HR: 1340h
AN: A23B-0948    [Abstracts]
TI: Stratosphere-Troposphere Exchange Trend From Changing Sea-Surface Temperatures
AU: * Olsen, M A
EM: olsen@code613-3.gsfc.nasa.gov
AF: Goddard Earth Systems and Technology Center University of Maryland, Baltimore County, NASA Goddard Space Flight Center Mailstop 613.3, Greenbelt, MD 20771 United States
AU: Douglass, A R
EM: Anne.R.Douglass@nasa.gov
AF: NASA, NASA Goddard Space Flight Center, Greenbelt, MD 20771 United States
AU: Stolarski, R S
EM: stolar@polska.gsfc.nasa.gov
AF: NASA, NASA Goddard Space Flight Center, Greenbelt, MD 20771 United States
AU: Schoeberl, M R
EM: Mark.R.Schoeberl@nasa.gov
AF: NASA, NASA Goddard Space Flight Center, Greenbelt, MD 20771 United States
AB: Two fifty-year integrations of a global circulation model have been performed. Interannually varying Hadley Centre sea-surface temperatures (SSTs) were used in one simulation; the other used annually repeating average SSTs. All other inputs to the simulation, including greenhouse gas concentrations were identical in the simulations. The extra-tropical stratosphere-troposphere exchange (STE) increased by 3% per decade in the northern hemisphere and 2% per decade in the southern hemisphere with interannually varying SSTs. This trend is comparable in magnitude and sign to that found in previous model studies that included increasing greenhouse gas concentrations. No significant trend was found with the annually repeating SSTs. The atmospheric wave-driving response to the SSTs will be discussed. We will demonstrate the sensitivity of the amplitudes of the seasonal cycle of HCl and O3 to the trend in the STE, and examine the data record for this signature of a trend in the STE. Such a change in STE, if real, has important consequences for evaluation of the past trends in stratospheric ozone and for ozone recovery.
DE: 0341 Middle atmosphere: constituent transport and chemistry (3334)
DE: 1610 Atmosphere (0315, 0325)
DE: 3334 Middle atmosphere dynamics (0341, 0342)
DE: 3362 Stratosphere/troposphere interactions
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005