ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-10-7697-2010 Options to accelerate ozone recovery: ozone and climate benefits Daniel J. S. 1 Fleming E. L. 2 3 Portmann R. W. 1 Velders G. J. M. 4 Jackman C. H. 2 Ravishankara A. R. 1 National Oceanic and Atmospheric Administration, Earth System Research Laboratory, Chemical Sciences Division, Boulder, CO 80305, USA NASA Goddard Space Flight Center, Greenbelt, Maryland, 20771, USA Science Systems and Applications, Inc., Lanham, MD 20706, USA Netherlands Environmental Assessment Agency, 3720 AH Bilthoven, The Netherlands 18 08 2010 10 16 7697 7707 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/10/7697/2010/acp-10-7697-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/7697/2010/acp-10-7697-2010.pdf

Hypothetical reductions in future emissions of ozone-depleting substances (ODSs) and N<sub>2</sub>O are evaluated in terms of effects on equivalent effective stratospheric chlorine (EESC), globally-averaged total column ozone, and radiative forcing through 2100. Due to the established success of the Montreal Protocol, these actions can have only a fraction of the impact on ozone depletion that regulations already in force have had. If all anthropogenic ODS and N<sub>2</sub>O emissions were halted beginning in 2011, ozone is calculated to be higher by about 1–2% during the period 2030–2100 compared to a case of no additional restrictions. Direct radiative forcing by 2100 would be about 0.23 W/m<sup>2</sup> lower from the elimination of anthropogenic N<sub>2</sub>O emissions and about 0.005 W/m<sup>2</sup> lower from the destruction of the chlorofluorocarbon (CFC) bank. Due to the potential impact of N<sub>2</sub>O on future ozone levels, we provide an approach to incorporate it into the EESC formulation, which is used extensively in ozone depletion analyses. The ability of EESC to describe total ozone changes arising from additional ODS and N<sub>2</sub>O controls is also quantified.

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