Articles | Volume 24, issue 22
https://doi.org/10.5194/acp-24-13081-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-24-13081-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Nov 2024
Research article |
| 27 Nov 2024
| 27 Nov 2024
The return to 1980 stratospheric halogen levels: a moving target in ozone assessments from 2006 to 2022
Megan J. Lickley
CORRESPONDING AUTHOR
The Earth Commons, Georgetown University, Washington, DC 20057, USA
Science, Technology, and International Affairs, Georgetown University, Washington, DC 20057, USA
John S. Daniel
NOAA Chemical Sciences Laboratory, Boulder, CO 80305, USA
Laura A. McBride
Department of Chemistry and Biochemistry, Albright College, Reading, PA 19612, USA
now at: Science and Technology Corporation, Columbia, MD 21046, USA
Ross J. Salawitch
Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20740, USA
Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD 20740, USA
Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20740, USA
Guus J. M. Velders
National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands
Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, the Netherlands
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Short summary
The expected ozone recovery date was delayed by 17 years between the 2006 and 2022 international scientific assessments of ozone depletion. We quantify the primary drivers of this delay. Changes in the metric used to estimate ozone recovery explain ca. 5 years of this delay. Of the remaining 12 years, changes in estimated banks, atmospheric lifetimes, and emission projections explain 4, 3.5, and 3 years of this delay, respectively.
The expected ozone recovery date was delayed by 17 years between the 2006 and 2022 international...
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