Journal Article

PreJuSER-18311

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Stratospheric ozone chemistry in the Antarctic:What controls the lowst values that can be reached and their recovery?

Grooß, J.-U.FZJ* ; Brautzsch, K.FZJ* ; Pommrich, R. ; Solomon, S. ; Müller, R.FZJ*

2011
EGU Katlenburg-Lindau

This record in other databases:  

Please use a persistent id in citations: http://hdl.handle.net/2128/9950  doi:10.5194/acp-11-12217-2011

Abstract: Balloon-borne observations of ozone from the South Pole Station have been reported to reach ozone mixing ratios below the detection limit of about 10 ppbv at the 70 hPa level by late September. After reaching a minimum, ozone mixing ratios increase to above 1 ppmv on the 70 hPa level by late December. While the basic mechanisms causing the ozone hole have been known for more than 20 yr, the detailed chemical processes determining how low the local concentration can fall, and how it recovers from the minimum have not been explored so far. Both of these aspects are investigated here by analysing results from the Chemical Lagrangian Model of the Stratosphere (CLaMS). As ozone falls below about 0.5 ppmv, a balance is maintained by gas phase production of both HCl and HOCl followed by heterogeneous reaction between these two compounds in these simulations. Thereafter, a very rapid, irreversible chlorine deactivation into HCl can occur, either when ozone drops to values low enough for gas phase HCl production to exceed chlorine activation processes or when temperatures increase above the polar stratospheric cloud (PSC) threshold. As a consequence, the timing and mixing ratio of the minimum ozone depends sensitively on model parameters, including the ozone initialisation. The subsequent ozone increase between October and December is linked mainly to photochemical ozone production, caused by oxygen photolysis and by the oxidation of carbon monoxide and methane.

Keyword(s): J

Note: We thank Herman Smit and Peter von der Gathen for helpful discussions on the detection limits of ozone sondes. This work was supported by the RECONCILE project of the European Commission Seventh Framework Programme (FP7) under the Grant number RECONCILE-226365-FP7-ENV-2008-1.

---

Contributing Institute(s):

1. Stratosphäre (IEK-7)

Research Program(s):

1. Atmosphäre und Klima (P23)
2. RECONCILE - Reconciliation of essential process parameters for an enhanced predictability of arctic stratospheric ozone loss and its climate interactions. (226365) (226365)

Appears in the scientific report 2011

---

Database coverage:
;

---