 |
| Titel |
Persistence of ozone anomalies in the Arctic stratospheric vortex in autumn |
| VerfasserIn |
D. Blessmann, I. Wohltmann, R. Lehmann, M. Rex |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 12, no. 11 ; Nr. 12, no. 11 (2012-06-01), S.4817-4823 |
| Datensatznummer |
250011212
|
| Publikation (Nr.) |
 copernicus.org/acp-12-4817-2012.pdf |
|
|
|
|
|
| Zusammenfassung |
| Dynamical processes during the formation phase of the Arctic stratospheric
vortex in autumn (from September to December) can introduce considerable
interannual variability in the amount of ozone that is incorporated into the
vortex. Chemistry in autumn tends to remove part of this variability because
ozone relaxes towards equilibrium. As a quantitative measure of how important
dynamical variability during vortex formation is for the winter ozone
abundances above the Arctic we analyze which fraction of an ozone anomaly
induced during vortex formation persists until early winter (3 January). The
work is based on the Lagrangian Chemistry Transport Model ATLAS. In a case
study, model runs for the winter 1999–2000 are used to assess the fate of an
ozone anomaly artificially introduced during the vortex formation phase on 16
September. In addition, runs with reduced resolution explore the sensitivity
of the results to interannual changes in transport, mixing, temperatures and
NOx. The runs provide information about the persistence of the
induced ozone anomaly as a function of time, potential temperature and
latitude. The induced ozone anomaly survives longer inside the polar vortex
than outside the vortex. Half of the initial perturbation survives until 3
January at 550 K inside the polar vortex, with a rapid fall off towards
higher levels, mainly due to NOx induced chemistry. Above 750 K
the signal falls to values below 0.5%. Hence, dynamically induced ozone
variability from the early vortex formation phase cannot significantly
contribute to early winter variability above 750 K. At lower levels
increasingly larger fractions of the initial perturbation survive, reaching
90% at 450 K. In this vertical range dynamical processes during the
vortex formation phase are crucial for the ozone abundance in early winter. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|