HR: 15:25h
AN: A33H-08    [Abstracts]
TI: HIRDLS Observations of Strat-Trop Exchange in Thin Laminae in the Sub-Tropical Jet Region
AU: * Gille, J
EM: gille@ucar.edu
AF: CLAS, University of Colorado, FL-0 3450 Mitchell Lane, Boulder, CO 80301, United States
AU: * Gille, J
EM: gille@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307,
AU: Yudin, V
EM: vyudin@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307,
AU: Nardi, B
EM: nardi@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307,
AU: Phillips, T
EM: phillitr@ucar.edu
AF: CLAS, University of Colorado, FL-0 3450 Mitchell Lane, Boulder, CO 80301, United States
AU: Barnett, J
EM: j.barnett1@physics.ox.ac.uk
AF: Department of Atmospheric, Oceanic & Planetary Physics Oxford University Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, United Kingdom
AU: Khosravi, R
EM: rashid@ucar.edu
AF: NCAR, P.O. Box 3000, Boulder, CO 80307,
AB: High Resolution Dynamics Limb Sounder (HIRDLS) data show atmospheric structures in the mid-latitude UT/LS region in which thin layers of low-latitude air having a low ozone mixing ratio move pole-ward over the subtropical jet stream during northern hemisphere winter, and simultaneously layers of mid-latitude air from the lowermost stratosphere, with higher ozone amounts move equator-ward beneath them. These layers appear to be too thin vertically to be seen by other instruments. The flows were observed between double tropopauses, at the time of a sudden stratospheric warming. This study extends the previous work to evaluate the frequency of such events as a function of time. Particular attention has been focused on the frequency, size, and effects of these structures at the end of the Northern Hemisphere winter, when more frequent tropopause fold events have been reported. Comparison to the overall dynamical situation shown by the GEOS-5 data reveals certain conditions in which these flows occur. The relationship of these structures to double tropopauses and the sub-tropical jet will be shown.
DE: 0341 Middle atmosphere: constituent transport and chemistry (3334)
DE: 0365 Troposphere: composition and chemistry
DE: 3360 Remote sensing
DE: 3362 Stratosphere/troposphere interactions
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting