Emission location dependent ozone depletion potentials for very short-lived halogenated species

I. Pisso, P. H. Haynes, K. S. Law
2010 Atmospheric Chemistry and Physics Discussions  
We present trajectory-based estimates of Ozone Depletion Potentials (ODPs) for very short-lived halogenated source gases as a function of surface emission location. The ODPs are determined by the fraction of source gas and its degradation products which reach the stratosphere, depending primarily on tropospheric transport and chemistry, 5 and the effect of the resulting reactive halogen in the stratosphere, which is determined by stratospheric transport and chemistry, in particular by
more » ... icular by stratospheric residence time. Reflecting the different timescales and physico-chemical processes in the troposphere and stratosphere, the estimates are based on calculation of separate ensembles of trajectories for the troposphere and stratosphere. A methodology is described by which 10 20 These first estimates, which include some simplifying assumptions, show larger ODP values than previous studies, particularly over Southern Asia, suggesting that emissions of short-lived halogen source gases in certain geographical regions could have a significant impact on stratospheric ozone depletion. 16278 species would destroy ozone even more effectively but are considered to be less important given current knowledge of emissions and hence of likely stratospheric iodine loading. Calculating ODPs for VSLS is challenging because the ODPs are expected to be strong functions of location and time of emission, implying the need for many calculations with different emission distributions. Ultimately, multiple calculations are needed with global 3-D models that represent both the tropospheric chemistry and transport processes
doi:10.5194/acpd-10-16277-2010 fatcat:ejcesjysofhklinu2o3tusuuse