Estimation of Arctic polar vortex ozone loss during the winter of 1999-2000 using vortex-averaged airborne differential absorption lidar ozone measurements referenced to N2O isopleths - art. no. 4309

摘要

The NASA Langley UV differential absorption lidar (DIAL) system flew on the NASA DC-8 aircraft during the Stratospheric Aerosol and Gas Experiment (SAGE) III Ozone Loss and Validation Experiment/Third European Stratospheric Experiment on Ozone 2000 (SOLVE/THESEO 2000) mission from 30 November 1999 to 15 March 2000. The UV DIAL system measured ozone (O-3) profiles at altitudes from about 1 km above the aircraft up to about 26 km with a vertical resolution of 750 m and a horizontal resolution of 70 km below 19 km and 140 km above 19 km. In comparison with electrochemical concentration cell ozonesonde profiles, the UV DIAL O-3 measurements agreed to within 5% up to 20 km and 10% from 20 to 25 km. Ozone loss during the season was determined using the UV DIAL O-3 data along with air mass subsidence determined using N2O as a conservative tracer at five levels from 50 to 250 ppbv [Greenblatt et al., 2002]. O-3 mixing ratios were determined inside the polar vortex, away from the collar region along these five levels during the mission. The maximum O-3 loss determined from 30 November to 12 March was 1.55+/-0. 3 ppmv at the 440-450 K potential temperature (Theta) level, while the loss there between 20 January and 15 March was 1.3+/-0.3 ppmv. These results are comparable to many of the other reported losses for these periods, but lower than several. Some of the determinations of higher losses used a different method to determine descent during the season. These results indicate that a series of vertical profiles of O-3 that sample much of the vortex during the winter, along with determinations of the descent of air masses inside the vortex, can give a reasonable estimate of the O-3 changes during the season. [References: 41]