989, exhibited highly similar ozone measurement precis ions and accuracies even though considerably different methods were us ed by the two research groups in preparing the instruments for use and in calibrating the instruments, The Table Mountain data as well as da ta obtained in the past showed the precisions to range from about +/-3 to +/-12% in the troposphere, remain relatively constant at +/-3% in the stratosphere to 10 mbar, then decrease to about +/-10% at 4-mbar p ressure attitude. Corresponding ozone measurement accuracies for indiv idual ozonesonde soundings were estimated to be about +/-6% near the g round, decrease to -7 to 17% in the high troposphere where ozone conce ntrations are low, increase to about +/-5% in the low stratosphere and remain so to an altitude of about 10 mbar (similar to 32 km), then de crease to -14 to 6% at 4 mbar (similar to 38 km) where ozone concentra tions are again low. Stratospheric ozone measurements were also made d uring STOIC with ground-based lidars and a microwave radiometer that w ill be used for ozone measurements in the future at sites of the Netwo rk for the Detection of Stratospheric Change(NDSC). The ECC ozonesonde observations provided useful comparison data for evaluating the perfo rmance of the lidar and microwave instruments.