Recorded presentation15A.1
Interactions between ozone and climate: 1960-2100
Steven Pawson, NASA/GSFC, Greenbelt, MD; and R. S. Stolarski, A. R. Douglass, J. Perlwitz, and J. E. Nielsen
Stratospheric ozone is a radiatively active gas with important contributions to climate forcing at both solar and infrared wavelengths. At the same time as greenhouse gas concentrations have increased, the ozone concentration has decreased because of the emission of precursor chemicals, largely CFCs. This has led to substantial changes in ozone over the past few decades. The first part of this presentation will examine how ozone and climate have interacted in the latter part of the 20th Century. The Goddard Earth Observing System Chemistry Climate Model (GEOS-CCM) is used for this study, in runs forced with observed sea-surface temperatures, sea-ice distributions, and greenhouse gas concentrations. To examine the impacts of ozone, runs with and without increases in chlorine-containing pollutants are compared: the focus will be on the signature of the stratospheric ozone depletion on the tropospheric circulation. The second part of the presentation will examine the impacts of ozone changes through the 21st Century, as GHGs continue to increase while ozone levels recover as the amount of chlorine in the stratosphere decreases. The focus will be on the time-dependent signals in the thermal structure of the upper troposphere, as well as large-scale patterns in the tropospheric circulation. Recorded presentation
Session 15A, Detection and attribution of climate change: Part IV
Thursday, 24 January 2008, 1:30 PM-3:00 PM, 215-216
Next paper