HR: 0800h
AN: A11B-0036    [Abstracts]
TI: Episodes of High Surface Ozone Amounts During the Summer at South Pole, Antarctica
AU: * Oltmans, S J
EM: samuel.j.oltmans@noaa.gov
AF: NOAA Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Bouder, CO 80305 United States
AU: Johnson, B J
EM: bryan.johnson@noaa.gov
AF: NOAA Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Bouder, CO 80305 United States
AU: Helmig, D
EM: detlev.helmig@colorado.edu
AF: Institute of Arctic and Alpine Research, University of Colorado, 1560 30th Street, Boulder, CO 80309 United States
AU: Oncley, S
EM: oncley@ucar.edu
AF: National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307 United States
AB: During the months of November, December and January episodes of enhanced ozone amounts greater than 35 ppb are seen in the surface ozone record at South Pole, Antarctica. Using the long-term surface and vertical profile measurements of ozone the character and frequency of these high ozone events are compared with the more quiescent periods. In order to better characterize the vertical structure of ozone in the lower layers, a procedure has been developed for correcting for the time response of the ozonesondes. This correction is based on a campaign in December 2003 in which slowly ascending ozonesondes on a tethered balloon were compared with the more rapidly ascending balloon release ozonesondes. At times of high ozone mixing ratio at the surface there is a strong gradient in the lowest 0.5 km layer with the largest ozone amounts near the surface. On the other hand when ozone near the surface is less than about 20-25 ppb, ozone is well mixed without a strong gradient. For intermediate conditions (ozone in the range 25-35 ppb) there is usually a gradient similar to that seen for the high ozone cases but with somewhat less vertical depth. Conditions of high or moderate surface ozone amounts dominate overall from mid November to mid January indicating that a surface source is active through much of this time.
DE: 0322 Constituent sources and sinks
DE: 0368 Troposphere--constituent transport and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting