HR: 0830h
AN: A41C-0706    [PDF]
TI: Comparing Model Ozone Loss During the SOLVE and SOLVE-2 Winters
AU: * Drdla, K
EM: Katja.Drdla@nasa.gov
AF: NASA Ames Research Center, Mailstop 245-4, Moffett Field, CA 94035 United States
AB: Model simulations have been used to analyze the factors influencing Arctic ozone loss during the 1999-2000 winter and 2002-2003 winters, i.e., the winters examined by the SAGE III Ozone Loss and Validation Experiment (SOLVE) and SOLVE-2 campaigns. For both winters, the evolution of the Arctic vortex from November to April has been simulated using a trajectory-based microphysical and photochemical model. Extensive PSC formation and strong ozone depletion are evident in both winters. However, the ozone loss begins earlier in the 2002-2003 winter, with significant ozone depletion by early January. Analysis of the model results shows that during December 2002 not only cold temperatures but also the vortex structure was critical, allowing PSC-processed air parcels to experience significant solar exposure. The resultant ozone loss can be differentiated from ozone loss that occurs in the springtime, in particular because of the continued exposure to PSCs. For example, chlorine reactivation by the PSCs causes ozone loss to be insensitive to denitrification. Therefore, diagnosing the extent of ozone loss early in the winter is critical in understanding the overall winter-long ozone depletion.
DE: 0317 Chemical kinetic and photochemical properties
DE: 0320 Cloud physics and chemistry
DE: 0340 Middle atmosphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting