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| Titel |
Multi-model assessment of stratospheric ozone return dates and ozone recovery in CCMVal-2 models |
| VerfasserIn |
V. Eyring, I. Cionni, G. E. Bodeker, A. J. Charlton-Perez, D. E. Kinnison, J. F. Scinocca, D. W. Waugh, H. Akiyoshi, S. Bekki, M. P. Chipperfield, M. Dameris, S. Dhomse, S. M. Frith, H. Garny, A. Gettelman, A. Kubin, U. Langematz, E. Mancini, M. Marchand, T. Nakamura, L. D. Oman, S. Pawson, G. Pitari, D. A. Plummer, E. Rozanov, T. G. Shepherd, K. Shibata, W. Tian, P. Braesicke, S. C. Hardiman, J. F. Lamarque, O. Morgenstern, J. A. Pyle, D. Smale, Y. Yamashita |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 10, no. 19 ; Nr. 10, no. 19 (2010-10-07), S.9451-9472 |
| Datensatznummer |
250008812
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| Publikation (Nr.) |
 copernicus.org/acp-10-9451-2010.pdf |
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| Zusammenfassung |
| Projections of stratospheric ozone from a suite of chemistry-climate models
(CCMs) have been analyzed. In addition to a reference simulation where
anthropogenic halogenated ozone depleting substances (ODSs) and greenhouse
gases (GHGs) vary with time, sensitivity simulations with either ODS or GHG
concentrations fixed at 1960 levels were performed to disaggregate the
drivers of projected ozone changes. These simulations were also used to
assess the two distinct milestones of ozone returning to historical values
(ozone return dates) and ozone no longer being influenced by ODSs (full
ozone recovery). The date of ozone returning to historical values does not
indicate complete recovery from ODSs in most cases, because GHG-induced
changes accelerate or decelerate ozone changes in many regions. In the upper
stratosphere where CO2-induced stratospheric cooling increases ozone,
full ozone recovery is projected to not likely have occurred by 2100 even
though ozone returns to its 1980 or even 1960 levels well before (~2025 and 2040, respectively). In contrast, in the tropical lower
stratosphere ozone decreases continuously from 1960 to 2100 due to projected
increases in tropical upwelling, while by around 2040 it is already very
likely that full recovery from the effects of ODSs has occurred, although
ODS concentrations are still elevated by this date. In the midlatitude lower
stratosphere the evolution differs from that in the tropics, and rather than
a steady decrease in ozone, first a decrease in ozone is simulated from 1960
to 2000, which is then followed by a steady increase through the 21st
century. Ozone in the midlatitude lower stratosphere returns to 1980 levels
by ~2045 in the Northern Hemisphere (NH) and by ~2055 in the
Southern Hemisphere (SH), and full ozone recovery is likely reached by 2100
in both hemispheres. Overall, in all regions except the tropical lower
stratosphere, full ozone recovery from ODSs occurs significantly later than
the return of total column ozone to its 1980 level. The latest return of
total column ozone is projected to occur over Antarctica (~2045–2060)
whereas it is not likely that full ozone recovery is reached by the end of
the 21st century in this region. Arctic total column ozone is projected
to return to 1980 levels well before polar stratospheric halogen loading
does so (~2025–2030 for total column ozone, cf. 2050–2070 for
Cly+60×Bry) and it is likely that full recovery of total
column ozone from the effects of ODSs has occurred by ~2035. In
contrast to the Antarctic, by 2100 Arctic total column ozone is projected to
be above 1960 levels, but not in the fixed GHG simulation, indicating that
climate change plays a significant role. |
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